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Corydoras bethanae, new species (Figs. 1, 2A, 3A, 4-6, Table 1) Corydoras sp. CW006:��� Alexandrou et al., 2011: 85���86 (��� C. sp. CW6���; phylogeny; as member of the lineage 8; mimicry).��� Tencatt et al., 2019: 459���460 (comparison with C. arcuatus; photo in life (fig. 8) of the specimen designated as holotype herein). Holotype. MUSM 69403, female, 51.2 mm SL, Peru, Department of Loreto, Requena Province, Soplin District, r��o Blanco (close to the confluence with the r��o Tapiche), aquarium specimen imported in 2017 by Aquarium Glaser GmbH, Germany. Paratypes. BMNH 2017.5.25.1-21, 21, 43.7���57.3 mm SL, same data as holotype; BMNH 2018.7.5.4-5, 2, 56.0���56.0 mm SL; MNRJ 52311, 1, 53.1 mm SL; ZUFMS 6470, 1 of 3, 49.9 mm SL, 2 CS of 3, 55.0��� 56.9 mm SL, Peru, Department of Loreto, said to be from the r��o Ucayali basin, aquarium specimens imported in 2018 by Maidenhead Aquatics, Wigan, UK. Diagnosis. Corydoras bethanae can be distinguished from its congeners, except for those belonging to the lineage 8 sensu Alexandrou et al. (2011), by having the posterior margin of dorsal-fin spine with laminar serrations directed towards the origin of the spine (vs. absence of such serration pattern); from the species within lineage 8, except for C. arcuatus, it differs by the presence of a long, wide, arched, and continuous black stripe, which runs parallel to the dorsal profile of the body, extending at least from the region below anterior origin of dorsal fin to the anterior half of the ventral caudal-fin lobe (Fig. 2A) (vs. absence of a similar stripe in remaining lineage 8 congeners); from C. arcuatus (Fig. 2B) differs by the color pattern of the head (presence of a black stripe transversally crossing the eye, forming the typical mask-like blotch; mask clearly not fused to arched stripe in most specimens; some specimens with mask separated from arched stripe by a thin line around the suture between neurocranium (on the region composed by the posteroventral margin of parieto-supraoccipital plus the posterodorsal margin of the compound pterotic) and first dorsolateral body plate in C. bethanae (Figs. 3A and 6) vs. mask-like blotch absent; continuous black stripe extending from area at corner of mouth to anteroventral margin of orbit and starting again from posterodorsal margin of orbit; running close and in parallel to dorsum from this point to anterior margin of first dorsolateral body plate, merging with trunk section of the arched stripe in C. arcuatus (Fig. 3B), by having a longer snout (53.4���67.4% of HL vs. 42.1���51.5), a smaller HL (30.4���34.7% of SL vs. 41.1���51.4), and a larger least interorbital distance (42.6���49.2% of HL vs. 28.7���36.0). Additionally, the new species differs from C. gracilis Nijssen & Isbr ��cker, 1976 and C. narcissus Nijssen & Isbr ��cker, 1980a by having laminar serrations on posterior margin of pectoral-fin spine (vs. conical); from C. gracilis and C. urucu Britto, Wosiacki & Montag, 2009 by having pointed snout, presenting a long mesethmoid, with anterior tip larger than 50% of the entire length of the bone (vs. rounded snout, presenting a short mesethmoid, with anterior tip smaller than 50% of the entire bone length); from C. granti Tencatt, Lima & Britto, 2019 (Fig. 2C) by having ventral surface of trunk covered by small, non-coalescent platelets (vs. ventral surface of trunk entirely or partially covered by relatively large and coalescent platelets). Description. Morphometric data are presented in Table 1. Head laterally compressed with convex dorsal profile, roughly triangular in dorsal view. Snout conical in dorsal view, ranging from pointed to conspicuously pointed. Head profile in lateral view slightly concave from tip of snout to anterior nares, ascending slightly concave from this point to anterior portion of parieto-supraoccipital process; slightly convex or nearly straight from this point to dorsal-fin origin. Profile slightly convex along dorsal-fin base. Postdorsal-fin body profile slightly concave to adiposefin spine, concave from this point to caudal-fin base. Ventral profile of body nearly straight or slightly convex from isthmus to pectoral girdle, and slightly convex from this point until pelvic girdle. Profile nearly straight or slightly convex from pelvic girdle to base of first anal-fin ray, ascending abruptly concave until caudal-fin base. Body roughly elliptical in cross section at pectoral girdle, gradually becoming more compressed toward caudal fin. Eye rounded, located dorsolaterally on head. Orbit delimited anteriorly by lateral ethmoid, anterodorsally by frontal, posterodorsally by sphenotic, posteriorly by infraorbital 2, and ventrally by infraorbital 1. Anterior and posterior nares close to each other, only separated by flap of skin. Anterior naris tubular. Posterior naris close to anterodorsal margin of orbit, separated from it by distance slightly larger than naris diameter. Mouth small, subterminal, width slightly smaller than bony orbit diameter. Maxillary barbel long in size, reaching anteroventral limit of gill opening. Outer mental barbel slightly longer than maxillary barbel. Inner mental barbel fleshy, base of each counterpart slightly separated from each other. Small rounded papillae covering entire surface of all barbels, upper and lower lips, snout and isthmus. Mesethmoid long with anterior tip well developed, larger than 50% of bone length (see Britto, 2003: 123, character 1, state 0; fig. 1A); posterior portion relatively narrow, entirely covered by thin layer of skin. Middle portion of mesethmoid with strongly well-developed lateroventral process; region of process with width clearly larger than width of posterior portion of mesethmoid. Nasal capsule delimited anteriorly and ventrally by lateral ethmoid, and posteriorly and dorsally by frontal. Nasal slender, laterally curved, inner margin laminar; mesial border contacting only frontal. Lateral ethmoid conspicuously expanded anteriorly, with anterodorsal expansion contacting frontal and mesethmoid, and anteroventral expansion connected to lateroventral process of mesethmoid. Frontal elongated, ranging from narrow, width less than half of entire length, to relatively wide, with width equal to half of entire length; anterior projection long, size equal to or slightly larger than nasal length. Frontal fontanel large, slender, and somewhat ellipsoid; posterior tip extension entering anterior margin of parieto-supraoccipital. Sphenotic somewhat trapezoid, contacting parieto-supraoccipital dorsally, compound pterotic posteriorly, second infraorbital ventrally and frontal anteriorly (Fig. 4). Compound pterotic roughly pipe-shaped, with posteriormost portion contacting first lateral-line ossicle, posteroventral margin contacting cleithrum, and anteroventral margin contacting opercle and infraorbital 2, and posterior expansion almost entirely covering lateral opening of swimbladder capsule, leaving slender area on its dorsal margin covered only by thick layer of skin (Fig. 4). Parieto-supraoccipital wide, posterior process long and contacting nuchal plate; region of contact between posterior process and nuchal plate covered by thick layer of skin. Two laminar infraorbitals with minute odontodes. Infraorbital 1 large, ventral laminar expansion moderately developed, anterior portion with well-developed laminar expansion, reaching to or slightly surpassing anterior margin of nasal capsule; inner laminar expansion strongly reduced (Fig. 4). Infraorbital 2 small, widened, with posterior laminar expansion well developed; posteroventral margin contacting posterodorsal ridge of hyomandibula, posterodorsal edge contacting sphenotic and compound pterotic; inner laminar expansion strongly reduced (Fig. 4). Posterodorsal ridge of hyomandibula close to its articulation with opercle relatively slender, exposed, and bearing small odontodes. Dorsal ridge of hyomandibula between compound pterotic and opercle covered by thick layer of skin; covered by posterodorsal edge of infraorbital 2 in some specimens. Interopercle partially exposed, with anterior portion covered by thick skin layer; subtriangular, anterior projection well-developed. Preopercle elongated, ranging from relatively slender to widened; minute odontodes sparse on external surface. Opercle dorsoventrally elongated, width smaller than half of entire length; free margin slightly convex, without serrations and covered by small odontodes. Four branchiostegal rays decreasing in size posteriorly. Hypobranchial 2 somewhat triangular, tip ossified and directed towards anterior portion, posterior margin cartilaginous; ossified portion conspicuously well developed, its size about three times cartilaginous portion. Five ceratobranchials with expansions increasing posteriorly; ceratobranchial 1 with small process on anterior margin of mesial portion; ceratobranchial 3 with continuous laminar expansion on postero-lateral margin; ceratobranchial 5 toothed on posterodorsal surface, with 34 to 42 (2) teeth aligned in one row. Four epibranchials with similar size; epibranchial 2 slightly larger than others, with small pointed process on laminar expansion of posterior margin; epibranchial 3 with roughly triangular or somewhat trapezoid uncinate process on laminar expansion of posterior margin; uncinate process curved mesially in left side of paratype ZUFMS 6470, 56.9 mm SL. Two wide pharyngobranchials (3 and 4); pharyngobranchial 3 with roughly triangular laminar expansion on posterior margin; variably notched expansion in some specimens. Upper tooth plate oval, 34 to 47 (2) teeth aligned in two rows on posteroventral surface. Lateral-line canal reaching cephalic laterosensory system through compound pterotic, branching twice before reaching sphenotic: pterotic branch, with single pore, preoperculomandibular branch conspicuously reduced, with single pore opening at postotic main canal; postotic main canal becoming widened just posterior to pterotic branch. Sensory canal continuing through compound pterotic, reaching sphenotic as temporal canal, which splits into two branches: one branch giving rise to infraorbital canal, other branch connecting to