The objective of this study was to provide information on the histological characteristics of the gonads of male and female Armases rubripes crabs, and to try to establish a relationship between the microscopic and macroscopic stages previously identified. Thirty-six crabs were collected by hand between February 2003 and January 2004 in banks of Spartina alterniflora on Sahy Beach in Mangaratiba, Rio de Janeiro state, Brazil. The histological analysis of the ovaries of A. rubripes demonstrated a gradual process of development of the oocytes. According to their cellular characteristics, five types of cells were distinguished: oogonia, oocyte I, oocyte II, oocyte III and oocyte IV. The ovaries showed four stages during gonadal activity: stage I (rudimentary), stage II (developing or maturing), stage III (developed or mature) and stage IV (resting). The results of the histochemical analyses showed that the ovaries vary according to the gonad development stage. The histological aspect of one section of the male gonad was always the same in all of the seminiferous tubules, where the lumen of these tubules always contained spermatozoa and/or spermatids. It was not possible to characterize the three stages of gonad development in the males. This agrees with previous reports in the literature. However, in the females there was a relationship between the gonad stages distinguished macroscopically and the results obtained through the histological and histochemical analysis, due to the presence of different cell types, as well as the lysis process and reabsorption of the oocytes in spent females.Keywords: crab, gonadal development, histochemistry, Sesarmidae. Análise histológica e histoquímica do desenvolvimento gonadal de machos e fêmeas deArmases rubripes (Rathbun, 1897) (Crustacea, Brachyura, Sesarmidae)

ABSTRACT. Populational structure of the sympatric freshwater shrimps Potimirim glabra and Potimirim potimirim (Crustacea, Decapoda, Atyidae) in the Sahy River, Rio de Janeiro, Brazil. The aim of this work was to get some knowledge about the populational structure of the two sympatric freshwater shrimp species, Potimirim glabra (Kingsley, 1878) and Potimirim potimirim (Müller, 1881) in the Sahy River, Mangaratiba, Rio de Janeiro, Brazil. The specimens were sampled monthly from September 1997 to February 1999 by sieving the marginal vegetation, on rocky surface and among litter on river bottom, with 15-minute effort per sampling period. The animals were sorted sexed and their total and cephalothoracic length were measured. A total of 4,889 individuals were collected in Sahy river: 3,281 P. glabra and 1,608 P. potimirim. The sex ratio for all collected individuals was 1:1 for P. glabra and 1:2.3 for P. potimirim. In both populations, five sexual maturity stages were determined and the populations were constituted mainly of adult freshwater shrimps. This study shows the difference between the recruitment of juveniles along these species. The recruitment for P. glabra occurs throughout the year, except in Spring, while P. potimirim was recorded only in Autumn. The seasonal distribution of ovigerous females of P. glabra is similar to P. potimirim, with reproduction on Spring and Summer.KEYWORDS. Atyidae, freshwater shrimps, populational structure, Potimirim, recruitment.Estação de Biologia Marinha, Universidade Federal Rural do Rio de Janeiro, Rua Sereder s/nº, Itacuruçá, Mangaratiba, 23880-000 Rio de Janeiro, Brasil. (giovalverde@yahoo.com.br; oshiro@ufrrj.br) RESUMO. Este trabalho teve por objetivo obter conhecimento sobre a estrutura populacional de dois camarões de água doce simpátricos, Potimirim glabra (Kingsley, 1878) e Potimirim potimirim (Müller, 1881) no rio Sahy, Mangaratiba, Rio de Janeiro, Brasil. Os indivíduos foram coletados mensalmente durante o período de setembro de 1997 a fevereiro de 1999 utilizando-se peneiras, que foram passadas sob a vegetação marginal, superfície de rochas e pequenas poças d'água, num esforço de 15 minutos por coletor. Os animais foram separados quanto ao sexo e mensurados em relação ao comprimento total e do cefalotórax. Um total de 4.889 indivíduos foram coletados no rio Sahy: 3.281 P. glabra e 1.608 P. potimirim. A razão sexual observada foi de 1:1 para P. glabra e 1:2,3 para P. potimirim. Em ambas populações, cinco estágios de maturidade sexual foram determinados, sendo as populações constituídas principalmente por camarões adultos. O recrutamento de juvenis apresentou diferenças em ambas as espécies. O recrutamento de P. glabra ocorreu durante todo o período de estudo, exceto na primavera, enquanto que P. potimirim foi registrado somente no outono. A distribuição sazonal de fêmeas ovígeras de P. glabra é similar ao de P. potimirim, com reprodução na primavera e no verão. PALAVRAS-CHAVE.Atyidae, camarões de água doce, estrutura populacional, Potimirim, recrutamento.

Iheringia, