Ecological distribution and population structure of Acantholobulus schmitti (Rathbun, 1930) (Crustacea, Decapoda, Xanthoidea) on the southeastern Brazilian coast

This investigation analyzed the ecological distribution and population structure of A. schmitti on the southeastern coast of Brazil. Crabs were sampled monthly from January 1998 to December 1999 at the following bays: Ubatumirim (UBM), Ubatuba (UBA) and Mar Virado (MV). Water and sediment samples were also collected from all sampling sites for an analysis of environmental factors. Acantholobus schmitti was most abundant at UBM (224), followed by UBA (154) and MV (23) but its abundance showed no association with the environmental factors analyzed. The low abundance of these crabs in MV may be due to the high wave action that moved biodetritic material accumulated on the bottom and frequently removed small crabs from their sheltered positions among the shell fragments. The individuals captured included 269 males and 132 females, of which only 4 specimens were brooding females. Juvenile recruitment occurred throughout the year, but was less intense in the spring. The major abundance of individuals as well as of ovigerous females occurred during 1999, when the entrance of the South Atlantic Central Waters (SACW) was stronger than in previous year. This environmental influence could be the main factor modulating this population

Range extensions along western Atlantic for Epialtidae crabs (Brachyura, Majoidea) genera Acanthonyx Latreille, 1828 and Epialtus H. Milne Edwards, 1834

The present study provided information extending the known geographical distribution of three species of majoid crabs, the epialtids Acanthonyx dissimulatus Coelho, 1993, Epialtus bituberculatus H. Milne Edwards, 1834, and E. brasiliensis Dana, 1852. Specimens of both genera from different carcinological collections were studied by comparing morphological characters. We provide new data that extends the geographical distributions of E. bituberculatus to the coast of the states of Paraná and Santa Catarina (Brazil), and offer new records from Belize and Costa Rica. Epialtus brasiliensis is recorded for the first time in the state of Rio Grande do Sul (Brazil), and A. dissimulatus is reported from Quintana Roo, Mexico. The distribution of A. dissimulatus, previously known as endemic to Brazil, has a gap between the states of Espírito Santo and Rio de Janeiro. However, this restricted southern distribution is herein amplified by the Mexican specimens

Mithracinae (Decapoda: Brachyura) from the Brazilian coast: review of the geographical distribution and comments on the biogeography of the group

The geographical distribution of marine organisms, as a result of complex natural processes through geological time, has been changed, sometimes drastically, by species introductions. Instances of species introduction have been recorded worldwide, and the Brazilian coast is no exception. The present review provides an update of the geographical distribution of members of the brachyuran subfamily Mithracinae along the Brazilian coast. Of the 30 species of this subfamily recorded from Brazilian waters, the known geographical limits of more than 17 have been extended in recent decades. The records compiled here demonstrate the great importance of the Amazon River outflow on the geographical distribution of members of Mithracinae, acting as a biogeographical barrier for some species.Universidade Estadual Paulista Instituto de Biociências Departamento de ZoologiaUniversidade Estadual de Londrina Departamento de Biologia Animal e VegetalUniversidade de Taubaté Instituto de Biociências Laboratório de Biologia MarinhaUniversidade Estadual Paulista Instituto de Biociências Departamento de Zoologi

New records of caridean shrimps, Lysmata ankeri and L. cf. intermedia, from southeast coast of Brazil

