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Leptalpheus forceps Williams, 1965 Figures 2���6 Leptalpheus forceps ��� Williams 1965: 192���197, figs. 1, 2; Williams 1984: 101, fig. 69; Anker et al. 2006b: 685, 686, 687; Pachelle et al. 2016: 13, fig. 6C. Leptalpheus cf. forceps ��� Anker 2008: 788, 789, 790, 791, figs. 4, 5, 6A, B; Anker 2011: 6, 7, figs. 3A, B. Leptalpheus aff. forceps ��� Almeida et al. 2012: 15, 17, figs. 5A���D. Material examined. 20 males (CL=4.25 �� 0.61 mm; TL=11.42 �� 1.5 mm), 20 non-ovigerous females (CL=3.53 �� 0.73 mm; TL=9.72 �� 1.82 mm), and 20 ovigerous females (CL=4.27 �� 0.15 mm; TL=11.91 �� 0.38 mm); muddysandy intertidal zone of the Ajuruteua Peninsula (Fig. 1A, B) in the Bragan��a region of the state of Par��, northern Brazil (046��37���8.13���W, 0��48���52.92���S; 046��36���11.81���W, 0��50���9.10���S; 046��36���9.80���W, 0��50���11.22���S); 23 June 2013, 03 March 2014, 11 April 2015, 19 March 2017, 20 May 2017, and 13 April 2018. Description. See Williams (1965, 1984) and Anker (2008). Density and population structure. A total of 360 specimens of L. forceps were obtained from the 3000 burrows of the callichirid ���ghost��� shrimp, Lepidophthalmus siriboia, sampled during the present study. Overall, 222 of the 360 L. forceps specimens were identified as males (61.7%) and 138 as females (38.3%), resulting in a sex ratio of 1.6M: 1F. In the case of the females, 101 individuals (73.2% of the total) had eggs in their abdomens. Shrimp density varied from 0 to 3 individuals per callichirid burrow. In the general, male shrimps of L. forceps exhibited carapace lengths (CL) ranging from 2.4 to 8.4 mm (3.6 �� 0.8 mm), with the highest percentages of individuals (33.3 and 22.9%) being assigned to the size classes between 3.0 and 4.0 mm CL (Fig. 7). The CLs of the non-ovigerous females ranged from 2.6 to 4.9 mm (3.3 �� 0.7 mm), and the highest percentage of females (40.5%) was recorded in the 3.0��� 3.5 mm size class (Fig. 7). The CLs of the ovigerous females ranged from 3.4 to 5.8 mm (4.2 �� 0.4 mm), with most specimens (64.3%) being recorded in the 4.0��� 4.5 mm size class (Fig. 7). The total body lengths (TL) of the male shrimps ranged from 6.3 to 18.4 mm (9.9 �� 1.7 mm), with the highest percentages of specimens (10.8���11.2%) being grouped in the size classes between 8.0 and 12.0 mm TL (Fig. 7). The TLs of the non-ovigerous females varied from 7.2 to 13.3 mm (9.0 �� 1.7 mm), with most specimens being recorded in the 8.0��� 8.5 mm (21.6%), 8.5���9.0 mm (13.5%), and 10.0��� 10.5 mm (13.5%) size classes (Fig. 7). The TLs of the ovigerous females ranged from 9.4 to 15.4 mm (11.7 �� 0.9 mm), and the highest percentages of specimens (15.8 and 33.6%) were recorded in the size classes between 11.0 and 12.5 mm TL (Fig. 7). Colour in life. Semitransparent with yellowish or purplish chromatophores, posterior abdominal somites greenish in colour; hepatopancreas greenish or orange in colour; antennular and antennal peduncles and tail fan with reddish or greenish chromatophores; presence of some chromatophores on the merus and carpus; chela colourless (Figs. 2 A���C); eggs in early stages of development bright green in colour (Fig. 2C), and those at an advanced stage of development (close to hatching) semitransparent. Distribution. Western Atlantic: from North Carolina (USA) to Venezuela and Brazil, in the states of Par�� (present study), Cear��, Para��ba, Sergipe, and Bahia; Eastern Pacific: coast of Colombia (Table 1). Ecology. In present study, the Leptalpheus specimens were collected from the burrows of the callichirid ���ghost��� shrimp, L. siriboia, in a muddy-sandy intertidal zone on the Amazon region, northern coast of Brazil (Fig. 1 A���C). Pachelle et al. (2016) also recorded L. siriboia hosting L. forceps in its burrows in the Brazilian state of Cear��. L. forceps has also been observed living in association with other burrowing shrimps from the families Upogebiidae and Callichiridae (Table 1). However, information on the feeding ecology, behaviour, reproduction, growth, embryonic and larval development of this species is still lacking, and these parameters require further investigation. Remarks. Based on its morphological similarities with a number of other Leptalpheus species, the alpheid shrimp L. forceps is currently included in an informal species group from the western Atlantic and eastern Pacific coasts, which also includes Leptalpheus mexicanus, Leptalpheus felderi, and a number of other, as yet undescribed species (Table 1). All these species share the presence of a mesial tooth on the ischium of the major cheliped, while the stylocerite does not reach the distal margin of the first segment of the antennule (Anker et al. 2006b). The actual taxonomic scenario is extremely complex, given that Leptalpheus genus appears to be closely related to the genera Richalpheus Anker & Jeng, 2006, Amphibetaeus Couti��re, 1897, and Fenneralpheus Felder & Manning, 1986. In all these genera, the margin of the carapace has no rostrum or orbital teeth, while the stylocerite is more or less compressed onto the first segment of the antennule, the major cheliped is very asymmetrical and is carried folded when unused, and the minor cheliped has a characteristic shape, with a slender merus and elongated fingers (Williams 1965; Felder & Manning 1986; Anker & Jeng 2006; Anker et al. 2006b; Anker & Dworschak 2007; Marin et al. 2014). Despite these similarities, the genus Leptalpheus is currently considered to be a sister taxon of the genus Fenneralpheus, as supported by the molecular analysis of 16s mtDNA (see Felder et al. 2003, fig. 9). The morphology of the L. forceps specimens from the Ajuruteua Peninsula, Amazon region, is much more similar to that of the specimens of L. cf. forceps from the Costa Rica and Panama described by Anker (2008, 2011) than those of L. forceps from the North Carolina (USA) described originally by Williams (1965) or the L. aff. forceps from the Brazilian state of Bahia reported by Almeida et al. (2012). The morphological similarities between the Amazonian and Central American specimens are related to the proportion of the articles of the antennule, in particular, the slightly more robust antennular peduncle, the short scaphocerite, which is no longer than half the length of the second antennular peduncle (Fig. 3A; Anker 2008, fig. 4A), and the same number of teeth (six or seven) in the major chela (Figs. 5, 6; Anker 2008, fig. 5H, L). In the present study, furthermore, a caudal filament was observed on each uropodal endopod in specimens of both