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Lepadella yangambi n. sp. Figures 8 a–d, I-8 Type locality. Yangambi primary forest, DR Congo, 11 June 2012 (Y27). Material examined. Holotype: One female specimen in permanent slide, deposited in RBINS (RIR.321); Paratypes: seven permanent slides containing one female specimen each, and three permanent slides containing two female specimens each, deposited in RBINS (RIR.322 to RIR.331); two permanent slides containing three female specimens each, CSB-UK; one permanent slide containing five female specimens, deposited in SHNU; numerous additional specimens in the sample from the type locality. Differential diagnosis. Lepadella yangambi n. sp. can be confused with Lepadella bidentata Voronkov, 1913 and L. dactyliseta (Stenroos, 1898). While the posterior spines are clearly set off from the lorica in L. yangambi n. sp. and formed as extensions of the lorica in the other taxa, the deeply invaginated dorsal head aperture margin and blunt sublongitudinal ridges on the dorsal lorica are unique to L. yangambi n. sp. Finally, the new species has a much higher lorica than L. biloba Hauer, 1958. Differential diagnosis. Parthenogenetic female (male unknown): Lorica elongate, elliptical, width about two thirds of length. Ventral lorica relatively flat, dorsally strongly domed, lorica less than twice as wide as high. Dorsal lorica ornamented by a pair of sublongitudinal, sublateral, blunt ridges starting near the head aperture, and running to near the openings of the dorsal antennas. Head aperture ventrally a deep U- or V-shaped sinus, dorsally semi-circular in anterior view, broadly U-shaped in ventral view, no collar. Lateral edges of lorica smooth, evenly curved, posterior edge convex. Apertures to the lateral antennas situated at the level of the first foot pseudosegment in contracted specimens, arranged symmetrically about medially from the longitudinal symmetry axis to the lateral margins of the lorica. Foot aperture elongate, broadest medially, lateral margins converging to both anteriorly and posteriorly. Foot with three distinct pseudosegments, the distal one slightly longer than the second, bearing a dorsal sensory groove near its basis. Two equal toes, these evenly tapering to distally. Measurements (n=10). Lorica length: 75–82 (77), lorica width: 58–75 (61), head aperture width: 23–28 (25), depth dorsally: 5–12 (7), ventrally: 15–20 (18), foot aperture width: 12–18 (14), length: 18–19 (18), toe length: 17–21 (19). Etymology. This specific name is a noun in apposition, derived from the name of its type locality, Yangambi primary forest., Published as part of Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers, pp. 371-387 in Zootaxa 4731 (3) on page 378, DOI: 10.11646/zootaxa.4731.3.6, http://zenodo.org/record/3653632, {"references":["Voronkov, N. V. (1913) K faunje kolovratok Rossii. Trudy Gidrobiologiceskoj stancii na Glubokom ozerje, 5, 90 - 108.","Stenroos, K. E. (1898) Das Thierleben im Nurmijarvi-See. Acta Societatis pro Fauna et Flora Fennica, 17, 1 - 259.","Hauer, J. (1958) Radertiere aus dem Sumpfe \" Grosse Seewiese \" bei Kist. Nachrichten des naturwissenschaftlichen Museums der Stadt Aschaffenburg, 60, 1 - 52."]}

Lepadella wilungulai n. sp Figures 9 a–c, I-6 Type locality. Lulu River near Basoko, DR Congo 21 May 2010 (KM27). Material examined. Holotype: one female specimen in permanent slide, deposited in RBINS (RIR.320). Differential diagnosis. The three exceptionally well-developed dorsal carinae of L. wilungulai n. sp. distinguish the species unequivocally from all congeners. The only species with which the animal might be compared is L. donneri Koste, 1972 which has very similar lateral carinae but which lacks the dorsal carina and which has a more rounded lorica. A third, unnamed Neotropical relative recorded by Koste & Böttger (1992) as “ Lepadella quinquecostata nov. forma?” and by José de Paggi (2001) as L. quinquecostata also has extraordinarily developed carinae, but this animal has five, less developed and differently situated carinae, is larger, and has a differently shaped lorica. Differential