frontal through supraorbital canal, both with single pore. Supraorbital canal branched, running through nasal bone. Epiphyseal branch conspicuously reduced; pore opening close to supraorbital main canal, directed towards frontal fontanel. Nasal canal with two or three openings, first on posterior edge, second, when present, on posterolateral portion and generally fused with first pore, and third on anterior edge. Infraorbital canal running through entire infraorbital 2, extending to infraorbital 1 and opening into two pores. Preoperculomandibular branch giving rise to preoperculo-mandibular canal, which runs through entire preopercle with three openings, leading to pores 3, 4, and 5, respectively. Dorsal fin subtriangular, located just posterior to second or third dorsolateral body plate. Dorsal-fin rays II,7 (1), II,8* (19), I,9 (4), posterior margin of dorsal-fin spine with 18 to 19 poorly to moderately-developed laminar serrations; most serrations directed towards origin of spine; some serrations variably perpendicularly directed; serrations absent close to origin of spine; small odontodes on anterior and lateral surfaces of spine (Fig. 5A). Nuchal plate well developed, almost entirely exposed, with minute odontodes. Spinelet short, spine moderately developed, adpressed distal tip slightly surpassing posterior origin of dorsal-fin base, and anterior margin with small odontodes. Pectoral fin roughly triangular, its origin just posterior to gill opening. Pectoral-fin rays I,6*(1), I,7 (2), I,8 (4), I,9 (15), I,9,i (1), posterior margin of pectoral spine with 24 to 28 poorly- to moderately-developed laminar serrations along almost its entire length, absent close to origin of spine; most serrations directed towards pectoral-fin origin; some serrations perpendicularly directed or directed towards tip of spine; small odontodes on anterior, dorsal and ventral surfaces of spine (Fig. 5B). Anteroventral portion of cleithrum exposed; posterolateral portion of scapulocoracoid moderately developed, exposed, with anterior portion strongly expanded anteriorly, almost reaching to or contacting anteroventral portion of cleithrum; exposed areas bearing small odontodes; Opening of axillary gland sensu Kiehl et al. (2006) located just posterior to pectoral-fin spine base. Pelvic fin oblong, located just below first ventrolateral body plate, and at vertical through region between first and second branched dorsal-fin ray. Pelvic-fin rays i,5* (24). Adipose fin roughly triangular, separated from base of last dorsal-fin ray by generally six dorsolateral body plates. Anal fin subtriangular, located just posterior to 12 th or 13 th ventrolateral body plates, and at vertical through adiposefin spine base. Anal-fin rays ii,6* (22). Caudal fin bilobed, with dorsal lobe slightly larger than ventral lobe; lobes with similar size in some specimens. Caudal-fin rays i,10,i (1), i,11,i (2), i,12,i* (20), i,13,i (1), generally five or six dorsal and ventral procurrent rays. Three laterosensory canals on trunk. First ossicle tubular, second ossicle laminar, and third lateral-line canal encased in third dorsolateral body plate. Body plates with minute odontodes scattered over exposed area, conspicuous line of odontodes confined on posterior margins. Dorsolateral body plates 24* (22), 25 (2). Ventrolateral body plates 21 (10), 22* (13), 23 (1). Dorsolateral body plates along dorsal-fin base 6 (2), 7* (22). Dorsolateral body plates between adipose- and caudal-fin 7 (3), 8* (18), 9 (1). Preadipose platelets 4* (3). Small platelets covering base of caudal-fin rays. Small platelets disposed dorsally and ventrally between junctions of lateral plates on posterior portion of caudal peduncle. Anterior margin of orbit, above posterior portion of lateral ethmoid, variably with small, irregular platelets bearing odontodes. Ventral surface of trunk densely covered by small irregular platelets bearing odontodes. Vertebral count 22 (2). Ribs 7 (1), 8 (1); first pair conspicuously large, its middle portion closely connected to first ventrolateral body plate; its tip connected to anterior external process of basipterygium. Complex vertebra moderately developed. Color in alcohol. Overall color light whitish, grey, light beige, or tan, with area above dark arched line and mask being slightly darker, sometimes orange-brown; melanophores along, above and below the midline of the lateral scutes, being darker and larger in some specimens; snout area anterior to dark eye mask and opercular region dark grey or diffuse black. Eye mask and body stripe (as set out in diagnosis) black; basal portion of six outermost segmented rays of ventral lobe of caudal fin black, and innermost procurrent ray of same lobe black or dark grey, forming extension of body stripe; some specimens with one dark or black pigmented transverse, diffuse, vertical band in caudal fin. Pale area on middle portion of dorsolateral surface of cleithrum corresponds with axillary gland sensu Kiehl et al. (2006) underneath; holotype similarly colored area on the ventral margin of the base of the adipose-fin spine. Color in life. See Figs 2A, and 6 of the holotype and two paratypes, respectively, whilst alive for color in life. Overall color same as in alcohol; third dorsolateral body scute usually whitish; green or gold to copper hue on lateral scutes above and below midline, opercular area, cleithrum, and underneath and behind the eye; snout area anterior to dark eye mask is usually light grey. Eye mask, body, and caudal fins dark markings as per preserved specimens. Whitish narrow transversal area from ventral half of fourth dorsolateral body plate, passing through dorsal half of first ventrolateral body plate, and reaching to posterolateral margin of cleithrum. Other fin membranes and rays hyaline, with some of the dorsal and adipose fin membranes with whitish chromatophores (colors in Fig. 6 are background colors). Color of fry can be determined from the spawning in the account by Petersson (2020). Sexual dimorphism. In addition to a tubular genital papilla (see Spadella et al., 2017), males have more pointed and elongated pelvic fins; the dark arched body stripe can appear proportionately wider; and tend to have the lateral scutes with darker and larger markings along, above and below the midline of flank. Geographical distribution. Corydoras bethanae is so far only known from the r��o Blanco system (r��o Ucayali basin), Soplin District, Requena Province, Department of Loreto, Peru (Fig. 7). Based on the findings of Corahua et al. (2015) it is likely that it is found in the streams that drain into the main river. Natural history notes. Corydoras bethanae may be found in blackwater streams that drain into the predominantly whitewater r��o Blanco (Fig. 8A), although the UK aquarist Mark Breeze (pers. comm.) states that in the dry season he found small clearwater tributary streams near the confluence with the r��o Tapiche (Fig. 8B). Those streams had a sand substrate with hardly any leaf litter and just overhanging terrestrial plants. Corahua et al. (2015) found several Corydoras species in shallow, lotic blackwater streams or flooded forests that flowed into the middle reaches of the r��o Blanco, that were low in pH (5.4���5.5), electrical conductivity (4.8���8.9 ��s/cm), temperature of 25 degrees Centigrade, with abundant organic detritus, and white sand. A site in the lower region, closer to the type locality of Corydoras bethanae, was the same except it was lentic, the pH ranged from 4.1 ��� 5.6, and the electrical conductivity was 29.5���41.0 ��s/cm. Corydoras granti was found by Corhua et al. (2015) in this location (misidentified as Corydoras arcuatus); another species with an arched dark body band. Corahua et al. (2015) list at least eight species from the r��o Blanco, and in addition to those, information from fish collectors indicates that the following Corydoras can also be found in the r��o Blanco system: Corydoras coriatae Burgess, 1997, C138 (which is superficially similar to Corydoras bethanae), and CW073. Grant (2020) discussed curious behavior exhibited by Corydoras bethanae when in the aquarium. All corydoradins appear to be able to maintain their position in the water column, above the substrate, by using a combination of body movement and fin movement. They usually to do this when maneuvering while performing definite activities e.g., avoiding another fish or predator, feeding, spawning etc. In the aquarium C. bethanae tend to hover regularly and for long periods of time, apparently not related to any particular activity; a behavior that has not been reported for other lineage 8 Corydoras. The pale transversal bar from fourth dorsolateral body plate to posterolateral margin of cleithrum corresponds with a large ligament attached dorsally to the transverse process of dorsal pterygiophore and ventrally to the posterior laminar expansion of the first rib, which itself is connected to the anterior external process of basipterygium. Such condition may have some effect on the ability, Published as part of Bentley, Rebecca Frances, Grant, Steven & Tencatt, Luiz Fernando Caserta, 2021, A new arc-striped species of Corydoras Lac��p��de, 1803 (Teleostei: Callichthyidae) from the Peruvian Amazon, pp. 184-200 in Zootaxa 4948 (2) on pages 185-196, DOI: 10.11646/zootaxa.4948.2.2, http://zenodo.org/record/4620756, {"references":["Alexandrou, M. A., Oliveira, C., Maillard, M., McGill, R. A. R., Newton, J., Creer, S. & Taylor, M. I. (2011) Competition and phylogeny determine community structure in M ʾ llerian co-mimics. Nature, 469, 84 - 89. https: // doi. org / 10.1038 / nature 09660","Tencatt, L. F. C., Lima, F. C. T. & Britto, M. R. (2019) Deconstructing an octongeneric misconception reveals the true Corydoras arcuatus Elwin 1938 (Siluriformes: Callichthyidae) and a new Corydoras species from the Amazon basin. Journal of Fish Biology, 95 (2), 453 - 471. https: // doi. org / 10.1111 / jfb. 13980","Britto, M. R., Wosiacki, W. B. & Montag, L. F. A. (2009) A new species of Corydoradinae catfish (Ostariophysi: Siluriformes: Callichthyidae) from Rio Solimies Basin, Brazil. Copeia, 4, 684 - 689. https: // doi. org / 10.1643 / CI- 08 - 228","Kiehl, E., Rieger, C. & Greven, H. (2006) Axillary gland secretions contribute to the stress-induced discharge of a bactericidal substance in Corydoras sterbai (Callichthyidae, Siluriformes). Verhandlungen der Gesellschaft f ʾ r Ichthyologie, 6, 111 - 115.","Petersson, M. (2020) Breeding Corydoras CW 006 (Callichthyidae). Journal of the Catfish Study Group, 21 (4), 6 - 7.","Spadella, M. A., Desan, S. P., Henriques, T. C. B. P. O. & Oliveira, C. (2017) Variation in male reproductive system characters in Corydoradinae (Loricarioidei: Callichthyidae) reflects the occurrence of different lineages in this subfamily. Neotropical Ichthyology, 15, e 160039. https: // doi. org / 10.1590 / 1982 - 0224 - 20160039","Corahua, I., Aldea-Guevara, M. I. & Hidalgo, M. H. (2015) Peces / Fish. In: Pitman, N., Vriesendorp, C., Rivera Chavez, L., Wachter, T., Alvira Reyes, D., del Campo, A., Gagliardi-Urrutia, G., Rivera Gonzalez, D., Trevejo, L., Rivera Gonzalez, D. & Heilpern, S. (Eds.), Peru: Tapiche-Blanco. Rapid Biological and Social Inventories Report 27. Field Museum, Chicago, pp. 109 - 117 + 290 - 297 + 420 - 435.","Burgess, W. E. (1997) Corydoras coriatae, a new species of callichthyid catfish related to Corydoras fowleri. Tropical Fish Hobbyist, 45, 138 - 147.","Grant, S. (2020) Hovering behaviour in Corydoras CW 006. Journal of the Catfish Study Group, 21 (1), 27 - 29."]}