sexes of L. forceps (Fig. 3D), like that described in two males of L. cf. forceps by Anker (2008, fig. 4J), albeit with varying lengths. In the Amazonian L. forceps, however, this structure was absent in most of the individuals analyzed (Fig. 3E). The same caudal filament was also observed in one male paratype of L. felderi (Anker et al. 2006b, fig. 5C), but it was also absent in other specimens of this species, and, when present, it was not as prominent as in L. cf. forceps (Anker, 2008, fig. 4J). The possible functions of this structure are still unclear and demand further research. The gap between the fingers of the major cheliped varied considerably in the L. forceps specimens collected in the present study (Figs. 5, 6). Williams (1965) noted that the fingers of the major cheliped in the females of L. forceps from North Carolina were less widely spaced than those of the males. In the specimens analyzed in our study, however, this gap did not vary systematically between males and females and, therefore, the major cheliped presented fingers with more or less gaping independent of the sex. In addition, four different morphological variations of the major cheliped in L. forceps were identified here, with the most common presenting a more protruding distal tooth and a more widely spaced gap than the others (see Figs. 5C, 6C). The variation in the fingers gap of the major cheliped of the L. cf. forceps specimens from Costa Rica (Anker 2008, fig. 5G, F, L) was very similar to that observed here in the Amazonian L. forceps (see Figs. 5A, D, 6A, D). Also, a male specimen of L. aff. forceps was found in the Brazilian state of Bahia exhibiting the major cheliped with less gaping (see Almeida et al. 2012, fig. 5C), similar to that observed in some specimens collected in the present study (see Figs. 5A, 6A). It is important to note, however, that the recognition of the variation in the morphology of the cheliped and fingers gap in our Leptalpheus specimens may only have been possible due to the relatively large sample size, in comparison with the studies of Williams (1965), Anker (2008), and Almeida et al. (2012). One additional difference is the variation in the number of teeth (six or seven) of the major chela in the Amazonian specimens analyzed here, in contrast with the six teeth of the type species (see Williams 1965, fig. 1G). The morphological diversity found within the genus Leptalpheus and the L. forceps group clearly requires more systematic investigation, as well as the application of a phylogenetic approach, to identify possible homoplasies or synapomorphies (Anker 2008)., Published as part of Ros��rio, Tayse N., Pires, Marcus A. B., Souza, Adelson S., Fernandes, Marcus E. B., Abrunhosa, Fernando A. & Simith, Darlan J. B., 2020, First known occurrence of the alpheid shrimps Leptalpheus forceps Williams, 1965 and L. marginalis Anker, 2011 (Decapoda: Caridea) in the state of Par��, Amazon region, Brazil, pp. 61-85 in Zootaxa 4766 (1) on pages 63-70, DOI: 10.11646/zootaxa.4766.1.3, http://zenodo.org/record/3763963, {"references":["Williams, A. B. (1965) A new genus and species of snapping shrimp (Decapoda, Alpheidae) from the southeastern United States. Crustaceana, 9, 192 - 198. https: // doi. org / 10.1163 / 156854065 X 00352","Williams, A. B. (1984) Shrimps, Lobsters, and Crabs of the Atlantic Coast of the Eastern United States, Maine to Florida. Smithsonian Institution Press, Washington D. C., 550 pp.","Anker, A., Vera Caripe, J. A. & Lira, C. (2006 b) Description of a new species of commensal alpheid shrimp (Crustacea, Decapoda) from the Southern Caribbean Sea. Zoosystema, 28, 683 - 702.","Pachelle, P. P. G., Anker, A., Mendes, C. B. & Bezerra, L. E. A. (2016) Decapod crustaceans from the state of Ceara, northeastern Brazil: an updated checklist of marine and estuarine species, with 23 new records. Zootaxa, 4131, 001 - 063. https: // doi. org / 10.11646 / zootaxa. 4131.1.1","Anker, A. (2008) The shrimp genus Leptalpheus Williams, 1965 in the southwestern Caribbean Sea, with description of one new species from Panama (Crustacea, Decapoda, Alpheidae). Zoosystema, 30, 781 - 794.","Anker, A. (2011) Six new species and three new records of infaunal alpheid shrimps from the genera Leptalpheus Williams, 1965 and Fenneralpheus Felder & Manning, 1986 (Crustacea, Decapoda). Zootaxa, 3041, 1 - 38. https: // doi. org / 10.11646 / zootaxa. 3041.1.1","Almeida, A. O., Boehs, G., Araujo-Silva, C. L. & Bezerra, L. E. A. (2012) Shallow-water caridean shrimps from Southern Bahia, Brazil, including the first record of Synalpheus ul (Rios & Duffy, 2007) (Alpheidae) in the southwestern Atlantic Ocean. Zootaxa, 3347, 1 - 35.","Anker, A. & Jeng, M. S. (2006) Richalpheus palmeri, N. Gen., N. Sp., an infaunal alpheid shrimp from the Philippines, with redescription of Amphibetaeus jousseaumei (Coutiere, 1896) (Decapoda: Caridea). Journal of Crustacean Biology, 26, 379 - 391. https: // doi. org / 10.1651 / S- 2647.1","Coutiere, H. (1897) Note sur quelques genres nouveaux ou peu connus d'Alpheides, formant la sous-famille des Alpheopsides. Bulletin du Museum National d'Histoire Naturelle, 2, 380 - 386. [imprint in 1896]","Felder, D. L. & Manning, R. B. (1986) A new genus and two new species of alpheid shrimps (Decapoda: Caridea) from south Florida. Journal of Crustacean Biology, 6, 497 - 508. https: // doi. org / 10.1163 / 193724086 X 00343","Anker, A. & Dworschak, P. C. (2007) Description of a new species of Richalpheus Anker and Jeng, 2006 (Crustacea: Decapoda: Alpheidae) from the Red Sea. Journal of Natural History, 41, 2331 - 2340. https: // doi. org / 10.1080 / 10503300701579943","Marin, I., Sheibani, R. & Sari, A. (2014) A re-description of rare alpheid shrimp Amphibetaeus jousseaumei (Coutiere, 1896) and description of a new species of the genus Athanopsis Coutiere, 1897 (Crustacea: Decapoda: Alpheidae) from Iranian coast of the Persian Gulf. Zootaxa, 3846, 398 - 410. https: // doi. org / 10.11646 / zootaxa. 3846.3.4","Felder, D. L., Nates, S. F. & Robles, R. R. (2003) Hurricane Mitch: Impacts of bioturbating crustaceans in shrimp ponds and adjacent estuaries of coastal Nicaragua. USGS Open File Report, 03 - 179, 1 - 70. https: // doi. org / 10.3133 / ofr 03179","Felder, D. L. & Rodrigues, S. A. (1993) Reexamination of the ghost shrimp Lepidophthalmus louisianensis (Schimitt, 1935) from the northern gulf of Mexico and comparison to L. siriboia, new species, from Brazil (Decapoda: Thalassinidae: Callianassidae). Journal of Crustacean Biology, 13, 357 - 376. https: // doi. org / 10.1163 / 193724093 X 00138"]}