diagnosis. Parthenogenetic female (male unknown): Lorica elongate, roughly egg-shaped, width about two thirds of length. Ventral lorica nearly flat, dorsal domed, lorica about twice as wide as high. Head aperture ventrally a deep U-shaped sinus, dorsally semi-circular in anterior view, a broad U-shaped sinus in ventral view, with collar. Dorsal lorica with three longitudinal carinae: one median, and a pair of lateral carinas running from the anterior tips of the lorica to just anterior of the apertures to the dorsal antennas. Dorsal carina extremely high and narrow. Lateral edges of lorica smooth, evenly curved, posterior edge with a minute convex projection as extension of the dorsal carina. Apertures to the lateral antennas situated at the level of the anterior margin of the foot aperture, arranged symmetrically about medially from the middorsal carina to the lateral margin of the lorica. Foot aperture elongate, lateral margins nearly parallel. Foot with three distinct pseudosegments, the distal one about thrice as long as the second, bearing a dorsal sensory groove near its basis. A pair of equal-sized toes present, these almost parallel-sided proximally, more strongly tapering from about midway to distally. Measurements (n=1). Lorica length: 117, width: 86; Head aperture width: 24, head aperture depth dorsally: 8, ventrally: 19, Foot aperture width: 16, length: 30, toe length: 33. Etymology. The specific name is as a noun in the genitive case, dedicated to Dr Father Cosma Wilungula, Executive director of the Institut Congolais pour la Conservation de la Nature, in recognition of his contribution to nature conservation in the Democratic Republic of Congo. Remark. We acknowledge that describing and naming a new rotifer species based on a single specimen is a practice frowned upon, for good reasons, by numerous authorities including, e.g., Ruttner-Kolisko (1989) and Koste & Shiel (1989). However, the unique features of the holotype, the outstandingly easy diagnosis and the potential biogeographical relevance of the animal convince us to exceptionally proceed with the description and establishment of a new name for the single specimen discovered., Published as part of Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers, pp. 371-387 in Zootaxa 4731 (3) on page 377, DOI: 10.11646/zootaxa.4731.3.6, http://zenodo.org/record/3653632, {"references":["Koste, W. (1972) Rotatorien aus Gewassern Amazoniens. Amazoniana, 3, 258 - 505.","Koste, W. & Bottger, K. (1992) Rotatorien aus Gewassern Ecuadors II. Amazoniana, 12, 263 - 303.","Jose De Paggi, S. (2001) Diversity of Rotifera (Monogononta) in wetlands of Rio Pilcomayo National Park, Ramsar Site (Formosa, Argentina). Hydrobiologia, 462, 25 - 34. https: // doi. org / 10.1023 / A: 1013157914860","Ruttner-Kolisko, A. (1989) Problems in taxonomy of rotifers, exemplified by the Filinia longiseta-terminalis complex. Hydrobiologia, 186 / 187, 291 - 298. https: // doi. org / 10.1007 / BF 00048924"]}

Squatinella curviseta n. sp. Figures 1 a–b, I-3 Type locality. Lohulu River near Bomane, DR Congo 24 May 2010 (KM49). Material examined. Holotype: One female specimen in permanent slide, deposited in RBINS (RIR.332); Paratypes: five permanent slides containing one female specimen each, deposited in RBINS (RIR.333 to RIR.338); one permanent slide containing seven female specimens, deposited in CSB-UK. Differential diagnosis. This new species is close to S. variegata, as it shares with it a foot made up of two basal foot pseudosegments and a third element consisting of the fused third foot pseudosegment and the toes. The two differ by the rather rigid dorsal spine, which is variable in length but always straight in S. variegata, and relatively short and weakly but clearly and consistently S-shaped in S. curviseta n. sp. This peculiar spine shape may be adaptive: in swimming specimens the spine is bent posteriad, along the longitudinal axis of the body; in S. curviseta n. sp. this S-shaped spine will fit snugly over the body and foot, possibly resulting in reduced drag when the animal glides over a surface. Differential diagnosis. Parthenogenetic