Hypostomus froehlichi, new species (Figs. 1–4 and 6, Table 1 and 2) Holotype. NUP 22689, 226.2 mm SL, Bodoquena, Mato Grosso do Sul State, Brazil, córrego Salobrinha, tributary of rio Miranda, rio Paraguay basin, -20.68273, -56.78600, Mar 2007, O. Froehlich et al. Paratypes. All from Brazil, Mato Grosso do Sul State, Bodoquena, rio Paraguay basin, córrego Salobrinha, except when indicated: LIRP 5226, 5, 115.8 – 128.6 mm SL, Bonito, rio Formoso, -21.07916, -56.33916, 29 Aug 2004, H. F. dos Santos, O. Froehlich & R. Castro. LIRP 5228, 3, 163.1 – 222.2 mm SL, rio Salobra, -20.53860, -56.71500, 2 Sep 2004, H. F. dos Santos, O. Froehlich & R. Castro. LIRP 5240, 39, 25.6 –209.0 mm SL, rio Salobra, -20.53860, -56.71500, 22 Aug 2004, H. F. dos Santos, O. Froehlich & R. Castro. LIRP 5242, 2, 231.2 – 232.5 mm SL, rio Salobra -20.73805, -56.73472, 22 Aug 2004, H. F. dos Santos, O. Froehlich & R. Castro. NUP 5077, 5, 52.2–201.1 mm SL, rio Salobra, -20.49555, -56.86333, 27 Dec 2006, A. G. Bifi. NUP 12138, 2, 235.3 – 239.1 mm SL, rio Salobra, -20.78027, -56.74194, Dec 2005, O. Froehlich et al. NUP 12139, 2, 223.0– 227.8 mm SL, rio Salobra, -20.78027, -56.74194, Dec 2005, O. Froehlich et al. NUP 12140, 2, 235.3 – 241.8 mm SL, rio Salobra, -20.78027, -56.74194, Dec 2005, O. Froehlich et al. NUP 12141, 1, 225.0 mm SL, rio Salobra, -20.78027, -56.74194, Dec 2005, O. Froehlich et al. ZUFMS 904, 18, 20.5–78.2 mm SL, rio Salobra, -20.67527, -56.75694, 13 May 2001, O. Froehlich, M. R. Cavallaro & J. Sedenho. ZUFMS 1024, 14, 25.5 –74.0 mm SL, rio Salobra, -20.67527, -56.75694, 28 Jun 2001, O. Froehlich. ZUFMS 1085, 2, 51.6–66.5 mm SL, rio Salobra, -20.67527, -56.75694, 10 Oct 2001, O. Froehlich, E. Amorim, M. V. Costa & L. P. C. Lopes. ZUFMS 1126, 127, 21.2 –122.0 mm SL, rio Salobra, -20.67527, -56.75694, 13 Oct 2001, O. Froehlich, M. V. Costa & L. P. C. Lopes. ZUFMS 1171, 6, 11.5–61.7 mm SL, rio Salobra, -20.67527, -56.75694, 10 Sep 2001, O. Froehlich, M. R. Cavallaro, F. M. Fernandes, L. N. Carvalho & L. S. Inocêncio. ZUFMS 1175, 89, 18.7–56.4 mm SL, rio Salobra, -20.67527, -56.75694, 21 May 2000, O. Froehlich, M. R. Cavallaro, R. S. Arruda, D. Silva & L. S. Inocêncio. ZUFMS 1179, 83, 16.1–65.2 mm SL, rio Salobra, -20.67527, -56.75694, 14 May 2001, L.S. Inocêncio, M. R. Cavallaro, O. Froehlich & J. Sedenho. ZUFMS 1183, 1, 40.4 mm SL, rio Salobra, -20.67527, -56.75694, 21 May 2000, O. Froehlich. ZUFMS 1186, 3, 10.6–15.1 mm SL, rio Salobra, -20.67527, -56.75694, 8 Jun 2000, O. Froehlich. ZUFMS 1190, 1, 35.3 mm SL, rio Salobra, -20.67527, -56.75694, 20 May 2000, O. Froehlich. ZUFMS 1545, 34, 28.5–65.8 mm SL, rio Salobra, -20.67527, -56.75694, 10 Sep 2000, O. Froehlich. ZUFMS 2525, 41, 12.8–50.6 mm SL, rio Salobra, -20.78166, -56.74194, 3 Sep 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 2590, 9, 33.3–46.5 mm SL, rio Salobra, -20.67, -56.76055, 30 Aug 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 4470, 38.9–68.6 mm SL, rio Salobra, -20.78027, -56.74194, 3 Sep 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 4748, 4, 91.4 –219.0 mm SL, rio Salobra, -20.78166, -56.74194, 3 Sep 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. LIRP 5241, 6, 212.0– 256.7 mm SL, Bonito, córrego Mutum, -21.30083, -56.43583, 19 Aug 2004, H. F. dos Santos, O. Froehlich & R. Castro. ZUFMS 895, 6, 18.2–81.4 mm SL, córrego Azul e rio Salobra, 9 Apr 2000, O. Froehlich. ZUFMS 1191, 1, 16.6 mm SL, córrego Azul, -20.7588, -56.75183, 9 Apr 2000, L. S. Inocêncio, M. R. Cavallaro, F. M. Carvalho, F. M. Fernandes & F. Silva. ZUFMS 1631, 2, 27.0– 31.9 mm SL, córrego Azul, -20.75883, -56.75183, 9 Apr 2000, O. Froehlich. ZUFMS 2554, 2, 60.0– 60.5 mm SL, stream tributary of the rio Salobra, -20.77439, -56.73683, 5 Sep 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 3606, 8, 121.0–188.0 mm SL, Bonito, córrego Taquaral, -21.10833, -56.63277, 4 Feb 2013, Severo-Neto, F. ZUFMS 4747, 11, 67.7–121.4 mm SL, mouth of the córrego Paulista, -20.68555, -56.77805, 13 Aug 2001, O. Froehlich, M. R. Cavallaro & D. Silva. ZUFMS 786, 2, 51.6–93.2 mm SL, “Bodoquena”, 8 Apr 1998, P. R. Souza. NUP 13392, 4, 177.0– 200.7 mm SL, -20.683055, -56.78666, 27 Jul 2006, O. Froehlich et al. NUP 13387, 1, 187.3 mm SL, - 20.68305, -56.78666, Mar 2007, O. Froehlich et al. NUP 12142, 4, 127.8 –233.0 mm SL, -20.67, -56.77, Mar 2007, O. Froehlich et al. NUP 4247, 3, 106.1 – 132.9 mm SL, -20.68333, -56.78611, 31 Dec 2005, O. Froehlich et al. ZUFMS 896, 24, 24.6–73.9 mm SL, -20.68333, -56.78611, 20 May 2000, O. Froehlich. ZUFMS 1064, 4, 66.4–95.9 mm SL, -20.68333, -56.78611, 16 Jun 2001, O. Froehlich & M. R. Cavallaro. ZUFMS 1172, 13, 39.2–65.5 mm SL, -20.68333, -56.78611, 20 May 2000, O. Froehlich, M. R. Cavallaro, F. M. Fernandes, L. N. Carvalho & L. S. Inocêncio. ZUFMS 1173, 2, 72.8 –77.0 mm SL, -20.68333, -56.78611, 27 Feb 2000, O. Froehlich, M. R. Cavallaro, R. S. Arruda, L. S. Inocêncio, L. P. C. Lopes & R. Diniz. ZUFMS 1178, 1, 65.4 mm SL, -20.68333, -56.78611, 11 Jul 2001, F. Silva, M. R. Cavallaro & L. S. Inocêncio. ZUFMS 1180, 90, 27.1–67.8 mm SL, -20.683333, -56.78611, 9 Sep 2000, O. Froehlich, M. R. Cavallaro, D. Silva, A. Fecchio, J. Sedenho & L. S. Inocêncio. ZUFMS 1182, 15, 30.0– 108.6 mm SL, -20.68333, -56.786111, 26 Feb 2001, O. Froehlich, L. S. Inocêncio, L. P. C. Lopes & R. Diniz. ZUFMS 1185, 1, 24.5 mm SL, -20.68333, -56.78611, 27 Feb 2001, O. Froehlich, D. Silva, L. S. Inocêncio, L. P. C. Lopes & R. D. R. Diniz. ZUFMS 1187, 3, 67.2–74.4 mm SL, -20.68333, -56.786111, 13 Aug 2001, O. Froehlich, M. R. Cavallaro & L. S. Inocêncio. ZUFMS 1203, 1, 34.4 mm SL, -20.68333, -56.78611, 20 May 2001, O. Froehlich, M. R. Cavallaro, R. Arruda, L. A. Espíndola, D. M. Alves & F. M. Fernandes. ZUFMS 1461, 40, 25.5–53.3 mm SL, -20.68333, -56.78611, 9 Sep 2001, M. R. Cavallaro, J. Sedenho, E. Amorim & L. P. C. Lopes. ZUFMS 1474, 27, 25.6 –66.0 mm SL, -20.68333, -56.78611, 9 Sep 2001, M. R. Cavallaro, J. Sedenho, E. Amorim & L. P. C. Lopes. ZUFMS 1619, 13, 26.2–50.5 mm SL, -20.68333, -56.786111, 20 May 2000, O. Froehlich. ZUFMS 2539, 1, 50.7 mm SL, -20.68555, -56.77888, 2 Sep 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 2544, 2, 11.1 –45.0 mm SL, -- 20.68583, -56.78333, 2005, M. R. Cavallaro, M. J. A. Vilela, N. V. A. Almeida, O. Froehlich & R. D. Vargas. ZUFMS 2579, 7, 22.8–64.3 mm SL, -20.68333, -56.78583, 2005, M. R. Cavallaro, M. J. A. Vilela, N. V. A. Almeida, O. Froehlich & R. D. Vargas. ZUFMS 2594, 7, 16.8–53.6 mm SL, -20.68583, -56.78333, 2005, M. R. Cavallaro, M. J. A. Vilela, N. V. A. Almeida, O. Froehlich & R. D. Vargas. ZUFMS 2636, 20, 21.2 –195.0 mm SL, -20.68583, -56.78333, 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 3276, 2, 71.3 –75.0 mm SL, -20.682778, -56.7775, 27 Feb 2001, O. Froehlich. ZUFMS 4664, 4, 29.3–78.9 mm SL, -20.68305, -56.78638, 26 Jul 2006, O. Froehlich, F. Severo-Neto, M. C. Teixeira, M. O. Tanaka, M. R. Cavallaro, M. Beccari & T. T. M. Taveira. ZUFMS 4693, 1, 208.0 mm SL, -20.68361, -56.78527, 27 Jul 2006, O. Froehlich, F. Severo-Neto, M. C. Teixeira, M. O. Tanaka, M. R. Cavallaro, M. Beccari & T. T. M. Taveira. ZUFMS 4730, 12, 73.2 –181.0 mm SL, -20.68305, -56.78638, 26 Jul 2006, O. Froehlich, F. Severo-Neto, M. C. Teixeira, M. O. Tanaka, M. R. Cavallaro, M. Beccari & T. T. M. Taveira. ZUFMS 4750, 1, 171.0 mm SL, -20.68361, -56.78527, 27 Jul 2006, O. Froehlich, F. Severo-Neto, M. C. Teixeira, M. O. Tanaka, M. R. Cavallaro, M. Beccari & T. T. M. Taveira. ZUFMS 5230, 30, 24.0– 91.3 mm SL, -20.68333, -56.78611, 31 Aug 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. Diagnosis. Hypostomus froehlichi is distinguished from the species of the H. cochliodon group (sensu Zawadzki & Hollanda Carvalho, 2014) by having villiform teeth and angle between dentaries usually larger than 80° (vs. spoon-or shovel-shaped teeth and angle between dentaries about 80°); from H. affinis, H. ancistroides, H. arecuta, H. argus, H. aspilogaster, H. borellii, H. boulengeri, H. carinatus, H. careopinnatus, H. carvalhoi, H. commersoni, H. crassicauda, H. delimai, H. derbyi, H. dlouhyi, H. faveolus, H. formosae, H. hemiurus, H. interruptus, H. itacua, H. laplatae, H. niceforoi, H. nigrolineatus, H. nigropunctatus, H. nudiventris, H. paucimaculatus, H. piratatu, H. plecostomus, H. pantherinus, H. punctatus, H. pusarum, H. scabryceps, H. seminudus, H. spiniger, H. subcarinatus, H. tapijara, H. variostictus, H. velhochico and H. watwata by lacking keels on lateral series of plates (vs. having moderate or strong keels along lateral series of plates); from H. alatus, H. albopunctatus, H. francisci, H. luteomaculatus, H. luteus, H. margaritifer, H. meleagris, H. microstomus, H. multidens, H. myersi, H. regani, H. roseopunctatus, H. sertanejo, H. strigaticeps, H. tietensis and H. variipictus by having dark blotches on a clearer background (vs. pale spots or vermiculations on a darker background); from H. isbrueckeri by having caudal fin with dark blotches (vs caudal fin homogeneously dark or often with yellow distal band in mature males); from H. laplatae by having from 24 to 27 plates on lateral series (vs. 31); from H. latifrons by having juveniles with dark blotches on flanks (vs. juveniles with dark saddles); from H. uruguayensis by having shorter unbranched caudalfin rays—ventral unbranched caudal-fin ray similar in length to head length (vs. similar to predorsal length); it is additionally diagnosed from H. isbrueckeri, H. laplatae, H. latifrons, and H. uruguayensis by usually having one plate bordering supraoccipital (vs. three to seven). Hypostomus froehlichi is distinguished from H. denticulatus by having lower number of teeth, 10–61 (vs. more than 100 teeth); from H. brevis, H. paulinus, H. mutucae, and H. nigromacutlatus by having anterior portion of abdomen totally covered by platelets (vs. abdomen mostly naked); from H. heraldoi by having pectoral-fin spine clearly longer than pelvic-fin spine (vs. pectoral-fin spine equal to or shorter than pelvic-fin spine); from H. iheringii, H. latirostris and H. ternetzi by having short ventral unbranched caudal-fin ray, its length usually similar to head length (vs. long, usually similar in length to predorsal distance); from H. hermanni and H. topavae by lacking dark stripe margining dorsal-fin branched rays anteriorly (vs. dorsal fin with longitudinal inconspicuous dark stripe anteriorly margining branched rays); from H. renestoi and H. yaku by lacking hypertrophied odontodes along dorsal and mid-dorsal series of plates (vs. having moderately developed odontodes in H. renestoi —see Zawadzki et al. 2018, Fig. 9b to highly developed hypertrophied odontodes on caudal portions of lateral series of plates in H. yaku, see Martins et al. 2014, Fig. 2). Description. Morphometric data in Tables 1. Overall view of body in Fig. 1. Head broad and stout. Snout and anterior profile of head rounded in dorsal view. Eye of moderate size, dorsolaterally positioned. Dorsal margin of orbit not or very slightly raised. Body width at cleithral region much larger than head depth and approximately equal to head length. Greatest body width at cleithrum, narrowing from dorsal-fin region to caudal-fin origin. Dorsal profile of head straight from snout tip to vertical through interorbital region angling about 35° with ventral region of head; slightly convex from that point to dorsal-fin origin; straight to first procurrent rays of dorsal fin; raising again to caudal fin. Ventral profile almost straight from snout tip to insertion of pelvic-fin unbranched ray; straight and slightly narrowing from pelvic-fin insertion to ventral caudal-fin procurrent rays. Caudal peduncle slightly compressed anteriorly; moderate to strongly compressed posteriorly. Plates along mesethmoid forming longitudinal bulge from snout tip to nares, more conspicuous in specimens up to 100 mm SL (NUP 4247); in larger specimens depending on fixation. Supraoccipital with very slight median bulge; its short posterior process bordered by single plate. Moderate bulge originating lateral to nares, passing through supraorbital, and weakly extending along dorsal portion of pterotic-supracleithrum. Opercle large; horizontal length similar to or slightly larger than orbital diameter. Oral disk round, moderate in size; margins smooth. Lower lip not reaching transverse line through gill openings. Odontodes on anterior portion of upper lip. Upper lip ventrally covered with transverse papilla. Lower lip ventral surface covered with numerous small round papillae, larger proximally. Maxillary barbel usually small, from half to slightly smaller than eye diameter; usually mostly coadnate to lower lip by membrane. Median buccal papilla large, its tip rough. Smaller buccal papillae along internal margins of each dentary and mandibullary ramus. Dentaries moderate to strongly angled, averaging from 108° to 137° between left and right dentary rami. Teeth viliform, bicuspid; crowns bent ventrally. Crowns with main cusp lanceolate and smaller pointed lateral cusp. Some specimens with 14–17 shorter and robust teeth bearing a proportionally smaller lateral cusp (NUP 12139, 223.0 mm SL), while some other specimens with 55–61 slightly longer, thinner and viliform teeth (NUP 12140, 241.8 mm SL). Holotype and several other specimens with about 32–37 moderate viliform teeth. Body covered with five rows of dermal plates with weakly-developed odontodes, except one small naked area on snout tip and on base of dorsal fin. Predorsal region with very slight median keel. Dorsal series of plates with moderate keels. Dorsal series strongly bent on interdorsal region resulting in anterodorsal surface of caudal peduncle strongly flat. Mid-dorsal and median series without keels. Median series bearing continuous lateral line. Mid-ventral series strongly angled from first to third or fourth plates. Ventral series bent ventrally resulting in flat caudal peduncle floor. Ventral surface of head and abdomen naked in specimens up to 80 mm SL (NUP 5077). In larger specimens, abdomen completely covered with platelets on anterior portion and with naked areas around ventral-fin origins. Dorsal fin II,7; origin at vertical through posterior two third between pectoral- and pelvic-fin insertions. First spine as functional spinelet. Second spine bearing dorsal fin; flexible. Distal margin of dorsal fin slightly convex; tip of last dorsal-fin branched rays from almost to just reaching adipose-fin spine. Adipose-fin spine compressed and slightly curved inward. Adipose-fin spine tip reaching forth to fifth plate after origin. Pectoral fin I,6; distal bor-der straight. Pectoral-fin spine slightly curved inward, slightly depressed proximally, round distally; covered with developed odontodes, more developed on distal portion, particularly in larger specimens. Odontodes from pectoral spine curved proximally. Distal region of pectoral fin with swollen skin usually forming tissue sheath around emerging odontodes. Tip of adpressed pectoral fin reaching about one-third of adpressed pelvic-fin spine. Pelvic fin i,5; distal border straight to slightly convex; when adpressed unbranched ray surpassing anal-fin origin. Anal fin i,4; tip reaching fifth plate after origin. All anal-fin rays similar in length. Caudal fin i,14,i; posterior margin falcate, with ventral lobe slightly longer than dorsal. Color in alcohol. Dorsolateral ground color of head, trunk and fins brown to grayish-brown and covered with many large faded dark blotches (Fig. 1). Dark blotches numerous, close to each other and varying in size from slightly smaller to slightly larger than eye pupil diameter in head. Blotches larger on trunk and fins, varying from slightly larger than eye pupil diameter to similar to eye diameter. Blotch diameters and distances to each other relatively constant along anteroposterior axis of trunk. Space between each blotch usually smaller than diameter of blotches. Dorsal, pectoral and ventral fins usually with one row of blotches on each interadial membrane in specimens up to 100 mm SL; usually with two rows of blotches along each interadial membrane in specimens larger than 100 mm SL. Some specimens with blotches fused to each other forming from two or three irregular lines on proximal region of dorsal fin. Anal and caudal fins usually with one row of blotch per interadial membrane; anal and caudal fins blurred in some specimens. Ventral surface beige, usually lacking blotches. Blotches progressively faded along time of preservation of specimens, and almost or totally absent in old preserved specimens. Teeth with pale stalks and orange crowns. Color in life. Color pattern of living specimens similar to preserved ones, except for clearer and bright background color, with more conspicuous black blotches (Figs. 2, 3, 4). According to underwater observations of P. Petersen (pers. comm.), the specimens ranging from 20.0 to 40.0 mm TL displayed a very peculiar color pattern, with slightly yellow to orange fins. At around 50.0 mm TL, the yellow/orange colors fade and the typical rounded dark blotches begin to appear (Fig. 4). Sexual dimorphism. No external sexual dimorphism was observed among the analyzed specimens. Geographical distribution. Hypostomus froehlichi is currently known from the following tributaries of the rio Miranda basin, a tributary of the rio Paraguay basin: córrego Salobrinha, its type-locality, córrego Azul, córrego Mutum, córrego Paulista, córrego Taquaral, rio Formoso, and rio Salobra. Additionally, photographic records by both Marcelo Krause and Peter Petersen confirmed the occurrence of the new species in the Mimoso and da Prata rivers, also tributaries of the rio Miranda basin. All known records are within the Bodoquena Plateau region, Mato Grosso do Sul, Brazil (Fig. 5). Natural history notes. According to Penatti (2010), young specimens of Hypostomus froehlichi were obser

Hypostomus froehlichi, new species (Figs. 1���4 and 6, Table 1 and 2) Holotype. NUP 22689, 226.2 mm SL, Bodoquena, Mato Grosso do Sul State, Brazil, c��rrego Salobrinha, tributary of rio Miranda, rio Paraguay basin, -20.68273, -56.78600, Mar 2007, O. Froehlich et al. Paratypes. All from Brazil, Mato Grosso do Sul State, Bodoquena, rio Paraguay basin, c��rrego Salobrinha, except when indicated: LIRP 5226, 5, 115.8 ��� 128.6 mm SL, Bonito, rio Formoso, -21.07916, -56.33916, 29 Aug 2004, H. F. dos Santos, O. Froehlich & R. Castro. LIRP 5228, 3, 163.1 ��� 222.2 mm SL, rio Salobra, -20.53860, -56.71500, 2 Sep 2004, H. F. dos Santos, O. Froehlich & R. Castro. LIRP 5240, 39, 25.6 ���209.0 mm SL, rio Salobra, -20.53860, -56.71500, 22 Aug 2004, H. F. dos Santos, O. Froehlich & R. Castro. LIRP 5242, 2, 231.2 ��� 232.5 mm SL, rio Salobra -20.73805, -56.73472, 22 Aug 2004, H. F. dos Santos, O. Froehlich & R. Castro. NUP 5077, 5, 52.2���201.1 mm SL, rio Salobra, -20.49555, -56.86333, 27 Dec 2006, A. G. Bifi. NUP 12138, 2, 235.3 ��� 239.1 mm SL, rio Salobra, -20.78027, -56.74194, Dec 2005, O. Froehlich et al. NUP 12139, 2, 223.0��� 227.8 mm SL, rio Salobra, -20.78027, -56.74194, Dec 2005, O. Froehlich et al. NUP 12140, 2, 235.3 ��� 241.8 mm SL, rio Salobra, -20.78027, -56.74194, Dec 2005, O. Froehlich et al. NUP 12141, 1, 225.0 mm SL, rio Salobra, -20.78027, -56.74194, Dec 2005, O. Froehlich et al. ZUFMS 904, 18, 20.5���78.2 mm SL, rio Salobra, -20.67527, -56.75694, 13 May 2001, O. Froehlich, M. R. Cavallaro & J. Sedenho. ZUFMS 1024, 14, 25.5 ���74.0 mm SL, rio Salobra, -20.67527, -56.75694, 28 Jun 2001, O. Froehlich. ZUFMS 1085, 2, 51.6���66.5 mm SL, rio Salobra, -20.67527, -56.75694, 10 Oct 2001, O. Froehlich, E. Amorim, M. V. Costa & L. P. C. Lopes. ZUFMS 1126, 127, 21.2 ���122.0 mm SL, rio Salobra, -20.67527, -56.75694, 13 Oct 2001, O. Froehlich, M. V. Costa & L. P. C. Lopes. ZUFMS 1171, 6, 11.5���61.7 mm SL, rio Salobra, -20.67527, -56.75694, 10 Sep 2001, O. Froehlich, M. R. Cavallaro, F. M. Fernandes, L. N. Carvalho & L. S. Inoc��ncio. ZUFMS 1175, 89, 18.7���56.4 mm SL, rio Salobra, -20.67527, -56.75694, 21 May 2000, O. Froehlich, M. R. Cavallaro, R. S. Arruda, D. Silva & L. S. Inoc��ncio. ZUFMS 1179, 83, 16.1���65.2 mm SL, rio Salobra, -20.67527, -56.75694, 14 May 2001, L.S. Inoc��ncio, M. R. Cavallaro, O. Froehlich & J. Sedenho. ZUFMS 1183, 1, 40.4 mm SL, rio Salobra, -20.67527, -56.75694, 21 May 2000, O. Froehlich. ZUFMS 1186, 3, 10.6���15.1 mm SL, rio Salobra, -20.67527, -56.75694, 8 Jun 2000, O. Froehlich. ZUFMS 1190, 1, 35.3 mm SL, rio Salobra, -20.67527, -56.75694, 20 May 2000, O. Froehlich. ZUFMS 1545, 34, 28.5���65.8 mm SL, rio Salobra, -20.67527, -56.75694, 10 Sep 2000, O. Froehlich. ZUFMS 2525, 41, 12.8���50.6 mm SL, rio Salobra, -20.78166, -56.74194, 3 Sep 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 2590, 9, 33.3���46.5 mm SL, rio Salobra, -20.67, -56.76055, 30 Aug 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 4470, 38.9���68.6 mm SL, rio Salobra, -20.78027, -56.74194, 3 Sep 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 4748, 4, 91.4 ���219.0 mm SL, rio Salobra, -20.78166, -56.74194, 3 Sep 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. LIRP 5241, 6, 212.0��� 256.7 mm SL, Bonito, c��rrego Mutum, -21.30083, -56.43583, 19 Aug 2004, H. F. dos Santos, O. Froehlich & R. Castro. ZUFMS 895, 6, 18.2���81.4 mm SL, c��rrego Azul e rio Salobra, 9 Apr 2000, O. Froehlich. ZUFMS 1191, 1, 16.6 mm SL, c��rrego Azul, -20.7588, -56.75183, 9 Apr 2000, L. S. Inoc��ncio, M. R. Cavallaro, F. M. Carvalho, F. M. Fernandes & F. Silva. ZUFMS 1631, 2, 27.0��� 31.9 mm SL, c��rrego Azul, -20.75883, -56.75183, 9 Apr 2000, O. Froehlich. ZUFMS 2554, 2, 60.0��� 60.5 mm SL, stream tributary of the rio Salobra, -20.77439, -56.73683, 5 Sep 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 3606, 8, 121.0���188.0 mm SL, Bonito, c��rrego Taquaral, -21.10833, -56.63277, 4 Feb 2013, Severo-Neto, F. ZUFMS 4747, 11, 67.7���121.4 mm SL, mouth of the c��rrego Paulista, -20.68555, -56.77805, 13 Aug 2001, O. Froehlich, M. R. Cavallaro & D. Silva. ZUFMS 786, 2, 51.6���93.2 mm SL, ���Bodoquena���, 8 Apr 1998, P. R. Souza. NUP 13392, 4, 177.0��� 200.7 mm SL, -20.683055, -56.78666, 27 Jul 2006, O. Froehlich et al. NUP 13387, 1, 187.3 mm SL, - 20.68305, -56.78666, Mar 2007, O. Froehlich et al. NUP 12142, 4, 127.8 ���233.0 mm SL, -20.67, -56.77, Mar 2007, O. Froehlich et al. NUP 4247, 3, 106.1 ��� 132.9 mm SL, -20.68333, -56.78611, 31 Dec 2005, O. Froehlich et al. ZUFMS 896, 24, 24.6���73.9 mm SL, -20.68333, -56.78611, 20 May 2000, O. Froehlich. ZUFMS 1064, 4, 66.4���95.9 mm SL, -20.68333, -56.78611, 16 Jun 2001, O. Froehlich & M. R. Cavallaro. ZUFMS 1172, 13, 39.2���65.5 mm SL, -20.68333, -56.78611, 20 May 2000, O. Froehlich, M. R. Cavallaro, F. M. Fernandes, L. N. Carvalho & L. S. Inoc��ncio. ZUFMS 1173, 2, 72.8 ���77.0 mm SL, -20.68333, -56.78611, 27 Feb 2000, O. Froehlich, M. R. Cavallaro, R. S. Arruda, L. S. Inoc��ncio, L. P. C. Lopes & R. Diniz. ZUFMS 1178, 1, 65.4 mm SL, -20.68333, -56.78611, 11 Jul 2001, F. Silva, M. R. Cavallaro & L. S. Inoc��ncio. ZUFMS 1180, 90, 27.1���67.8 mm SL, -20.683333, -56.78611, 9 Sep 2000, O. Froehlich, M. R. Cavallaro, D. Silva, A. Fecchio, J. Sedenho & L. S. Inoc��ncio. ZUFMS 1182, 15, 30.0��� 108.6 mm SL, -20.68333, -56.786111, 26 Feb 2001, O. Froehlich, L. S. Inoc��ncio, L. P. C. Lopes & R. Diniz. ZUFMS 1185, 1, 24.5 mm SL, -20.68333, -56.78611, 27 Feb 2001, O. Froehlich, D. Silva, L. S. Inoc��ncio, L. P. C. Lopes & R. D. R. Diniz. ZUFMS 1187, 3, 67.2���74.4 mm SL, -20.68333, -56.786111, 13 Aug 2001, O. Froehlich, M. R. Cavallaro & L. S. Inoc��ncio. ZUFMS 1203, 1, 34.4 mm SL, -20.68333, -56.78611, 20 May 2001, O. Froehlich, M. R. Cavallaro, R. Arruda, L. A. Esp��ndola, D. M. Alves & F. M. Fernandes. ZUFMS 1461, 40, 25.5���53.3 mm SL, -20.68333, -56.78611, 9 Sep 2001, M. R. Cavallaro, J. Sedenho, E. Amorim & L. P. C. Lopes. ZUFMS 1474, 27, 25.6 ���66.0 mm SL, -20.68333, -56.78611, 9 Sep 2001, M. R. Cavallaro, J. Sedenho, E. Amorim & L. P. C. Lopes. ZUFMS 1619, 13, 26.2���50.5 mm SL, -20.68333, -56.786111, 20 May 2000, O. Froehlich. ZUFMS 2539, 1, 50.7 mm SL, -20.68555, -56.77888, 2 Sep 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 2544, 2, 11.1 ���45.0 mm SL, -- 20.68583, -56.78333, 2005, M. R. Cavallaro, M. J. A. Vilela, N. V. A. Almeida, O. Froehlich & R. D. Vargas. ZUFMS 2579, 7, 22.8���64.3 mm SL, -20.68333, -56.78583, 2005, M. R. Cavallaro, M. J. A. Vilela, N. V. A. Almeida, O. Froehlich & R. D. Vargas. ZUFMS 2594, 7, 16.8���53.6 mm SL, -20.68583, -56.78333, 2005, M. R. Cavallaro, M. J. A. Vilela, N. V. A. Almeida, O. Froehlich & R. D. Vargas. ZUFMS 2636, 20, 21.2 ���195.0 mm SL, -20.68583, -56.78333, 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. ZUFMS 3276, 2, 71.3 ���75.0 mm SL, -20.682778, -56.7775, 27 Feb 2001, O. Froehlich. ZUFMS 4664, 4, 29.3���78.9 mm SL, -20.68305, -56.78638, 26 Jul 2006, O. Froehlich, F. Severo-Neto, M. C. Teixeira, M. O. Tanaka, M. R. Cavallaro, M. Beccari & T. T. M. Taveira. ZUFMS 4693, 1, 208.0 mm SL, -20.68361, -56.78527, 27 Jul 2006, O. Froehlich, F. Severo-Neto, M. C. Teixeira, M. O. Tanaka, M. R. Cavallaro, M. Beccari & T. T. M. Taveira. ZUFMS 4730, 12, 73.2 ���181.0 mm SL, -20.68305, -56.78638, 26 Jul 2006, O. Froehlich, F. Severo-Neto, M. C. Teixeira, M. O. Tanaka, M. R. Cavallaro, M. Beccari & T. T. M. Taveira. ZUFMS 4750, 1, 171.0 mm SL, -20.68361, -56.78527, 27 Jul 2006, O. Froehlich, F. Severo-Neto, M. C. Teixeira, M. O. Tanaka, M. R. Cavallaro, M. Beccari & T. T. M. Taveira. ZUFMS 5230, 30, 24.0��� 91.3 mm SL, -20.68333, -56.78611, 31 Aug 2005, M. J. A. Vilela, O. Froehlich, O. C. Forster & R. D. Vargas. Diagnosis. Hypostomus froehlichi is distinguished from the species of the H. cochliodon group (sensu Zawadzki & Hollanda Carvalho, 2014) by having villiform teeth and angle between dentaries usually larger than 80�� (vs. spoon-or shovel-shaped teeth and angle between dentaries about 80��); from H. affinis, H. ancistroides, H. arecuta, H. argus, H. aspilogaster, H. borellii, H. boulengeri, H. carinatus, H. careopinnatus, H. carvalhoi, H. commersoni, H. crassicauda, H. delimai, H. derbyi, H. dlouhyi, H. faveolus, H. formosae, H. hemiurus, H. interruptus, H. itacua, H. laplatae, H. niceforoi, H. nigrolineatus, H. nigropunctatus, H. nudiventris, H. paucimaculatus, H. piratatu, H. plecostomus, H. pantherinus, H. punctatus, H. pusarum, H. scabryceps, H. seminudus, H. spiniger, H. subcarinatus, H. tapijara, H. variostictus, H. velhochico and H. watwata by lacking keels on lateral series of plates (vs. having moderate or strong keels along lateral series of plates); from H. alatus, H. albopunctatus, H. francisci, H. luteomaculatus, H. luteus, H. margaritifer, H. meleagris, H. microstomus, H. multidens, H. myersi, H. regani, H. roseopunctatus, H. sertanejo, H. strigaticeps, H. tietensis and H. variipictus by having dark blotches on a clearer background (vs. pale spots or vermiculations on a darker background); from H. isbrueckeri by having caudal fin with dark blotches (vs caudal fin homogeneously dark or often with yellow distal band in mature males); from H. laplatae by having from 24 to 27 plates on lateral series (vs. 31); from H. latifrons by having juveniles with dark blotches on flanks (vs. juveniles with dark saddles); from H. uruguayensis by having shorter unbranched caudalfin rays���ventral unbranched caudal-fin ray similar in length to head length (vs. similar to predorsal length); it is additionally diagnosed from H. isbrueckeri, H. laplatae, H. latifrons, and H. uruguayensis by usually having one plate bordering supraoccipital (vs. three to seven). Hypostomus froehlichi is distinguished from H. denticulatus by having lower number of teeth, 10���61 (vs. more than 100 teeth); from H. brevis, H. paulinus, H. mutucae, and H. nigromacutlatus by having anterior portion of abdomen totally covered by platelets (vs. abdomen mostly naked); from H. heraldoi by having pectoral-fin spine clearly longer than pelvic-fin spine (vs. pectoral-fin spine equal to or shorter than pelvic-fin spine); from H. iheringii, H. latirostris and H. ternetzi by having short ventral unbranched caudal-fin ray, its length usually similar to head length (vs. long, usually similar in length to predorsal distance); from H. hermanni and H. topavae by lacking dark stripe margining dorsal-fin branched rays anteriorly (vs. dorsal fin with longitudinal inconspicuous dark stripe anteriorly margining branched rays); from H. renestoi and H. yaku by lacking hypertrophied odontodes along dorsal and mid-dorsal series of plates (vs. having moderately developed odontodes in H. renestoi ���see Zawadzki et al. 2018, Fig. 9b to highly developed hypertrophied odontodes on caudal portions of lateral series of plates in H. yaku, see Martins et al. 2014, Fig. 2). Description. Morphometric data in Tables 1. Overall view of body in Fig. 1. Head broad and stout. Snout and anterior profile of head rounded in dorsal view. Eye of moderate size, dorsolaterally positioned. Dorsal margin of orbit not or very slightly raised. Body width at cleithral region much larger than head depth and approximately equal to head length. Greatest body width at cleithrum, narrowing from dorsal-fin region to caudal-fin origin. Dorsal profile of head straight from snout tip to vertical through interorbital region angling about 