Pisidia longimana (Risso, 1816), a junior synonym of P. bluteli (Risso, 1816) (Crustacea: Decapoda: Anomura: Porcellanidae) and a species distinct from P. longicornis (Linnaeus, 1767)

Pisidia longimana (Risso, 1816) and P. bluteli (Risso, 1816), both described from Nice, France, have been considered each other’s synonyms or have been validated depending on successive taxonomic opinions. The validity of both in respect to P. longicornis (Linnaeus, 1767) has also been contradicted a number of times. The current lack of clarity in the use of the names P. longicornis, P. longimana and P. bluteli has resulted in nomenclatural instability, but also in unreliability and miscommunication as regards the available ecological and distributional information. The validity of P. bluteli and P. longimana is revisited herein based on a large number of specimens (241 males, 190 females and 33 juveniles) from many different localities. The latter species is confirmed as a junior synonym of the former, whereas P. bluteli and P. longicornis are herein considered separate species. Diagnostic characters and morphological variations are discussed and illustrated.

Pisidia longimana (Risso, 1816), a junior synonym of P. bluteli (Risso, 1816) (Crustacea: Decapoda: Anomura: Porcellanidae) and a species distinct from P. longicornis (Linnaeus, 1767)

Pisidia longimana (Risso, 1816) and P. bluteli (Risso, 1816), both described from Nice, France, have been considered each others synonyms or have been validated depending on successive taxonomic opinions. The validity of both in respect to P. longicornis (Linnaeus, 1767) has also been contradicted a number of times. The current lack of clarity in the use of the names P. longicornis, P. longimana and P. bluteli has resulted in nomenclatural instability, but also in unreliability and miscommunication as regards the available ecological and distributional information. The validity of P. bluteli and P. longimana is revisited herein based on a large number of specimens (241 males, 190 females and 33 juveniles) from many different localities. The latter species is confirmed as a junior synonym of the former, whereas P. bluteli and P. longicornis are herein considered separate species. Diagnostic characters and morphological variations are discussed and illustrated.(AU)

New records of two species of parasitic isopods (Isopoda: Cymothoida: Bopyridae: Athelginae) associated with hermit crabs from the south Atlantic

Two species of bopyrid isopods from the subfamily Athelginae are recorded from new localities in northeastern Brazil. Parathelges foliatus Markham, 1972 was recorded for the first time from Brazil, in the state of Ceará, parasitising the hermit crab Clibanarius symmetricus (Randall, 1840). Pseudostegias atlantica Lemos de Castro, 1965 is recorded from the state of Ceará, parasitising Clibanarius antillensis Stimpson, 1859. Illustrations, species diagnosis and an updated distribution map are given for each species.

New records of two species of parasitic isopods (Isopoda: Cymothoida: Bopyridae: Athelginae) associated with hermit crabs from the south Atlantic

Two species of bopyrid isopods from the subfamily Athelginae are recorded from new localities in northeastern Brazil. Parathelges foliatus Markham, 1972 was recorded for the first time from Brazil, in the state of Ceará, parasitising the hermit crab Clibanarius symmetricus (Randall, 1840). Pseudostegias atlantica Lemos de Castro, 1965 is recorded from the state of Ceará, parasitising Clibanarius antillensis Stimpson, 1859. Illustrations, species diagnosis and an updated distribution map are given for each species.(AU)

On the identity of Porcellana paivacarvalhoi Rodrigues da Costa, 1968 (Crustacea: Anomura: Porcellanidae)

Porcellana paivacarvalhoi Rodrigues da Costa, 1968, described from southeastern Brazil (São Sebastião, São Paulo), is morphologically similar to the eastern Atlantic P. platycheles (Pennant, 1777), and also to the west African P. africana Chace, 1956. The synonymy between P. paivacarvalhoi and P. platycheles was proposed by previous authors without examination of any specimens of P. platycheles, nor did they considered the morphological similarities between P. paivacarvalhoi and P. africana. This synonymy has been implicitly accepted without further analysis. The recent discovery of one male and two females syntypes of P. paivacarvalhoi has prompted new investigations into the status of P. paivacarvalhoi as a junior synonym either of P. platycheles or P. africana. Porcellana paivacarvalhoi is redescribed and illustrated based upon its lectotype herein designated. It is confirmed to be a junior synonym of P. platycheles; all evidence suggests that P. africana is a distinct, separate species. All previous records of P. platycheles from the Brazilian coast are reviewed. Its presence in southeastern Brazil in the late 1960’s most probably represents an historical case of human-mediated introduction by shipping activities. Porcellana platycheles did not manage to establish itself in São Sebastião, nor has it been recorded subsequently elsewhere in Brazil.