female (male unknown): body elongate, separated in a head, trunk, and foot region, lorica relatively soft but body shape rather constant. Head dorso-ventrally flattened, with a semi-circular head shield covering the homogeneous corona; lateral projections of the posterior corona region present. Head and trunk separated by a weakly constricted neck. Trunk rather plump, ventrally bulbous, dorsally with a middorsal, rigid, weakly S-shaped and terminally blunt spine; this spine movable from erect to dorsally, parallel to the body axis overlaying the foot. Terminal part of the trunk bulging. Foot with two separated foot pseudosegments, the second about twice as long as the first, third foot element more than twice as long as the second foot pseudosegment, bearing a sensory groove dorsally near its basis. Terminal foot element almost parallel-sided in the basal two thirds, then tapering to a point, distally with a short median fissure. Measurements (n=10). Total length (including foot): 219–257 (238), height: 94–117 (104), second foot pseudosegment: 19–27 (22), fused third segment and toes: 30–46 (37), dorsal spine: 146–190 (161), ratio spine:body length: 0.66–0.92 (0.83). Etymology. The specific name is an adjective, and refers to the species’ unique curved dorsal spine., Published as part of Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers, pp. 371-387 in Zootaxa 4731 (3) on pages 380-382, DOI: 10.11646/zootaxa.4731.3.6, http://zenodo.org/record/3653632

Lepadella weijiai n. sp. Figures 7 a–c, I-7 Type locality. Yangambi primary forest, DR Congo, 11 June 2012 (Y27); a few specimens from Lohulu River near Bomane, DR Congo 24 May 2010 (KM49). Numerous additional specimens in the sample from the type locality. Material examined. Holotype: one female specimen in permanent slide, deposited in RBINS (RIR. 312); Paratypes: seven permanent slides containing one female specimen each, deposited in RBINS (RIR.313 to RIR.319); three permanent slides containing two female specimens each, deposited in CSB-UK. Differential diagnosis. The high and broad dorsal longitudinal dome of the lorica in L. weijiai n. sp. is unique amongst Lepadella species and it is therefore hardly likely that the species would be mistaken for any congener. Nevertheless, confusion could be possible with L. rhomboides (Gosse, 1886) in Hudson & Gosse 1886), but the latter has a more elongate lorica, its dorsal dome is triangular in cross-section, and it has an elongate terminal foot pseudosegment. Also L. pyriformis Myers, 1938 and L. whitfordi Ahlstrom, 1938 have a broad dorsal longitudinal dome, but in these species this dome is either rounded in cross-section (L. pyriformis) or has four broad, longitudinal ridges (L. whitfordi), and the toes are distinctly longer. Description. Parthenogenetic female (male unknown): Lorica elongate, elliptical, widest medially, less than twice as wide as high. Ventral lorica slightly convex, dorsally with a strongly developed longitudinal dome. Dorsal dome starting anteriorly at the head aperture, broadening to medially then converging to subterminally. Lateral parts of dorsal dome starting off ventrally concave, dorsally with relatively sharp lateral, and a rounded middorsal fold. Head aperture ventrally a deep V-shaped sinus, dorsally semi-circular in anterior view, broadly U-shaped in ventral view, with stippled collar. Lateral edges of lorica smooth, evenly curved, posterior edge pronouncedly convex. Apertures to the lateral antennas situated near the posterior end of the lateral concavities, slightly posterior to the level of the anterior margin of the foot aperture. Foot aperture elongate, broadest medially, lateral margins converging to both anteriorly and posteriorly. Foot with three distinct pseudosegments, the distal one slightly longer than the second, bearing a dorsal sensory groove near its basis. Two equal toes, these evenly tapering to distally. Measurements (n=10). Lorica length: 77–92 (88), width: 74–78 (76), head aperture width: 23–30 (26), depth dorsally: 4–15 (11), depth ventrally: 20–25 (22), Foot aperture width: 13–18 (16), length: 18–23(22), toe length: 15–23 (19). Etymology. The specific name is as a noun in the genitive case, formed after the name of the late Professor Weijia Yuan of Shanghai Normal University, in recognition of a life dedicated to scientific research and teaching., Published as part of Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers, pp. 371-387 in Zootaxa 4731 (3) on pages 376-377, DOI: 10.11646/zootaxa.4731.3.6, http://zenodo.org/record/3653632, {"references":["Hudson, C. T. & Gosse, P. H. (1886). The Rotifera; or wheel-animalcules, both British and foreign. Vol. 1 & 2. Longhans, Green & Co., London, 128 pp., 15 pls. & 144 pp., A-D + 16 - 30 pls.","Myers, F. J. (1938) New species of Rotifera from the collection of the American Museum of Natural History. American Museum Novitates, 1011, 1 - 17.","Ahlstrom, E. H. (1938) Plankton Rotatoria from North Carolina. Journal of the Elisha Mitchell Scientific Society, 54, 88 - 110."]}

Lepadella sp. near acuminata sensu Baribwegure & Segers (2001) In addition to the Lepadella described above, we found numerous specimens of the species referred to as Lepadella sp. near acuminata by Baribwegure & Segers (2001) from Burundi. The same animal was recorded before as L. cryphaea Harring, 1916 by Segers et al. (1993a) and, in contrast to the second author’s previous understanding, is not conspecific with L. elongata Koste, 1992 (see Segers & Dumont 1995), considering the quite different dorsal lorica patterns of both. We refrain from treating the taxon in more detail until more information becomes available. Measurements (n=10). Lorica length: 90–95 (93), width: 58–64 (62), Head aperture width: 22–25 (23), Head aperture dorsal depth: 10–13 (12), Head aperture ventral depth: 17–19 (18), Foot aperture width: 14–16 (15), Foot aperture length: 26–28 (26), Toe length: 18–23 (21)., Published as part of Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers, pp. 371-387 in Zootaxa 4731 (3) on page 378, DOI: 10.11646/zootaxa.4731.3.6, http://zenodo.org/record/3653632, {"references":["Baribwegure, D. & Segers, H. (2001) Rotifera from Burundi: the Lepadellidae (Rotifera: Monogononta). Hydrobiologia, 446 / 447, 247 - 254. https: // doi. org / 10.1023 / A: 1017576028621","Harring, H. K. (1916) A revision of the rotatorian genera Lepadella and Lophocharis with descriptions of five new species. Proceedings of the United States National Museum, 51, 527 - 568. https: // doi. org / 10.5479 / si. 00963801.51 - 2164.527","Segers, H., Nwadiaro, C. S. & Dumont, H. J. (1993 a) Rotifera of some lakes in the floodplain of the river Niger (Imo State: Nigeria). II. Faunal composition and diversity. Hydrobiologia, 250, 63 - 71. https: // doi. org / 10.1007 / BF 00007495","Koste, W. & Bottger, K. (1992) Rotatorien aus Gewassern Ecuadors II. Amazoniana, 12, 263 - 303.","Segers, H. & Dumont, H. J. (1995) 102 + rotifer species (Rotifera: Monogononta) in Broa reservoir (SP., Brazil), on 26 August 1994, with the description of three new species. Hydrobiologia, 316, 183 - 197. https: // doi. org / 10.1007 / BF 00017436"]}

Luo, Yongting, Segers, Hendrik (2020): Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers. Zootaxa 4731 (3): 371-387, DOI: https://doi.org/10.11646/zootaxa.4731.3.6

Lepadella hanneloreae n. sp. Figures 5 a–c, I-4 Type locality. Lohulu River near Bomane, DR Congo 24 May 2010 (KM49, KM48); a few specimens from Yangambi primary forest, DR Congo, 11 June 2012 (Y25). Numerous additional specimens in the samples from the type locality. Material examined. Holotype: female specimen in permanent slide, deposited in RBINS (RIR.292); Paratypes: seven permanent slides containing one female specimen each, deposited in RBINS; five permanent slides containing two female specimens each, deposited in RBINS (RIR.293 to RIR.304), one permanent slide containing three female specimens, deposited in CSB-UK. Differential diagnosis. Lepadella hanneloreae n. sp. is strikingly similar to L. amazonica Segers, 1993 (in Segers et al. 1993b). The two differ by the dorsal carinae on the lorica: in L. hanneloreae n. sp. there is one pair of middorsal and one pair of lateral carinae, whereas