35�� with ventral region of head; slightly convex from that point to dorsal-fin origin; straight to first procurrent rays of dorsal fin; raising again to caudal fin. Ventral profile almost straight from snout tip to insertion of pelvic-fin unbranched ray; straight and slightly narrowing from pelvic-fin insertion to ventral caudal-fin procurrent rays. Caudal peduncle slightly compressed anteriorly; moderate to strongly compressed posteriorly. Plates along mesethmoid forming longitudinal bulge from snout tip to nares, more conspicuous in specimens up to 100 mm SL (NUP 4247); in larger specimens depending on fixation. Supraoccipital with very slight median bulge; its short posterior process bordered by single plate. Moderate bulge originating lateral to nares, passing through supraorbital, and weakly extending along dorsal portion of pterotic-supracleithrum. Opercle large; horizontal length similar to or slightly larger than orbital diameter. Oral disk round, moderate in size; margins smooth. Lower lip not reaching transverse line through gill openings. Odontodes on anterior portion of upper lip. Upper lip ventrally covered with transverse papilla. Lower lip ventral surface covered with numerous small round papillae, larger proximally. Maxillary barbel usually small, from half to slightly smaller than eye diameter; usually mostly coadnate to lower lip by membrane. Median buccal papilla large, its tip rough. Smaller buccal papillae along internal margins of each dentary and mandibullary ramus. Dentaries moderate to strongly angled, averaging from 108�� to 137�� between left and right dentary rami. Teeth viliform, bicuspid; crowns bent ventrally. Crowns with main cusp lanceolate and smaller pointed lateral cusp. Some specimens with 14���17 shorter and robust teeth bearing a proportionally smaller lateral cusp (NUP 12139, 223.0 mm SL), while some other specimens with 55���61 slightly longer, thinner and viliform teeth (NUP 12140, 241.8 mm SL). Holotype and several other specimens with about 32���37 moderate viliform teeth. Body covered with five rows of dermal plates with weakly-developed odontodes, except one small naked area on snout tip and on base of dorsal fin. Predorsal region with very slight median keel. Dorsal series of plates with moderate keels. Dorsal series strongly bent on interdorsal region resulting in anterodorsal surface of caudal peduncle strongly flat. Mid-dorsal and median series without keels. Median series bearing continuous lateral line. Mid-ventral series strongly angled from first to third or fourth plates. Ventral series bent ventrally resulting in flat caudal peduncle floor. Ventral surface of head and abdomen naked in specimens up to 80 mm SL (NUP 5077). In larger specimens, abdomen completely covered with platelets on anterior portion and with naked areas around ventral-fin origins. Dorsal fin II,7; origin at vertical through posterior two third between pectoral- and pelvic-fin insertions. First spine as functional spinelet. Second spine bearing dorsal fin; flexible. Distal margin of dorsal fin slightly convex; tip of last dorsal-fin branched rays from almost to just reaching adipose-fin spine. Adipose-fin spine compressed and slightly curved inward. Adipose-fin spine tip reaching forth to fifth plate after origin. Pectoral fin I,6; distal bor-der straight. Pectoral-fin spine slightly curved inward, slightly depressed proximally, round distally; covered with developed odontodes, more developed on distal portion, particularly in larger specimens. Odontodes from pectoral spine curved proximally. Distal region of pectoral fin with swollen skin usually forming tissue sheath around emerging odontodes. Tip of adpressed pectoral fin reaching about one-third of adpressed pelvic-fin spine. Pelvic fin i,5; distal border straight to slightly convex; when adpressed unbranched ray surpassing anal-fin origin. Anal fin i,4; tip reaching fifth plate after origin. All anal-fin rays similar in length. Caudal fin i,14,i; posterior margin falcate, with ventral lobe slightly longer than dorsal. Color in alcohol. Dorsolateral ground color of head, trunk and fins brown to grayish-brown and covered with many large faded dark blotches (Fig. 1). Dark blotches numerous, close to each other and varying in size from slightly smaller to slightly larger than eye pupil diameter in head. Blotches larger on trunk and fins, varying from slightly larger than eye pupil diameter to similar to eye diameter. Blotch diameters and distances to each other relatively constant along anteroposterior axis of trunk. Space between each blotch usually smaller than diameter of blotches. Dorsal, pectoral and ventral fins usually with one row of blotches on each interadial membrane in specimens up to 100 mm SL; usually with two rows of blotches along each interadial membrane in specimens larger than 100 mm SL. Some specimens with blotches fused to each other forming from two or three irregular lines on proximal region of dorsal fin. Anal and caudal fins usually with one row of blotch per interadial membrane; anal and caudal fins blurred in some specimens. Ventral surface beige, usually lacking blotches. Blotches progressively faded along time of preservation of specimens, and almost or totally absent in old preserved specimens. Teeth with pale stalks and orange crowns. Color in life. Color pattern of living specimens similar to preserved ones, except for clearer and bright background color, with more conspicuous black blotches (Figs. 2, 3, 4). According to underwater observations of P. Petersen (pers. comm.), the specimens ranging from 20.0 to 40.0 mm TL displayed a very peculiar color pattern, with slightly yellow to orange fins. At around 50.0 mm TL, the yellow/orange colors fade and the typical rounded dark blotches begin to appear (Fig. 4). Sexual dimorphism. No external sexual dimorphism was observed among the analyzed specimens. Geographical distribution. Hypostomus froehlichi is currently known from the following tributaries of the rio Miranda basin, a tributary of the rio Paraguay basin: c��rrego Salobrinha, its type-locality, c��rrego Azul, c��rrego Mutum, c��rrego Paulista, c��rrego Taquaral, rio Formoso, and rio Salobra. Additionally, photographic records by both Marcelo Krause and Peter Petersen confirmed the occurrence of the new species in the Mimoso and da Prata rivers, also tributaries of the rio Miranda basin. All known records are within the Bodoquena Plateau region, Mato Grosso do Sul, Brazil (Fig. 5). Natural history notes. According to Penatti (2010), young specimens of Hypostomus froehlichi were obser, Published as part of Zawadzki, Cl��udio H., Nardi, Gabriela & Tencatt, Luiz Fernando Caserta, 2021, The crystalline waters of the Bodoquena Plateau revealed Hypostomus froehlichi (Siluriformes: Loricariidae), a new armored catfish from the rio Paraguay basin in Brazil, pp. 98-112 in Zootaxa 4933 (1) on pages 99-108, DOI: 10.11646/zootaxa.4933.1.4, http://zenodo.org/record/4548024, {"references":["Zawadzki, C. H., Silva, H. P. & Troy, W. P. (2018) Redescription of Hypostomus latirostris (Regan, 1904) with the recognition of a new species of Hypostomus (Siluriformes: Loricariidae) from the upper Rio Paraguay basin, Brazil. Ichthyological Exploration of Freshwaters, IEF- 1079, 1 - 18.","Martins, F. O., Langeani, F. & Zawadzki, C. H. (2014) A new spiny species of Hypostomus Lacepede (Loricariidae: Hypostominae) from thermal waters, upper rio Parana basin, central Brazil Neotropical Ichthyology, 12 (4), 729 - 736. https: // doi. org / 10.1590 / 1982 - 0224 - 20140035","Penatti, N. C. (2010) Distribuicao espacial de cascudos (Loricariidae) evidencia controle por predacao e disponibilidade de alimento. Unpublished M. Sc. Dissertation, Universidade Federal de Mato Grosso do Sul, Campo Grande, 28 pp.","Froehlich, O. (2010) Ictiofauna de um corrego na Serra da Bodoquena: Estrutura, Variacles Longitudinal e Temporal e Efeitos sobre Comunidades Bentonicas. Unpublished Ph. D. Thesis, Universidade Federal de Mato Grosso do Sul, Campo Grande, 92 pp."]}

Aspidoras was described by Ihering as a monotypic genus to harbour A. rochai. Currently, the genus comprises 24 valid species, and is relatively well distributed across the Brazilian territory, occurring from São Paulo, its southernmost record, to Ceará. After its first taxonomic review provided by Nijssen & Isbrücker 40 years ago, no extensive work aiming to elucidate the taxonomy of Aspidoras was conducted. Therefore, a comprehensive taxonomic review was carried out, allowing the clear recognition of the genus through a new diagnosis that includes a possible exclusive feature, the presence of small laminar expansions on base of the pectoral-fin branched rays. Considering the new diagnosis plus the currently available phylogenetic data, A. pauciradiatus and A. virgulatus are herein excluded from Aspidoras, being transferred to Corydoras and Scleromystax, respectively. Regarding the remaining species, some new synonymies are proposed: A. eurycephalus and A. taurus with A. albater; A. menezesi and A. spilotus with A. raimundi; and A. microgaleus and A. marianae with A. poecilus. Additionally, a new species from the rivers Araguaia and Paraguay basins in Mato Grosso State is described. The new species can be distinguished from its congeners by having the combination of two features: parapophysis of the complex vertebra well developed, and anterior portion of infraorbital 1 with poorly-developed laminar expansion, slightly surpassing posterior margin of nasal capsule. Thereby, the number of valid species within Aspidoras was reduced from 24 to 17. Redescriptions for A. albater, A. belenos, A. depinnai, A. fuscoguttatus, A. lakoi, A. maculosus, A. poecilus, A. psammatides, A. raimundi and A. velites are provided. An identification key encompassing the species of Aspidoras, with exception of A. carvalhoi, is also provided. Aspidoras foi descrito por Ihering como um gênero monotípico para abrigar A. rochai. Atualmente, o gênero inclui 24 espécies válidas, sendo relativamente bem Distribuído ao longo do território brasileiro, ocorrendo de São Paulo, seu registro mais ao sul, até o Ceará. Após a primeira revisão taxonômica fornecida