Leptalpheus marginalis Anker, 2011 Figures 8���11 Leptalpheus marginalis ��� Anker 2011: 4���6, figs. 1, 2. Material examined. 10 males (CL=4.33 �� 0.61 mm; TL=11.19 �� 1.63 mm), two non-ovigerous females (CL=4.52 �� 0.68 mm; TL=11.98 �� 0.2 mm), and three ovigerous females (CL=4.49 �� 0.2 mm; TL=11.69 �� 0.2 mm); muddysandy intertidal zone of the Ajuruteua Peninsula (Fig. 1A, B) in the Bragan��a region of the state of Par��, northern Brazil (046��37���8.13���W, 0��48���52.92���S; 046��36���11.81���W, 0��50���9.10���S; 046��36���9.80���W, 0��50���11.22���S); 23 June 2013, 3 March 2014, 11 April 2015, 19 March 2017, 20 May 2017, and 13 April 2018. Description. See Anker (2011). Density and population structure. L. marginalis was less abundant than L. forceps, and was encountered only rarely in the study area. In fact, only 48 specimens were captured from the 3000 L. siriboia burrows sampled during the present study. From the total number of L. marginalis specimens collected, 38 individuals were identified as males (79.2%) and 10 as females (20.8%), resulting in an overall sex ratio of 3.8M: 1F. Eight (80% of the total) of the females had eggs in their abdomens. The density of L. marginalis ranged from 0 to 1 specimen per callichirid burrow. The carapace lengths (CL) of the male shrimps ranged from 2.6 to 5.2 mm (4.1 �� 0.7 mm), with the highest percentages of specimens being recorded in the 3.0��� 3.5 mm (23.7%) size class and in the classes between 4.0 and 5.0 mm CL (26.3%) (Fig. 12). The non-ovigerous females (n=2) had CLs of 4.0 and 5.0 mm, while the CLs of the ovigerous specimens ranged from 3.5 to 4.7 mm (4.3 �� 0.4 mm), with most (75%) of the individuals being recorded in the 4.0��� 4.5 mm size class (Fig. 12). The male shrimps presented total body lengths (TL) ranging from 6.7 to 14.1 mm (10.7 �� 1.6 mm), with the highest frequencies of the specimens being grouped in the 8.5���9.0 mm (13.2%) size class, in the classes between 10.5 and 11.5 mm TL (13.2 and 15.8%), and in the 12.0��� 12.5 mm (15.8%) size class (Fig. 12). The two non-ovigerous females had TLs of 11.8 and 12.1 mm. The TLs of the ovigerous specimens ranged from 10.6 to 12.1 mm (11.6 �� 0.5 mm) and most of the specimens were included in the 10.5���11.0 mm (25%) and 11.5���12.0 mm (50%) size classes (Fig. 12). Colour in life. Body semitransparent, with numerous reddish or purplish chromatophores forming diffuse bands around the abdomen; hepatopancreas greenish or orange in colour; the posterior margin of the abdominal somites with greenish chromatophores; antennae, antennules, tail fan, and chelipeds with concentrations of greenish or reddish chromatophores (Fig. 8 A���C); eggs bright green in early stages of development and semitransparent when close to hatching (Fig. 8C). ......continued on the next page ......continued on the next page ......continued on the next page Distribution. Previously known only from the type locality on the Caribbean coast of Colombia (see Anker 2011). Now also known from the Ajuruteua Peninsula in the Bragan��a region, northeastern coast of the state of Par��, Amazon region, Brazil (present study). Ecology. The present study represents the first report of the presence of L. marginalis living in burrows of the callichirid ���ghost��� shrimp, L. siriboia, in a muddy-sandy intertidal habitat in northern Brazil (Fig. 1 A���C). Given the cryptic life style of this and other Leptalpheus species, data on their feeding behaviour, ecology, breeding season, growth, and embryonic and larval development are still non-existent, and require further investigations. Remarks. In the present study, L. marginalis of both sexes from the Ajuruteua Peninsula, Amazon region, were analyzed and compared with Anker���s (2011) description of the male holotype from the coast of Colombia. According to Anker (2011), L. marginalis can be differentiated from other Leptalpheus species primarily by the lack of a gap when the fingers of the major chela are closed (Fig. 10C, D; Anker 2011, fig. 2E). The morphology of the Amazonian specimens is broadly consistent with that of the male holotype from Colombia. However, L. marginalis from the Amazon region have more robust antennular articles and a slightly more rounded frontal margin of the carapace (see Fig. 9A, B) than the Colombian holotype (see Anker 2011, fig. 1A). Also, our specimens showed a third maxilliped slightly more elongated with an exopod 5-segmented and an ultimate segment divided in 12 narrow segments (see Fig. 11D) in contrast to L. marginalis described by Anker (2011, fig. 1I). Other important differences are related to the presence or absence of orbital crests in front of the eyes (Fig. 9A, B; Anker 2011, fig. 1A���C), and of an appendix (i.e., caudal filament) on each uropodal endopod, sometimes segmented or not (Fig.11 A���C; Anker 2011, fig. 1M). In the Amazonian specimens, the presence or absence of these orbital crests or caudal filaments was randomly recorded in both the larger adults and juveniles of both sexes. The presence of orbital crests situated near the anterolateral margin of the carapace was also reported in the literature for other Leptalpheus specie s such as Leptalpheus bicristatus from Chame Bay, Pacific coast of Panama (Anker 2011, fig. 15A, B), L. felderi from Isla Margarita, Venezuela, and Bah��a Cispata, Colombia (Anker et al. 2006b, fig. 1A���C), and L. mexicanus from Estero de Ur��as, Mazatl��n, Sinaloa, Mexico (Salgado-Barrag��n et al. 2014, fig. 6A, B, E, F). Caudal filaments on uropodal endopods have also been described in L. cf. forceps from Costa Rica (Anker 2008, fig. 4J), in L. forceps from Ajuruteua Peninsula, Brazil (present study, Fig. 3D), and in L. felderi from Venezuela (Anker et al. 2006b, fig. 5C). It is likely that the L. marginalis from the coast of Colombia could also present the same pattern of variation found in the Amazonian specimens. The fact that Anker (2011) has analyzed only three male specimens, the morphological characters described by