in L. amazonica there are two pairs of closely adjacent lateral carinae. Furthermore, the new species is probably related to L. berzinsi Segers, 1993, but the latter has three pairs of more pronounced carinae situated at regular distances from each other. Description. Parthenogenetic female (male unknown): Lorica elongate, roughly egg-shaped, width about two thirds of length. Ventral lorica flat, dorsal domed, lorica about twice as wide as high. Head aperture ventrally a deep V-shaped sinus, dorsally semi-circular in anterior view, straight in ventral view, with stippled collar. Dorsal lorica with two pairs of longitudinal carinae: one median pair, fused in the distal third of the lorica, one lateral pair running from behind the collar to approximately level of the apertures to the dorsal antennas. Lateral edges of lorica smooth, evenly curved, posterior edge nearly straight or with a shallow median notch. Apertures to the lateral antennas situated at the level of the anterior margin of the foot aperture, arranged symmetrically about medially from the fused median carinas to the lateral margin of the lorica. Foot aperture elongate, lateral margins nearly parallel. Foot with three distinct pseudosegments, the distal one about twice as long as the second, bearing a dorsal sensory groove near its basis. Two equal toes, these evenly tapering to distally. Measurements (n=10). Lorica length: 91–106 (100), width: 60–70 (67); head aperture width: 23–37 (29), head aperture depth dorsally: 7–14 (10), ventrally: 19–24 (21); foot aperture width: 18–20 (19), length: 23–33 (27), toe length: 22–29 (25). Etymology. The specific name is as a noun in the genitive case, after Mrs Hannelore Segers, daughter of the second author of this paper., Published as part of Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers, pp. 371-387 in Zootaxa 4731 (3) on pages 374-376, DOI: 10.11646/zootaxa.4731.3.6, http://zenodo.org/record/3653632, {"references":["Segers, H., dos Santos-Silva, E. N. & de Oliveira-Neto, A. L. (1993 b) New and rare species of Lecane and Lepadella (Rotifera: Lecanidae; Colurellidae) from Brazil. Belgian Journal of Zoology, 123, 113 - 121."]}

Lepadella jingruae n. sp. Figures 6 a–c, I-5 Type locality. Lohulu River near Bomane, DR Congo 24 May 2010 (KM48, KM49). Material examined. Holotype: one female specimen in permanent slide, deposited in RBINS (RIR.305); Paratypes: six permanent slides containing one female specimen each, deposited in RBINS (RIR.306 to RIR.311), one permanent slides containing one female specimen and one permanent slide containing two female specimens in CSB-UK; one permanent slide containing two female specimens, deposited in SHNU. Differential diagnosis. The relatively flat lorica of L. jingruae n. sp. places the species in the vicinity of L. ovalis (Müller, 1786) and L. eurysterna Myers, 1942. The new species is diagnosed from both by the remarkable protruding projections laterally of the head aperture, and further from L. ovalis by its smaller size and posteriorly rounded lorica (relatively large and with a sharply set-of posterior concavity in L. ovalis). Lepadella jingruae n. sp. can easily be distinguished from species of the L. patella— complex, including the similarly rounded L. discoidea Segers, 1993 by its flat lorica and the protruding lateral projections of the head aperture. Differential diagnosis. Parthenogenetic female (male unknown): Lorica rounded, about as wide as long. Ventral lorica flat, dorsally with a central dome, lateral parts strongly flattened, lorica about thrice as wide as high. Head aperture ventrally a deep V-shaped sinus, dorsally semi-circular in anterior view, broadly U-shaped in ventral view, with weak collar. Anterior of lorica protruding into a pair of well-developed, sharp projections. Lateral margins of lorica smooth, evenly curved, posterior edge convex. Dorsal lorica smooth, without markings. Apertures to the lateral antennas situated slightly posterior the level of the anterior margin of the foot aperture, arranged symmetrically about medially from median axis to the lateral margin of the lorica. Foot aperture elongate, lateral margins diverging to posteriorly. Foot with three distinct pseudosegments, the distal one about twice as long as the second, bearing a dorsal sensory groove near its basis. A pair of equal-sized toes present, these almost parallel-sided basally, more strongly tapering from about midway to distally. Measurements (n=10). Lorica length: 100–110 (106), width: 90–101 (93); head aperture width: 25–31 (28), depth dorsally: 15–21 (18), depth ventrally: 24–28 (25), foot aperture width: 15–19 (18), length: 26–31 (28), toe length: 26–29 (29). Etymology. The specific name is as a noun in the genitive case, after Miss Jingru Zhu, daughter of the first author of this paper., Published as part of Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers, pp. 371-387 in Zootaxa 4731 (3) on page 376, DOI: 10.11646/zootaxa.4731.3.6, http://zenodo.org/record/3653632, {"references":["Muller, O. F. (1786) Animalcula infusoria fluviatilia et marina, quae detexit, systematice descripsit et ad vivum delineari curavit. Typis Nicolai Molleri, Havniae, 367 pp., 1 - 50 pls. https: // doi. org / 10.5962 / bhl. title. 47041","Myers, F. J. (1942) The Rotatorian Fauna of the Pocono Plateau and Environs. Proceedings of the Academy of Natural Sciences of Philadelphia, 94, 251 - 285."]}

Colurella asymmetrica n. sp. Figures 3 a–c, I-1 Type locality. Most specimens are from a pond in Yangambi primary forest, DR Congo, 11 June 2012 (Sample Number: Y27); a single specimen from Lohulu River near Bomane, DR Congo, 24 May 2010 (KM49). Material examined. Holotype: one female specimen in permanent slide, deposited in RBINS (RIR.287); Paratypes: four permanent slides containing one female specimen each, deposited in RBINS (RIR. 288 to RIR.291), four permanent slides containing one female specimen each, deposited in CSB-UK. Differential diagnosis. The taxon belongs to Colurella uncinata— group on account of its relatively short and high lorica, and short toes, and appears closest to C. uncinata bicuspidata (Ehrenberg, 1830) (Figure 4). The animal is, however, readily distinguished by the asymmetrical posterior lorica and by the shape of the single caudal spine, which is not merely an extension of the ventral lorica margin, but is reinforced by a short ridge. By having an asymmetrical caudal spine the animal reminds of C. sinistra Carlin, 1939 and C. ovalis Wei et al., 2019, but the latter species are larger, and are easily distinguished by their differently shaped lorica and caudal spine shape. The shape of the caudal spine in C. asymmetrica n. sp. is somewhat similar to that of C. collaris Wulfert, 1965, but this species has a pronouncedly projecting and stippled head aperture margin. Differential diagnosis. Parthenogenetic female (male unknown): Lorica relatively high (length: height Measurements (n=6). Lorica length: 75–80 (77); lorica width: 47–50 (49), lorica height: 48–50 (49); right caudal spine: 7–9 (7); left caudal spine: 2–4 (3); head aperture width: 4–11 (7); depth dorsally: 5–10 (7); depth ventrally: 26–30 (29); Foot aperture width: 11–13 (12); length: 21–26 (24); toe length: 12–18 (16). Etymology. The specific name is an adjective, referring to the species’ most remarkable diagnostic feature, the asymmetrical caudal spines of the lorica., Published as part of Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers, pp. 371-387 in Zootaxa 4731 (3) on page 374, DOI: 10.11646/zootaxa.4731.3.6, http://zenodo.org/record/3653632, {"references":["Carlin, B, (1939) Uber die Rotatorien einiger Seen bei Aneboda. Meddelanden Lunds Universitets Limnologiska Institution, 2, 1 - 68.","Wei N., Jersabek, C. D., Xu, R. & Yang, Y. (2019) New species and records of Colurella (Rotifera: Lepadellidae) from South China, with a key to Chinese Colurella. Zootaxa, 4586 (3), 475 - 490. https: // doi. org / 10.11646 / zootaxa. 4586.3.5","Wulfert, K. (1965) Radertiere aus einigern afrikanishen Gewassern. Limnologica, Berlin, 3 (3), 347 - 366."]}