por Nijssen & Isbrücker 40 anos atrás, nenhum trabalho extensivo com o objetivo de elucidar a taxonomia de Aspidoras foi conduzido. Uma revisão taxonômica abrangente foi realizada para o reconhecimento claro do gênero através de uma nova diagnose, que inclui uma possível característica exclusiva, a presença de pequenas expansões laminares na base dos raios ramificados da nadadeira peitoral. Considerando a nova diagnose e os dados filogenéticos disponíveis atualmente, A. pauciradiatus e A. virgulatus foram excluídas de Aspidoras, sendo transferidas para Corydoras e Scleromystax, respectivamente. A respeito das demais espécies, algumas sinonímias novas são propostas: A. eurycephalus e A. taurus com A. albater; A. menezesi e A. spilotus com A. raimundi; e A. microgaleus e A. marianae com A. poecilus. Adicionalmente, uma espécie nova das bacias dos rios Araguaia e Paraguai no estado do Mato Grosso é descrita. A espécie nova pode ser distinguida de suas congeneres por apresentar a combinação de duas características: parapófise do complexo de vértebras bem desenvolvido, e porção anterior do infraorbital 1 com expansão laminar pouco desenvolvida, ligeiramente ultrapassando a margem posterior da cápsula nasal. Assim, o número de espécies válidas em Aspidoras foi reduzido de 24 para 17. Redescrições para A. albater, A. belenos, A. depinnai, A. fuscoguttatus, A. lakoi, A. maculosus, A. poecilus, A. psammatides, A. raimundi e A. velites foram fornecidas. Uma chave de identificação englobando as espécies de Aspidoras, com exceção de A. carvalhoi, também é fornecida. 60 f

Corydoras guapore Knaack, 1961 (Figs. 1-5; Table 1) Diagnosis. Corydoras guapore can be distinguished from its congeners, with exception of C. bilineatus, C. elegans, C. gracilis, C. mamore, C. nanus, C. napoensis, C. nijsseni, C. paucerna and C. undulatus, by having the following unique combination of features: mesethmoid short, with anterior tip poorly developed (vs. long, with well-developed anterior tip); serrations directed towards pectoral-spine origin (vs. perpendicularly inserted; or directed towards pectoral-spine tip); and conical serrations on posterior margin of pectoral spine (vs. laminar). Corydoras guapore can be distinguished from C. bilineatus, C. elegans, C. gracilis, C. mamore, C. nanus, C. napoensis, C. nijsseni, C. paucerna and C. undulatus by the presence of dorso- and ventrolateral body plates with vertically elongated or irregular brown blotches anteriorly to adipose fin, and lateral portion of caudal peduncle almost entirely blackened (vs. with two or three longitudinal black stripes in C. bilineatus, C. elegans, C. napoensis, C. undulatus; a thickened black stripe on dorsolateral body plates, ventrolateral body plates with irregular black spots in C. gracilis; irregular small black spots in C. mamore and C. paucerna; upper portion of dorsolateral body plates with intense black pigmentation, becoming diffuse toward ventrolateral body plates in C. nijsseni). Additionally, C. guapore can be distinguished from C. hastatus and C. pygmaeus by the presence of adipose fin with anterior portion hyaline and posterior portion blackened (vs. entirely hyaline); and the absence of a longitudinal black stripe on midline of flank (vs. presence of a slender diffuse longitudinal black stripe in C. hastatus; and a thicker conspicuous longitudinal black stripe in C. pygmaeus). Description. Morphometric data presented in Table 1. Head compressed with convex dorsal profile; somewhat pentagonal in dorsal view. Snout short and rounded. Head profile convex from tip of snout to anterior nares; and slightly concave from this point to the tip of posterior process of parieto-supraoccipital. Dorsal profile of body slightly convex along dorsal-fin base. Body profile nearly straight from posterior portion of dorsal-fin to adiposefin spine; markedly concave from this point to caudal-fin base. Ventral profile of body slightly convex from isthmus to pelvic girdle; nearly straight from pelvic girdle to base of first anal-fin ray; abruptly concave from this point to caudal-fin base. Body roughly elliptical in cross section at pectoral girdle, gradually becoming more compressed toward caudal fin. Eye rounded, located meso-laterally on head; orbit delimited dorsally by lateral ethmoid, frontal and sphenotic,ventrallybyinfraorbitals.Anteriorandposterior nares close to each other, only separated by flap of skin. Anterior naris tubular. Posterior naris relatively distant to antero-dorsal margin of orbit, separated from it by distance equal to twice the diameter of naris. Mouth small, subterminal, width nearly equal to bony orbit diameter. Maxillary barbel long in size, reaching anteroventral limit of gill opening. Outer mental barbel slightly smaller than maxillary barbel. Inner mental barbel fleshy, its base slightly separated from its counterpart. Small rounded papillae covering entire surface of all barbels, upper and lower lips, and isthmus. Mesethmoid short; anterior tip thickened and poorly developed, smaller than 50% of the bone length; with poorly-developed lateral cornua; posterior portion widened, partially exposed and bearing minute odontodes. Nasal slender, curved laterally, with inner margin laminar; posterior portion of outer margin laminar; mesial border contacting frontal and mesethmoid. Frontal elongated, narrow, with width slightly larger than half of entire length; anterior projection short, size smaller than nasal length. Frontal fontanel large, slender; posterior tip extension slightly entering anterior margin of parietosupraoccipital. Parieto-supraoccipital wide, posterior process long and contacting nuchal plate; region of contact between posterior process and nuchal plate covered by thick layer of skin. Two laminar infraorbitals with minute odontodes; infraorbital 1 large, ventral laminar expansion very reduced; anterior portion with poorly developed expansion (Fig. 2); infraorbital 2 small, thickened; with posterior laminar expansion well developed; posteroventral margin contacting posterodorsal ridge of hyomandibula, dorsal tip contacting sphenotic and compound pterotic (Fig. 3). Posterodorsal ridge of hyomandibula close to its articulation with opercle conspicuously slender; exposed, very reduced and bearing small odontodes; dorsal ridge of hyomandibula between compound pterotic and opercle covered by posterodorsal laminar expansion of infraorbital 2. Interopercle almost entirely exposed, somewhat triangular, anterior projection well developed. Preopercle slender, elongated, with minute sparse odontodes on external surface. Opercle dorsoventrally elongated, width equal or smaller than length; free margin slightly convex, without serrations and covered by small odontodes. Anteroventral portion of cleithrum and posterolateral portion of scapulocoracoid exposed. Anteroventral and posteroventral suture between cleithrum and scapulocoracoid exposed; moderately developed odontodes sparse on exposed areas. Vertebral count 22(2); ribs 7(2), first pair conspicuously larger; complex vertebra slender in shape. Neural and haemal spines with laminar expansions on anterior margin of proximal region; expanded in distal tips. Four branchiostegals rays decreasing in size posteriorly. Hypobranchial 2 somewhat triangular, tip ossified and directed towards anterior portion, posterior margin cartilaginous; ossified portion well developed, about twice size of cartilaginous portion. Five ceratobranchials with expansions increasing posteriorly; ceratobranchial 1 with small process on anterior margin of mesial portion; ceratobranchial 3 notched on posterolateral margin; ceratobranchial 5 toothed on posterodorsal surface, 26 to 29(2) teeth aligned in one row. Four epibranchials with similar size; epibranchial 2 slightly larger than others, with small pointed process on laminar expansion of posterior margin; epibranchial 3 with triangular uncinate process on laminar expansion of posterior margin. Two wide pharyngobranchials (3 and 4), pharyngobranchial 3 with large triangular laminar expansion on posterior margin. Upper tooth plate oval; 26 to 31(2) teeth aligned in two rows on posteroventral surface. Lateral-line canal entering neurocranium through compound pterotic, splitting into two branches before entering sphenotic: pterotic, with single pore, and preoperculo mandibular, with two pores. Sensory canal continuing through compound pterotic, entering sphenotic as temporal canal, which splits into two branches:one branch giving rise to infraorbital canal, other branch entering frontal through supraorbital canal, both with a single pore. Supraorbital canal not branched, running through nasal bone. Epiphyseal pore opening at supraorbital main canal, slightly directed towards frontal fontanel. Nasal canal with two pores. Infraorbital canal running through entire second infraorbital, extending to infraorbital 1 and opening into two pores. Preoperculo mandibular branch giving rise to preoperculo-mandibular canal, which runs through entire preopercle with three openings, leading to pores 3, 4, and 5, respectively. Dorsal fin triangular, located just posterior to second dorsolateral body plate. Dorsal-fin rays II,7(2), II,8(18), posterior margin of dorsal-fin spine with 12 to 13 serrations directed towards dorsal-fin spine tip; serrations absent only on proximal region of posterior margin. Nuchal plate relatively large; exposed, with minute odontodes; spinelet short; spine relatively long, adpressed distal tip surpassing last dorsal-fin branched ray origin; anterior margin with small odontodes. Pectoral fin triangular, its origin just posterior to gill opening. Pectoral-fin rays I,7(14), I,8(6); posterior margin of pectoral spine with 14 to 17 well-developed conical serrations along its entire length; serrations directed towards pectoral-spine origin (Fig. 4). Pelvic fin oblong, located just below second ventrolateral body plate, and at vertical through second branched dorsal-fin ray. Pelvic-fin rays i,5. Adipose fin roughly triangular, separated from base of last dorsal-fin ray by typically seven dorsolateral body plates. Anal fin triangular, located just posterior to 12 th ventrolateral body plates, and at vertical