this author may not be conclusive, and more specimens should be analyzed to elucidate these differences. The marginal crests were described by Anker (2011) as one of a number of taxonomic characters used for differentiating L. marginalis from other Leptalpheus species (e.g., L. forceps, L. mexicanus, Leptalpheus pierrenoeli, and Leptalpheus axianassae). The variation in the presence of orbital crests observed in our study may therefore indicate an intraspecific variability among geographically isolated populations and these structures should not longer be considered as a good morphological character for phylogenetic separation. This variation was also documented by Salgado-Barrag��n et al. (2014) for L. mexicanus. These authors suggested the exclusion of these orbital crests as distinctive character between L. mexicanus and L. bicristatus. The functional morphology of the orbital crests and the caudal filaments in L. marginalis and other congeneric species is still unclear. The presence or absence of these structures may reflect either phenotypic adaptations to the environment or genetic variation. Given the considerable morphological variation found in the genus Leptalpheus, further research is required to determine whether this intraspecific variation has a genetic basis., Published as part of Ros��rio, Tayse N., Pires, Marcus A. B., Souza, Adelson S., Fernandes, Marcus E. B., Abrunhosa, Fernando A. & Simith, Darlan J. B., 2020, First known occurrence of the alpheid shrimps Leptalpheus forceps Williams, 1965 and L. marginalis Anker, 2011 (Decapoda: Caridea) in the state of Par��, Amazon region, Brazil, pp. 61-85 in Zootaxa 4766 (1) on pages 71-81, DOI: 10.11646/zootaxa.4766.1.3, http://zenodo.org/record/3763963, {"references":["Anker, A. (2011) Six new species and three new records of infaunal alpheid shrimps from the genera Leptalpheus Williams, 1965 and Fenneralpheus Felder & Manning, 1986 (Crustacea, Decapoda). Zootaxa, 3041, 1 - 38. https: // doi. org / 10.11646 / zootaxa. 3041.1.1","Williams, A. B. (1965) A new genus and species of snapping shrimp (Decapoda, Alpheidae) from the southeastern United States. Crustaceana, 9, 192 - 198. https: // doi. org / 10.1163 / 156854065 X 00352","Schmitt, W. L. (1924) The macruran, anomuran and stomatopod Crustacea. Bijdragen tot de kennis der fauna van Curacao. Resultaten eener reis van Dr. C. J. van der Horst in 1920. Bijdragen tot de Dierkunde, 23, 61 - 81.","Borradaile, L. A. (1903) On the classification of the Thalassinidea. Annals and Magazine of Natural History, 12, 534 - 551. https: // doi. org / 10.1080 / 00222930308678891","Manning, R. B. & Felder, D. L. (1991) Revision of the American Callianassidae (Crustacea: Decapoda: Thalassinidea. Proceedings of the Biological Society of Washington, 104, 764 - 792.","Poore, G. C. B., Dworschak, P. C., Robles, R., Mantelatto, F. L. & Felder, D. L. (2019) A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support. Memoirs of Museum Victoria, 78, 73 - 146. https: // doi. org / 10.24199 / j. mmv. 2019.78.05","WoRMS Editorial Board (2020) World Register of Marine Species: Callichiridae Manning & Felder, 1991. Available from http: // www. marinespecies. org / aphia. php? p = taxdetails & id = 1397714 (accessed 27 February 2020). https: // doi. org / 10.14284 / 170","Dworschak, P. C. & Coelho, V. R. (1999) On two alpheids from Araca (Sao Paulo, Brazil) with description of a new species of Leptalpheus (Decapoda: Caridea: Alpheidae). Annalen des Naturhistorischen Museums in Wien, 101 B, 475 - 488.","Ramos-Porto, M. & Souza, S. T. (1994) Descricao de Leptalpheus petronii sp. n. (Decapoda, Alpheidae) para o Brasil. In: Bo- necker, S. L. C. (Ed.), Resumos do XX Congresso Brasileiro de Zoologia, 24 - 29 de julho 1994. Universidade Federal do Rio de Janeiro, Rio de Janeiro, pp. 22.","Dos Santos, M. A. C. & Coelho, P. A. (2001) Crustacea Decapoda of the Paripe River Estuary, Pernambuco, Brazil. Hydrobiologia, 449, 77 - 79. https: // doi. org / 10.1023 / A: 1017536902549","Felder, D. L., Nates, S. F. & Robles, R. R. (2003) Hurricane Mitch: Impacts of bioturbating crustaceans in shrimp ponds and adjacent estuaries of coastal Nicaragua. USGS Open File Report, 03 - 179, 1 - 70. https: // doi. org / 10.3133 / ofr 03179","Almeida, A. O., Boehs, G., Araujo-Silva, C. L. & Bezerra, L. E. A. (2012) Shallow-water caridean shrimps from Southern Bahia, Brazil, including the first record of Synalpheus ul (Rios & Duffy, 2007) (Alpheidae) in the southwestern Atlantic Ocean. Zootaxa, 3347, 1 - 35.","Botter-Carvalho, M. L., Costa, L. B., Gomes, L. L., Clemente, C. C. C. & Carvalho, P. V. V. C. (2015) Reproductive biology and population structure of Axianassa australis (Crustacea, Axianassidae) on a sand-mud flat in north-eastern Brazil. Journal of the Marine Biological Association of the United Kingdom, 95, 735 - 745. https: // doi. org / 10.1017 / S 002531541400174 X","Pachelle, P. P. G., Anker, A., Mendes, C. B. & Bezerra, L. E. A. (2016) Decapod crustaceans from the state of Ceara, northeastern Brazil: an updated checklist of marine and estuarine species, with 23 new records. Zootaxa, 4131, 001 - 063. https: // doi. org / 10.11646 / zootaxa. 4131.1.1","Almeida, A. O., Terossi, M., Buranelli, R. C., Castilho, A. L., Costa, R. C., Zara, F. J. & Mantelatto, F. L. (2018) Checklist of decapods (Crustacea) from the coast of Sao Paulo State (Brazil) supported by integrative molecular and morphological data: II. Infraorder Caridea: family Alpheidae. Zootaxa, 4450 (3), 331 - 358. https: // doi. org / 10.11646 / zootaxa. 4450.3.2","Williams, A. B. 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Rosário, Tayse N., Pires, Marcus A.B., Souza, Adelson S., Fernandes, Marcus E.B., Abrunhosa, Fernando A., Simith, Darlan J.B. (2020): First known occurrence of the alpheid shrimps Leptalpheus forceps Williams, 1965 and L. marginalis Anker, 2011 (Decapoda: Caridea) in the state of Pará, Amazon region, Brazil. Zootaxa 4766 (1): 61-85, DOI: 10.11646/zootaxa.4766.1.3

Alison D Early, Sarah Adelson, Craig J Miller, Thomas F Mauger Department of Ophthalmology, The Ohio State University Havener Eye Institute, Columbus, OH, USA Objective: To evaluate smoking and alcohol use as risk factors for higher-grade dysplasia in a population of patients with histopathologically proven ocular surface squamous neoplasia. Materials and methods: This is a retrospective chart review of data extracted from a database comprising demographic information and medical diagnosis information based on International Classification of Disease codes. Outcome measures were analyzed using the Wilcoxon two-sided test, a non-parametric t-test. Results: Database review yielded 35 patients with ocular surface squamous neoplasia lesions proven by histopathologic analysis. The mean age was 64.51 years with SD 17.54 years. Patients were 28.57% female and 71.43% male. Nearly all patients were White (88.57%), and 5.71% were African American, 2.86% Hispanic, and 2.86% Other. There was no significant difference in dysplasia grade between smokers and non-smokers (P=0.7044), those who used alcohol vs did not use alcohol (P=0.2470), those who used tobacco and alcohol vs those who did not (P=0.5117), and those who used either tobacco or alcohol vs those who did not (P=0.8259). Conclusion: No statistically significant relationship was found between high-grade dysplasia and cigarette smoking, alcohol use, or both cigarette smoking and alcohol use. Keywords: ocular surface squamous neoplasia, corneal dysplasia, conjunctival dysplasia, carcinoma in situ, squamous cell carcinoma, ocular surface tumors