Squatinella longipila n. sp. Figures 2 a–c, I-2 Type locality. Yangambi primary forest, DR Congo, 11 June 2012 (Y27); a single specimen from Lohulu River near Bomane, DR Congo 24 May 2010 (KM28). Material examined. Holotype: One female specimen in permanent slide, deposited in RBINS (RIR.339); Paratypes: three permanent slides containing one female specimen each, deposited in RBINS (RIR.340 to RIR.342); two permanent slides containing one female specimen each, CSB-UK; one paratype in SHNU. Differential diagnosis. This relatively small Squatinella appears related to S. longispinata, by having a foot with three separate foot pseudosegments and separate toes. It differs from that species by lacking an additional spine overlaying the toes, and by its extremely long dorsal spine, reaching more than twice the total body length (including foot). Differential diagnosis. Parthenogenetic female (male unknown): Body elongated, separated in a head, trunk, and foot region, lorica relatively soft but body shape rather constant. Head bearing a semi-circular head shield covering the homogeneous corona; lateral projections of the posterior corona region present, set-off from trunk by a weakly constricted neck. Trunk elongated, ventrally relatively flat, with a transverse fold in the distal third, dorsally with a middorsal, strongly elongated, almost hair-like and terminally pointed spine; this spine with an elongate triangular basis, slightly bent backwards just posterior of the triangular basis, and smoothly curved towards distally. Spine movable from erect to dorsad, parallel to the body axis, overlaying the foot. Vitellarium extending into the basis of the dorsal spine. Terminal part of the trunk falling to the foot. Foot with three separated foot pseudosegments, the second and third about as long and twice as long as the first, third foot pseudosegment bearing a sensory groove dorsally about medially. Two separate, elongate triangular toes. Measurements (n=6). Total length (including foot): 117–130 (122), height: 37–51 (46), foot length: 18–20 (19), toe: 7–9 (7), spine length: 251–303 (278), ratio dorsal spine: body length: 1.94–2.57(2.35) Etymology. The specific name is an adjective, derived from the Latin words “ longus ” (long) and “ pilus ” (a single hair), and refers to the exceptionally elongate dorsal spine that resembles a long, single hair, on the animal’s back. Distribution. In addition to the Congo records, this species may occur in Thailand (S. leydigii after Chittapun et al. (1999: Figure 6)) and Cambodia (S. leydigii after Sor (2011: Figure 18g), from a reservoir in Krang Deisor, Stung Treng province)., Published as part of Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers, pp. 371-387 in Zootaxa 4731 (3) on page 382, DOI: 10.11646/zootaxa.4731.3.6, http://zenodo.org/record/3653632, {"references":["Sor, R. (2011) Comparison of the Rotifer Fauna between Lakes and Reservoirs in the Upper Part of the Cambodian Mekong River Basin. MSc Thesis, Royal University of Phnom Penh, Phnom Penh, 75 pp."]}

Genus Squatinella Bory de St. Vincent, 1924 Our material contains two distinct taxa of Squatinella, both belonging to the S. longispinata-leydigii group as recognized by Koste (1978). The taxonomy of the members of this group is complex and confused due to the rarity of the species and the sometimes contradictory reports. Based on an examination of original sources and the present and other material seen by us, we follow Myers’ (1942), Pourriot’s (1971) and Koste & Shiel’s (1989) conclusion that the group contains at least two well-definable species-level taxa, diagnosed as follows (see Table 3), albeit with changes in synonymy: - Squatinella longispinata (Tatem, 1867) (synonyms: S. leydigii (Zacharias, 1886), S. uniseta (Collins), S. unisetatus (Hudson & Gosse), S. tripus (Hudson)) is here considered to be a relatively small species, with three foot pseudosegments and bearing a minute spine dorsally and terminally on the last foot pseudosegment. Its dorsal lorica spine narrows gradually into a sharp terminal point. Note that neither the (rather superficial) original description of S. longispinata by Tatem (1867) nor that of S. leydigii by Zacharias (1886) mention a foot spine, which may have been overlooked in these early reports. The