through anterior margin of adiposefin spine. Anal-fin rays ii,5(1), ii,6(19). Caudal-fin rays i,12,i, generally four dorsal and ventral procurrent rays; bilobed, lobes with similar size. Two laterosensory canals on trunk; first ossicle tubular and second ossicle laminar. Body plates with minute odontodes scattered over exposed area, a conspicuous line of odontodes confined on posterior margins; dorsolateral body plates 23(2), 24(16), 25(2); ventrolateral body plates 21(17), 22(3); dorsolateral body plates along dorsal fin base 6; dorsolateral body plates between adipose and caudal fin 6(2), 7(8), 8(10); preadipose platelets 1(14), 2(6); small platelets covering base of caudal-fin rays; small platelets disposed dorsally and ventrally between junctions of lateral plates on posterior portion of caudal peduncle. Dorsal portion of snout, lateral ethmoid region, and upper lip region covered with small platelets. Ventral surface of trunk without platelets. Color in alcohol. Ground color of the body yellowish, with top of the head and snout dark brown. Top of the head and snout, infraorbitals, opercle, preopercle, interopercle, compound pterotic, cleithrum, upper lip, maxillary and outer mental barbels covered by dark brown chromatophores. Dorso- and ventrolateral body plates with vertically elongated or irregular brown blotches anteriorly to adipose fin; lateral portion of caudal peduncle almost entirely blackened. Dorsal fin with diffuse black spots on dorsal-fin rays, generally restricted to the upper half of the dorsal fin. Pectoral, pelvic and anal fins with black chromatophores on rays. Adipose fin with anterior portion hyaline; posterior portion darkened. Caudal fin with four to nine transversal black bars (Fig. 2). Geographic distribution. Corydoras guapore is only known from the upper rio Guapor�� basin in Brazil (Fig. 6). Color in life. Similar to preserved specimens but with ground color of the body rosy. Top of the head and snout, infraorbitals, opercle, preopercle, interopercle, compound pterotic and cleithrum with irregular striated brownish dots. Fins whitish; black spots on dorsal-fin rays more evident. Body covered by a yellowish green iridescent coloration (Fig. 5). Sexual dimorphism. Additionally to the presence of lanceolate genital papilla in males, which is common to all Corydoradinae (see Nijssen & Isbr��cker, 1980; Britto, 2003), the males are generally smaller than females (Fig. 5b). Ecological notes. Corydoras guapore is a freeswimming species, which occupies the middle of the water column in a small group when they feel safe (Fig. 5a), similar to the observed in C. hastatus. They form small breeding groups of up to 20 specimens associated to aquatic macrophytes, like Eichhornia. Unlike most of the Corydoras species which generally inhabit streams or the main channel of rivers, C. guapore is generally captured in lentic habitats as ponds and lakes (Hans- Georg Evers, pers. comm.). The specimens examined herein were captured close to the banks of the rio Guapor��, in Mato Grosso State (Cl��udio Oliveira and Markos Alexandrou, pers. comm.) (Fig. 7). Material examined. All from Brazil, Mato Grosso State, Municipality of Vila Bela da Sant��ssima Trindade, rio Guapor��, rio Madeira basin. LBP 10089, 80, 24.4-30.8 mm SL. ZUFMS-PIS 4000, 5, 26.9-33.6 mm SL, 2 c&s, 28.8- 29.2 mm SL. Conservation status. Despite the fact that the species is known only from its type-locality (rio Guapor��) it is probably widespread in the surroundings and no imminent threat is suspected, therefore, according to the International Union for Conservation of Nature (IUCN) categories and criteria (IUCN Standards and Petitions Subcommittee, 2014), Corydoras guapore can be classified as Least Concern (LC)., Published as part of Tencatt, Luiz Fernando Caserta & Pavanelli, Carla Simone, 2015, Redescription of Corydoras guapore Knaack, 1961 (Siluriformes: Callichthyidae), a midwater Corydoradinae species from the rio Guapor�� basin, pp. 287-296 in Neotropical Ichthyology 13 (2) on pages 288-293, DOI: 10.1590/1982-0224-20150018, http://zenodo.org/record/4551329, {"references":["Knaack, J. 1961. Ein neuer Panzerwels aus Brasilien (Corydoras guapore) (Pisces, Teleostei, Callichthyidae). Sitzungsberichte der Gesellschaft Naturforschender Freunde zu Berlin (n. f.), 1: 135 - 138.","Internation Union for Conservation of Nature (IUCN) Standards and Petitions Subcommittee. 2014. Guidelines for using the IUCN Red List Categories and Criteria. Version 11. Prepared by the Standards and Petitions Subcommittee. Available from: http: // www. iucnredlist. org / documents / RedListGuidelines. pdf (Date of access - 19 May 2015)."]}

Located in the Pantanal of Miranda-Abobral, the Baía da Medalha is the largest pond close to the Base de Estudos do Pantanal of the Universidade Federal de Mato Grosso do Sul. The Baía da Medalha has been a study site for several didactic and scientific projects for years. Nevertheless, its fish fauna has never been inventoried. Based on data collected from the beginning of the 1990s up to 2011, we provide a list of fish species from the Baía da Medalha. A total of 97 species were recorded, corresponding to about 40% of the species stated for the Pantanal. Characiformes and Siluriformes were the most species-rich orders, being Characidae and Cichlidae the families with the highest number of species. Regional seasonal flood dynamics and the abundance of aquatic macrophytes may be associated with this high diversity. The representative richness found in this lagoon highlights the importance of such taxonomic surveys to preserve the diversity of aquatic habitats within the Pantanal ecosystem. Resumo Localizada no Pantanal do Miranda-Abobral, a Baía da Medalha é a maior e mais próxima lagoa da Base de Estudos do Pantanal da Universidade Federal de Mato Grosso do Sul. A Baía da Medalha tem sido área de estudo de diversos projetos didáticos e científicos há anos, entretanto, nenhum inventário sobre sua ictiofauna foi realizado. Aqui é apresentada uma lista de espécies de peixes da Baía da Medalha baseado em dados de coletas do começo da década de 90 até 2011. Um total de 97 espécies foi registrado, correspondendo è cerca de 40% do total de espécies registradas para o Pantanal. Characiformes e Siluriformes foram as ordens mais ricas em espécies, sendo Characidae e Cichlidae as famílias com maior número de espécies. Dinâmicas de inundação sazonal e a abundância de macrófitas aquáticas podem ser associadas a esta alta diversidade. A representativa riqueza encontrada nesta lagoa ressalta a importância de levantamentos taxonômicos a fim de preservar a diversidade dos habitats aquáticos do dentro do ecossistema do Pantanal.

Corydoras paleatus is a widely distributed species, occurring in the lower rio Paraná basin, south region of Brazil and Argentina, and coastal rivers in Uruguay and Brazil. The type-locality of this species is uncertain, as mentioned by Jenyns in the original description "the exact locality in South America in wich Mr. Darwin obtained this species is uncertain as the specimens have lost their attached labels", by this reason any exemplar with similar color pattern mentioned in the Jenyns' description is identified as Corydoras paleatus. However morphometric and genetical evidences shows that the populations attributed to C. paleatus may represent a complex of species. A comprehensive review analyzing specimens attributed to that species from several localities was carried out, considering available specimens of most Brazilian collections, additionally some collections from Argentina, Sweden and Uruguay. The analysis of the gathered material allowed the recognition of C. paleatus proper and four new species formerly identified as C. paleatus. Corydoras paleatus occurs below Itaipu dam, in the lower rio Paraná and rio Uruguay basin, and also in coastal basins of southern Brazil and Uruguay. Corydoras sp. A has wide geographical distribution, occurring in the upper and lower rio Paraná basin, rio Uruguay and coastal basins of southern Brazil and Uruguay. Corydoras sp. B is known to the lower rio Iguaçu basin, Corydoras sp. C to rio Pelotas basin and Corydoras sp. D from rio Bermejo basin. Coloration pattern, osteological features, proportions and counts are used to diagnose those species. A key for identification is provided, besides a map of geographic distribution and pictures of all species. Corydoras paleatus é uma espécie amplamente distribuída, ocorrendo na bacia do baixo rio Paraná, região sul do Brasil e Argentina, e rios costeiros do Uruguai e Brasil. A localidade-tipo dessa espécie é incerta, como mencionado por Jenyns na descrição original "a localidade exata na América do Sul a qual o Sr. Darwin obteve essa espécie é incerta já que os espécimes perderam seus rótulos anexados", por essa razão, qualquer exemplar com padrão de coloração similar ao mencionado na descrição de Jenyns, é identificado como Corydoras paleatus. Todavia, evidências morfométricas e genéticas mostram que as populações atribuídas a C. paleatus podem representar um complexo de espécies. Uma revisão abrangente, analisando material atribuído a essa espécie de diversas localidades foi conduzida, considerando espécimes disponíveis de várias coleções brasileiras, adicionalmente algumas coleções da Argentina, Suécia e Uruguai. A análise do material reunido permitiu o reconhecimento de C. paleatus propriamente e quatro novas espécies anteriormente identificadas como C. paleatus. Corydoras paleatus ocorre abaixo da barragem de Itaipu, na bacia do baixo rio Paraná, rio Uruguai e também nas bacias costeiras da região sul do Brasil e Uruguai. Corydoras sp. A possui uma vasta distribuição geográfica, ocorrendo nas bacias do alto e baixo rio Paraná, rio Uruguai e bacias costeiras da região sul do Brasil e Uruguai. Corydoras sp. B é conhecida da bacia do baixo rio Iguaçu, Corydoras sp. C da bacia do rio Pelotas e Corydoras sp. D da bacia do rio Bermejo. Padrão de coloração, caracteres osteológicos, proporções e contagens foram usados para diagnosticar essas espécies. Uma chave de identificação é fornecida, além de um mapa de distribuição geográfica e figuras de todas as espécies. 60 f