On the identity of Porcellana paivacarvalhoi Rodrigues da Costa, 1968 (Crustacea: Anomura: Porcellanidae)

Porcellana paivacarvalhoi Rodrigues da Costa, 1968, described from southeastern Brazil (São Sebastião, São Paulo), is morphologically similar to the eastern Atlantic P. platycheles (Pennant, 1777), and also to the west African P. africana Chace, 1956. The synonymy between P. paivacarvalhoi and P. platycheles was proposed by previous authors without examination of any specimens of P. platycheles, nor did they considered the morphological similarities between P. paivacarvalhoi and P. africana. This synonymy has been implicitly accepted without further analysis. The recent discovery of one male and two females syntypes of P. paivacarvalhoi has prompted new investigations into the status of P. paivacarvalhoi as a junior synonym either of P. platycheles or P. africana. Porcellana paivacarvalhoi is redescribed and illustrated based upon its lectotype herein designated. It is confirmed to be a junior synonym of P. platycheles; all evidence suggests that P. africana is a distinct, separate species. All previous records of P. platycheles from the Brazilian coast are reviewed. Its presence in southeastern Brazil in the late 1960s most probably represents an historical case of human-mediated introduction by shipping activities. Porcellana platycheles did not manage to establish itself in São Sebastião, nor has it been recorded subsequently elsewhere in Brazil.(AU)

Chaetotaxy and setal diversity of grooming legs in species of porcelain crabs (Crustacea: Anomura: Porcellanidae)

The morphology of the fifth pereiopods was studied under scanning electron microscopy in ten species of porcelain crabs for chaetotaxy and setal diversity, namelly Megalobrachium pacificum, Megalobrachium roseum, Pachycheles grossimanus, Petrolisthes armatus, Petrolisthes tuberculatus, Pisidia brasiliensis, Pisidia longicornis, Polyonyx gibbesi, Porcellana platycheles and Porcellana sayana. Six setal types were identified: simple, pappose, sickle-shaped serrate, straight serrate, club-shaped and tooth-like cuspidate. Porcelain crabs can differ in the fifth pereiopod setal morphology, chaetotaxy and setal density, even among species within the same genus. The absence of sexual dimorphism of the grooming legs in porcelain crabs suggests that grooming eggs requires no particular grooming apparatus in females and that male and female are equal in grooming efficiency.

Chaetotaxy and setal diversity of grooming legs in species of porcelain crabs (Crustacea: Anomura: Porcellanidae)

The morphology of the fifth pereiopods was studied under scanning electron microscopy in ten species of porcelain crabs for chaetotaxy and setal diversity, namelly Megalobrachium pacificum, Megalobrachium roseum, Pachycheles grossimanus, Petrolisthes armatus, Petrolisthes tuberculatus, Pisidia brasiliensis, Pisidia longicornis, Polyonyx gibbesi, Porcellana platycheles and Porcellana sayana. Six setal types were identified: simple, pappose, sickle-shaped serrate, straight serrate, club-shaped and tooth-like cuspidate. Porcelain crabs can differ in the fifth pereiopod setal morphology, chaetotaxy and setal density, even among species within the same genus. The absence of sexual dimorphism of the grooming legs in porcelain crabs suggests that grooming eggs requires no particular grooming apparatus in females and that male and female are equal in grooming efficiency.(AU)

Growth, sexual maturity and sexual dimorphism of Aegla georginae (Decapoda: Anomura: Aeglidae) in a tributary of the Ibicuí River in southern Brazil

This study aimed to estimate the growth and size at the onset of sexual maturity in a population of Aegla georginae . Specimens were sampled from November 2007 to October 2008 in the Perau Creek (Ibicuí-Mirim sub-basin; Uruguay River basin). All captured specimens were sexed, and their cephalothoracic length (CL), minor and larger propodi length (MPL, LPL, respectively), height of major chela (HMQ), and abdomen width (AW) were measured. The lengthwise growth of males and females was evaluated using the Bertalanffy model, and the morphological sexual maturity was evaluated using the REGRANS program. The smallest ovigerous female presented a 10.45 mm CL. Males reached larger sizes than did females, but the growth rate was similar between the sexes. Longevity estimates for males and females were 670 and 736 days, respectively. The best relationship used to infer the size at morphological sexual maturity in males was CLxHMQ (12.78 mm) and in females was CLxAW (10.78 mm). Aegla georginae follows a common pattern for aeglids in terms of lifecycle, where sexual dimorphism is associated with the onset of morphological sexual maturity.

Growth, sexual maturity and sexual dimorphism of Aegla georginae (Decapoda: Anomura: Aeglidae) in a tributary of the Ibicuí River in southern Brazil

This study aimed to estimate the growth and size at the onset of sexual maturity in a population of Aegla georginae . Specimens were sampled from November 2007 to October 2008 in the Perau Creek (Ibicuí-Mirim sub-basin; Uruguay River basin). All captured specimens were sexed, and their cephalothoracic length (CL), minor and larger propodi length (MPL, LPL, respectively), height of major chela (HMQ), and abdomen width (AW) were measured. The lengthwise growth of males and females was evaluated using the Bertalanffy model, and the morphological sexual maturity was evaluated using the REGRANS program. The smallest ovigerous female presented a 10.45 mm CL. Males reached larger sizes than did females, but the growth rate was similar between the sexes. Longevity estimates for males and females were 670 and 736 days, respectively. The best relationship used to infer the size at morphological sexual maturity in males was CLxHMQ (12.78 mm) and in females was CLxAW (10.78 mm). Aegla georginae follows a common pattern for aeglids in terms of lifecycle, where sexual dimorphism is associated with the onset of morphological sexual maturity.(AU)