This article discusses how to estimate the Fourier spectra of irregularly sampled multidimensional functions in an approximate way, using current fast Fourier transform (FFT) algorithms. This estimate may be an alternative for more rigorous approaches when the inversion of huge matrices is prohibitively expensive. The approximation results from a Taylor expansion of the Fourier transform kernel, which is a series on the product of wavenumbers and displacements from centers of a grid where a regular, discrete Fourier transform (DFT) is defined. Convergence and efficiency, as well as some shortcuts for implementation, is indicated. The problem of finding a Fourier spectrum of a function given a finite set of irregular measurements is usually associated with the idea of regularization/interpolation. This, in turn, raises the question of representativeness of continuous functions via its discrete measurements. Although this question is central for the very Fourier spectrum estimation, the scope of this article will be restricted to the trigonometric interpolation, postponing representativeness issues. For the sake of simplicity, the proposed approximation is first derived for the one-dimensional (problem where most related aspects are more clearly stated. Then, extensions to higher dimensions are straightforwardly presented.

Ensaio

This study aimed to evaluate the safety of the hydroalcoholic extract (HE) of Syzygium cumini (L.) Skeels, Myrtaceae, leaves in rodents. Acute toxicity was evaluated through the determination of a LD50 in mice and rats (up to 14 days). In mice, the oral administration (p.o.) of the HE (0.1 at 6 g/kg) did not cause any death. When administered by intraperitoneal route (i.p.) the HE (0.1 at 1 g/kg) caused death of the animals (LD50 of 0.489 g/kg). In rats, the HE (0.5, 1 and 2 g/kg, p.o.) did not cause any death, while by i.p., only the 2 g/kg dose was lethal to 67% of the animals. To evaluate chronic toxicity, groups of rats daily received the HE (0.05, 0.1 and 0.25 g/kg) through p.o., during 30, 90 or 180 days and the effects on behavior, body weight, feed consumed were measured. Histology, hematology and biochemical parameters were measured at the end of the treatment. After a 30-day treatment, the HE caused changes in some biochemical parameters. Histological examination of the liver, kidneys, lungs, heart, stomach, intestine and pancreas showed normal architecture suggesting no morphological disturbances. These data may mean that the HE of S. cumini does not exert acute or chronic toxic effects by oral administration.