relevance of the short spines flanking the dorsal spine, as reported for S. longispinata by Pejler (1962) requires further evaluation. - Squatinella variegata (Levander, 1894) (note that Koste’s (1978: T. 58 fig. 2a) reproduction of the foot of S. variegata differs in some minute but important aspects from Levander’s (1894) original figure), a relatively robust species with two short foot pseudosegments and a third terminal element. Based on the peculiar morphology of the terminal foot pseudosegment, we believe that, in S. variegata, the third foot pseudosegment and toes are fused into a single element, while the vestiges of the toes are indicated by a short terminal fissure. This we conclude from the position of the dorsal sensory groove, which is situated basally and dorsally on the third foot pseudosegment in Lepadellidae, and is situated in the same position on the terminal element of the foot in S. variegata and related taxa (see below, Figure 1b). There is no additional toe spine and the dorsal spine is more or less parallel sided along much of its length, and ends in a blunt tip. Relatively large specimens reported by Pourriot (1971) as having a dorsal spine of more than 1.5 times the body length (“f. longiseta ” after Pourriot 1971), may yet be another taxon, in view of the report of them having a different foot structure with two clearly separated toes (Koste, 1978). The two taxa in our material differ in a number of significant aspects from either S. longispinata or S. variegata, prompting us to describe them as new species, as follows., Published as part of Luo, Yongting & Segers, Hendrik, 2020, Eight new Lepadellidae (Rotifera, Monogononta) from the Congo bring to level endemism in Africa's rotifers, pp. 371-387 in Zootaxa 4731 (3) on pages 378-380, DOI: 10.11646/zootaxa.4731.3.6, http://zenodo.org/record/3653632, {"references":["Koste, W. (1978) Rotatoria. Die Radertiere Mitteleuropas. Gebr. Borntraeger, Berlin and Stuttgart, 673 pp., 234 pls.","Pourriot, R. (1971) Deux formes nouvelles du genre Squatinella (Rotiferes) observees en Sologne. Cahiers des naturalistes, Bulletin des Naturalistes Parisiens, 27, 97 - 101.","Tatem, T. G. (1867) New Species of Microscopic Animals. Quarterly Journal of Microscopical Science, 7, 251 - 253.","Zacharias, O. (1886) Ergebnisse einer zoologischen Exkursion in das Glatzer-, Iser- und Riesengebirge. Zeitschrift fur wissenschaftliche Zoologie, 43, 252 - 276.","Pejler, B. (1962) On the taxonomy and ecology of benthic and periphytic Rotatoria. Investigation in northern Swedish Lappland. Zoologiska Bidrag fran Uppsala, 33, 327 - 422.","Levander, K. M. (1894) Materialien zur Kenntniss der Wasserfauna in der Umgebung von Helsingfors, mit besonderer Berucksichtigung der Meeresfauna. II. Rotatoria. Acta Societatis pro Fauna et Flora Fennica, 12, 1 - 72."]}

This study investigates the influence of limnological parameters that are known to influence rotifer species richness and composition in temperate areas on two families of monogonont rotifers in a tropical area. We analysed species richness and diversity of the two families from 133 samples taken from several habitat types in Thailand. Coordinates, elevation, pH, temperature, conductivity, salinity and dissolved oxygen were measured and their effect on rotifers assessed. A total of 60 species in 5 genera was recorded from the two families. Latitude and temperature had an effect on species richness of Brachionidae. None of the variables affected species richness of Lecanidae, except habitat type, albeit not significantly. Habitat type and conductivity had an effect on species composition of the two families, whereas latitude had an effect only on species composition of Lecanidae. Species richness and composition of the two rotifer families are well documented in Thailand and no or only few additional species are expected. The limnological correlates of rotifer diversity seem to be in part comparable to and in part different from those known from temperate areas, suggesting that there may be general trends in rotifer species richness and composition across different latitudes.