Population biology of Uca mordax (Smith, 1870) (Crustacea, Decapoda, Ocypodidae) from the southeastern coast of Brazil

Abstract

The population biology of the fiddler crab Uca mordax (Smith, 1870) was investigated in an estuarinemangrove from the southeastern coast of Brazil. Samplings were monthly performed by 2 collectors for30 min. using the technique of capture per unit effort during low tide periods. The allometric techniquewas used to determine crab size at sexual maturity (males and females). Thus, specimens were classified into juveniles and adults according to their size at sexual maturity for each sex. The specimens weredistributed into size classes. Recruitment was based on the juvenile frequency and the reproduction peakin ovigerous females. The median size of males was 15.9 ± 2.7 mm carapace width (CW) (n = 557) andthat of females, 14.6 ± 2.8 mm CW (n = 528). At sexual maturity, size of crabs was 11.9 mm CW formales and 11.5 mm CW for females. Juveniles were found throughout the year but more frequently inthe winter and autumn. Sex ratio did not differ among seasons, except during the summer (p < 0.05).As regards sex ratio per size class, females predominated in the fi rst size classes. Reproduction peakwas observed in the summer. In short, the population biology of U. mordax was similar to that of mostbroad-front fi ddler crab species.

Population biology and relative growth of the crab Minuca mordax (Smith, 1870) (Crustacea, Decapoda, Ocypodidae) in the Igaraçu River, Parnaíba, state of Piauí, Brazil

“…In other studies with Minuca crabs, males also reached the morphological sexual maturity with superior size to of females (MASUNARI; SWIECH-AYOUB, 2003;MASUNARI;DISSENHA, 2005;MASUNARI et al, 2005;CASTIGLIONI et al, 2006;SOARES-GOMES, 2008;PRALON;NEGREIROS-FRANSOZO, 2008;FRANSOZO et al, 2009). The morphological sexual maturity to M. mordax was also determined by other researchers in other regions of Brazil, with results similar to those obtained in this study.…”

POPULATION BIOLOGY OF Panopeus lacustris DESBONNE 1867 ( BRACHYURA: PANOPEIDAE ) IN PIAUÍ COASTAL, BRAZIL

“…The growth of gonopodium showed isometry in the juvenile phase and negative allometry after sexual maturity. In Eriphia gonagra (Góes & Fransozo, 1997), Uca rapax (Castiglioni & Negreiros-Fransozo, 2004), Mithrax tortugae (Cobo & Alves, 2009), Uca mordax (Fransozo et al, 2009), Uca thayeri (Araújo et al, 2012), juvenile also showed allometric growth in a higher proportion as compared to adults. The greater growth in the juvenile phase, observed in P. lacustris, may reflect the need for pre-adults to reach sexual maturity, to change the size of characters that allow mating (Fonteles-Filho, 2011).…”

Temporal analysis of the weight/carapace width relationship and the condition factor in Uca mordax (Smith, 1870) (Crustacea, Decapoda, Ocypodidae) in the Igaraçu River, Parnaíba, PI, Brazil

“…Populations of iddler crabs have attracted the interest of the scientiic community. In Brazil, their population biology has been studied in the states of Ceará (BEZERRA; MATTHEWS- CASCON, 2006;2007), São Paulo (RIEGER, 1998;COLPO;BENETTI et al, 2007;2008;FRANSOZO et al, 2009), Rio de Janeiro (CASTIGLIONI et al, 2006), Paraná (DI BENEDETTO;MASUNARI, 2009) and Pará (SIMITH et al, 2014), their relative growth has been studied in Santa Catarina SWIECH-AYOUB, 2003), Paraná , São Paulo (BENETTI; CARDOSO; and Rio de Janeiro (PRALON;NEGREIROS-FRANSOZO, 2008), and their diversity and distribution has also been studied (ARAÚJO et al, 2014).…”