The safety of babassu mesocarp (Orbignya phalerata Mart., Arecaceae), which exhibited anti-inflammatory and antithrombotic activities, was evaluated by determining the potential acute toxicity in mice. A lyophilized ethanol extract of babassu mesocarp (BME) was administered to C3H/HePas mice (10/group) in a single dose of 1000, 3000 and 5000 mg/kg, by gavage. General behavior adverse effects and mortality were determined for up to fourteen days. Selected biochemical parameters including glucose, triacylglyceride, cholesterol, urea, alkaline phosphatase and creatinine were determined by colorimetric assay. The heart, liver, spleen, kidneys and brain were weighted and evaluated macro and microscopically. The median lethal dose (LD50) of BME was greater than 5000 mg/kg. No behavior or body weight alterations were detected after the treatment. The acute treatment with BME has no effect on macroscopic and microscopic aspect of examined organs. Instead, BME increased the alkaline phosphatase and reduced the urea concentration in all groups. A significant increase on triacylglyceride was detected in the group BME1000. In conclusion, the acute treatment with high doses of BME can affect some biochemical parameters with a long lasting effect, although any change was detected at tissue level or body and organ weight.

Babassu is the popular name of Orbignya phalerata Mart. (Arecaceae). The mesocarp flour obtained from their fruits has been used in Brazil as medicine in the treatment of pains, constipation, obesity, leukemia, rheumatism, ulcerations, tumors, inflammations and venous diseases. The effect of the chronic oral treatment with aqueous extract of babassu mesocarp (500mg/kgday) on the number of platelets, the prothrombin time (PT), the activated partial thromboplastin time (aPTT), the nitric oxide (NO) production and the carrageenin-induced thrombosis was evaluated, using C57Bl/6 mice. The chronic oral treatment with babassu mesocarp induced an anti-thrombotic effect. There was a 88.9% reduction in the necrosis of the tail. This effect seems to be related to an increase in the ability of the macrophage to produce NO and to a slow coagulation process associated to an increase of 12.0 and 13.9% in PT and aPTT, respectively. However, the anti-thrombotic effect seems to be not related to alterations in the number of platelets. It is possible to conclude that the oral treatment with babassu mesocarp has a significant anti-thrombotic effect, which could justify the popular use of babassu mesocarp in the treatment of venous diseases. Meanwhile, this study suggests a potential use of babassu mesocarp as a prophylactic agent to avoid thrombosis events.

This paper discusses a deterministic signature-estimation method for marine seismic data. This method assumes that the direct wave is known and all notionals can be represented as a scaled version of an effective notional.

The sparseness in seismic data has been successfully used to achieve many improvements in different areas such as acquisition, regularization, filtering, and imaging. The search for a sparse description for a given practical seismic (linear) problem is often conducted via the so called Iteratively Reweighted Least-Squares Inversion with an adaptive choice of a diagonal matrix, computed with a statistically derived prescription. In this paper, we discuss the role of this matrix in the inversion and propose an alternative heuristic formula which allows one to more easily constrain the solution to physical expectations and is likely to improve sparseness and accelerate convergence. Introduction and Review Linear inversion problems are very common in geophysical applications. Usually, a set of representative vectors are combined in a weighted way so as to fit a set of measurements. Mathematically, it is to say A~x = ~b, where A is a matrix with model vectors in its columns, ~x is a vector of weights to be determined, and ~b is the data vector. The choice of the model vectors is generally guided by physical demands and is not committed to fill simple mathematical properties like completeness or uniqueness of the solution ~x. For instance, in an irregular discrete Fourier transform (IDFT), columns of A exhibits the values of sinusoidal functions taken at unevenly chosen positions. Thus, the matrix A for IDFT departs a lot from the usual discrete Fourier transform. A may not be invertible and the solution ~x may not be unique. Least square (L2) error (‖A~x−~b‖2) is an option to define ~x for overdetermined problems. Developing a linear problem to L2 minimum error norm leads to equations like AHA~x = AH~b (1). Underdetermined and/or ill-posed problems are often handled with a dumped version of the L2 error norm (here called the Dumped Least Square equation or DLSE) as (AHA + λ I)~x = AH~b where λ is ideally chosen real, positive, and small enough to allow for a solution that keeps the error as small as possible, and I is the identity. At this point, it might be noticed that extending the original linear problem as, [ A √ λ I ]

The propolis of Scaptotrigona aff. postica is popularly used in Maranhao State, Brazil, for treating wounds and respiratory illnesses. Nevertheless, little is known about the chemical composition of this propolis and the adverse effects of its use. Hence, this study is a pharmacognostic characterisation of the propolis hydroalcoholic extract (PHE) from S. aff. postica. The methodology consisted of an evaluation of the sensory and chemical parameters. Chemical analysis of PHE indicated high concentrations of phenolic and triterpens substances, and the absence of steroids. Additionally, we evaluated the acute toxicity of propolis using 48 Swiss male and female mice. The animals received single doses of PHE (1000, 2000 or 4000 mg kg⁻¹) orally and were observed for 14 days. After this period, the mice were sacrificed and the blood was used for biochemical and haematological evaluation. PHE did not induce any death, and the acute treatment significantly reduced serum concentrations of alanine aminotransferase and alkaline phosphatase. The resultant data indicate that PHE from S. aff. postica has low toxicity when used orally, even in high doses.