34Made available in DSpace on 2019-09-11T20:51:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2016Background: The genus Lysmata includes about 40 described species of which at least 12 species occur in the western Atlantic. The present study records the extension of the southern limit of distribution of two species of Lysmata to the coast of São Paulo. Results: A total of 17 and two individual of Lysmata ankeri and Lysmata cf. intermedia were sampled, respectively. Lysmata ankeri were observed inhabiting crevices and natural burrows formed by rocks from 5 to about 15 m depth, while Lysmata cf. intermedia were found living under a large rocky plate from 8 meters depth. Conclusions: These new records improve our knowledge about the geographical distribution of Lysmata ankeri and Lysmata cf. intermedia. The expansion of the geographical distribution of these species may be caused by two different mechanisms of larval dispersal, either natural or anthropogenic. © 2016 The Author(s).De Paiva Barros-Alves, S., Universidade Federal de Sergipe, UFS, Laboratório de Carcinologia, São Cristóvão, Sergipe, BrazilAlves, D.F.R., Universidade Federal de Sergipe, UFS, Laboratório de Carcinologia, São Cristóvão, Sergipe, BrazilHirose, G.L., Universidade Federal de Sergipe, UFS, Laboratório de Carcinologia, São Cristóvão, Sergipe, BrazilCobo, V.J., Universidade de Taubaté, UNITAU, Laboratório de Biologia Marinha, LabBMar, Instituto de Biociências, Taubaté, São Paulo, Brazi

Seasonal variation in population structure and sexual maturity of

Sylviocarcinus pictus is a South American freshwater crab recently recorded for the first time in the Caatinga biome. Our objective was to characterize the population and reproductive biology of S. pictus from the semi-arid northeastern region of Brazil and verify the influence of seasonal environmental changes in this population. The crabs were collected from a stretch of Guaribas River, PI, Brazil, every month between October 2013 and September 2014. The crabs were identified, sexed and the carapace width (CW) was measured. Physiological sexual maturity was determined based on the gonadal development stage. A total of 178 crabs were obtained (111 males and 67 females), with a sex ratio biased towards males 1.66:1. The number of crabs collected was higher in the months of drought. Males and females reach physiological sexual maturity with 36.80 and 34.20 mm of CW, respectively. The occurrence of individuals with developed or developing gonads throughout the study indicates that these crabs reproduce continuously during the year, although recruitment was higher in February and May. Our results indicate that this population uses a reproductive strategy to optimize its reproductive fitness in an intermittent environment.One key finding of this work is that the studied population seems to be well adapted to its harsh semi-arid environment. Even in an intermittent river, Sylviocarcinus pictus, apparently, manages to keep a continuous breeding pattern, also documented for species from temperate regions of the globe

Seasonal variation in population structure and sexual maturity of <i>Sylviocarcinus pictus</i> (Decapoda: Trichodactylidae) in a Neotropical intermittent river

Sylviocarcinus pictus is a South American freshwater crab recently recorded for the first time in the Caatinga biome. Our objective was to characterize the population and reproductive biology of S. pictus from the semi-arid northeastern region of Brazil and verify the influence of seasonal environmental changes in this population. The crabs were collected from a stretch of Guaribas River, PI, Brazil, every month between October 2013 and September 2014. The crabs were identified, sexed and the carapace width (CW) was measured. Physiological sexual maturity was determined based on the gonadal development stage. A total of 178 crabs were obtained (111 males and 67 females), with a sex ratio biased towards males 1.66:1. The number of crabs collected was higher in the months of drought. Males and females reach physiological sexual maturity with 36.80 and 34.20 mm of CW, respectively. The occurrence of individuals with developed or developing gonads throughout the study indicates that these crabs reproduce continuously during the year, although recruitment was higher in February and May. Our results indicate that this population uses a reproductive strategy to optimize its reproductive fitness in an intermittent environment.</jats:p

Population dynamics of the mud crab Panopeus austrobesus Williams, 1983 (Brachyura: Panopeidae) associated with a mussel farm at the southeastern Brazilian coast

Made available in DSpace on 2019-09-11T20:58:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2017Abstract Mussel farms are one of the most important modalities of aquaculture and constitute almost 80% of the total bivalve production in Brazil, representing about 5% of the national production. Brachyuran crabs are common inhabitants of these environments and represent an important link in coastal marine food chains. The aim of this investigation is to describe the population structure of Panopeus austrobesus Williams, 1983 in a Perna perna (Linnaeus, 1758) farm located at the southeastern Brazilian coast. The samplings were carried out in the northeastern coast of São Paulo State. From May 2002 to April 2003, one mussel net was recovered monthly, and all individuals of P. austrobesus were collected. Population size-frequency analysis indicated a unimodal and non-normal distribution. Males were significantly larger than females, and the overall sex ratio significantly skewed from 1:1, female-biased. Recruitment occurred during the entire period, and ovigerous females were found in 11 months. The onset of sexual maturity was estimated around 5 mm cephalothorax width. Mussel farms represent an anthropogenic intervention in the sea landscape, causing environmental changes. However, these structures must allow species introduction, increasing their ecological and geographical distribution, and provide available space and food to establish new populations. This is particularly important for species with small populations, such as P. austrobesus. The results of this study attest the environmental counterpart role of the mussel farms. Once they can support populations, they may also help to reintroduce them into the area and could therefore be used in a consortium generating economic profits and acting as bioremediation tool, assuring the maintenance of the genetic patrimony.[Cobo, Valter José] Universidade de Taubaté, BrazilLima, Daniel José Marcondes] Universidade Estadual Paulista, BrazilCamargo, Flavio de Vasconcelos] Fundação de Ensino e Pesquisa de Itajubá, BrazilAlves, Douglas Fernandes Rodrigues] Universidade Federal de Sergipe, Brazi

First zoeal stage of the crab Domecia acanthophora (Desbonne, in Desbonne & Schramm, 1867) (Decapoda, Brachyura) and revision of the larval morphology of superfamily Trapezioidea

Made available in DSpace on 2019-09-11T20:58:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2016ABSTRACT The morphology of the first zoeal stage of Domecia acanthophora (Desbonne, in Desbonne & Schramm, 1867) was described from laboratory-hatched material obtained from ovigerous females collected at Vitória Island on the southeastern Brazilian coast. We compared the larval morphology (zoea I) of fourteen species of the superfamily Trapezioidea, which Domecia glabra Alcock, 1899 is the only congeneric representative of the species described in this study. The morphological characteristics of the first zoea that distinguish D. acanthophora from D. glabra are: three aesthetascs on the exopod antennule; three pairs of lateral spines on carapace; bilobed basial endite of maxilla, with four plumodenticulate setae on each lobe; and telson furcae distally spinulated. It also provides information that may enhance some phylogenetic hypotheses within Trapezioidea crabs.[Pantaleão, João Alberto Farinelli; Costa, Rogério Caetano da] Universidade Estadual Paulista, BrazilAlves, Douglas Fernandes Rodrigues; Pantaleão, João Alberto Farinelli; Barros-Alves, Samara de P.; Costa, Rogério Caetano da; Cobo, Valter José] Universidade Estadual Paulista, BrazilAlves, Douglas Fernandes Rodrigues; Barros-Alves, Samara de P.] Universidade Federal de Sergipe, BrazilCobo, Valter José] Universidade de Taubaté, Brazi

Ecological distribution and population features of Hexapanopeus paulensis Rathbun, 1930 (Crustacea: Decapoda: Xanthoidea) caught by bottom trawling in the southeastern coast of Brazil: implications for its population structure

ABSTRACT We analyzed the spatio-temporal variations of the abundance, distribution and the population structure of Hexapanopeus paulensis Rathbun, 1930 from the southeastern Brazilian coast. Monthly samples were taken from January 1998 to December 1999 at Ubatumirim, Ubatuba and Mar Virado bays. A total of 1084 individuals were obtained, 76 specimens at Mar Virado, 322 at Ubatuba and 686 at Ubatumirim. It was possible to verify an association between the abundance of H. paulensis and bottom temperature (positive correlation), grain size of sediment and organic matter content (both negatively). This explains the higher number of individuals in the stations nearest to the continent (with higher temperature values and heterogeneous substrate). Juveniles were recorded throughout the study period, constituting 39.5% of the sampled population, which highlights the importance of the region (especially Ubatumirim Bay, due the highest abundance) for the establishment of the species. Only females occupied the largest size classes, which could mean differential mortality between the sexes or growth rate. Nevertheless, further studies should be accomplished to a better comprehension of such difference