An implementation of a recently proposed technique using seismic attribute for the inference of fluid mobility was tested in two brazilian reservoirs. Results have shown good agreement with predictions based on well log information. Here we also present a discussion of this tests based on reservoir characteristics. Introducao

Spectral Decomposition is a very useful tool for the identification of stratigraphic features, especially in the characterization of thin reservoir. However, Spectral Decomposition is based on the windowed Discrete Fourier Transform, which provides a less optimized timefrequency analysis. The S Transform differs from the windowed Fourier Transform in the adoption of a window model whose width is adjusted to the frequency that is analyzed. This confers the S Transform properties similar to those of wavelets Transforms in terms of time-frequency resolution. This paper presents results of the application of the S Transform to the spectral decomposition of synthetic and real seismic data.

Babassu is the popular name of Orbignya phalerata Mart. [Arecaceae (Palmae)], which fruits mesocarp has been used in Brazil as medicine for the treatment of pains, constipation, obesity, leukemia, rheumatism, ulcerations, tumors and inflammations. In this study, we investigated the effect of babassu mesocarp flour aqueous extract (BM) on C3H/HePas mice peritoneal cellular migration and macrophage activation by measuring the nitric oxide (NO), hydrogen peroxide (H(2)O(2)) and tumor necrosis factor (TNF) release, spreading activity and major histocompatibility complex (MHC) class II expression. Our results demonstrate that BM injected once ip in mice at 10 and 20 mg/kg increased the cellular influx to the peritoneal cavity, the MHC class II expression and the spreading ability, and also induced the production of NO, TNF and H(2)O(2). The increase in NO-production and MHC expression was also observed after the addition of BM to resident macrophage cultures (100 microg/ml). Thus, BM-treatment was able to activate peritoneal macrophages in vitro and in vivo inducing the production of inflammatory and cytotoxic metabolites, which could justify the popular use of babassu mesocarp in the treatment of tumor diseases, but not in inflammatory pathologies.

SUMMARY We discuss the application of true-amplitude Dip MoveOut (DMO) to amplitude versus offset (AVO) studies on real marine seismic data. This process is expected to be accurate at least to mild lateral velocity variations. Besides the usual kinematics of any DMO process, true amplitude DMO is designed to properly deal with the variations in the geometrical spreading losses with offset. After the application of a true- amplitude DMO, primary reflections in the input CO section are transformed into their corresponding ZO primary reflections so that (a) geometrical spreading losses are automatically transformed and (b) reflection coefficients remain unchanged. The process affects, thus, the desired compensation of the offset-dependent, geometricalspreading, which is needed for a reliable AVO analysis. The performance of the proposed true-amplitude DMO algorithm to correctly compensate geometricalspreading losses at large offsets is examined. For a known gas anomaly the AVO gradient section showed larger absolute values, indicating larger amplitude compensation not predicted by conventional methods. The reliable results obtained by the proposed method have shown to be useful for AVO analysis at least in areas with relatively small structural complexity.

We discuss the application of true-amplitude migration to zero offset (MZO) to amplitude versus offset (AVO) studies on a real marine seismic data. The true-amplitude MZO is achieved by means of a cascaded application of standard normal moveout correction (NMO) plus a constant-velocity, true-amplitude dip moveout (DMO). This process is expected to be precise as long as we have only mild lateral velocity variations. The impact of the compensation of geometrical spreading losses from large offsets to short ones on AVO analysis is discussed. The reliable results obtained for dipping events makes this process interesting for AVO analysis in areas of relatively small structural complexity.

The process of simulating a zero-offset (ZO) section from a given common-offset (CO) section so that primary reflections in the simulated section have the correct, (ZO) geometrical spreading, is called true-amplitude migration to zero offset (MZO). A recently proposed Kirchhoff-type, true-amplitude MZO algorithm for 2.5-dimensional models with laterally varying velocity is implemented on simple synthetic examples. The main steps of the algorithm are the construction oi"ihe stacking line and weight function for each point on the ZO section to be simulated. These include the computation of a traveltime table for construction of CO isochrones by an eikonal equation approach, as well as dynamical tracing of certain rays for each point on each isochrone. In particular, the in-plane CO isochrone curvatures are needed in the process. Comparison of the simulated ZO section with the one directly computed from the model, confirms the validity of the proposed algorithm.

The loss of low frequencies of recorded seismic data influences the choice of the inversion scheme to be used. In this paper we discuss a modification of the inversion scheme based on the RMS Born approximation to accommodate this loss. It appears that the loss of low frequencies leads to a simple expression for the reflected field. To employ optimally the properties of the modified RMS velocity, the scheme best operates on CMP gathers. We distinguish two steps. First the stacking velocities and their corresponding two-way travel times are determined. Secondly, the actual inversion step amounts to a minimization procedure over an appropriate stacking window in the CMP domain.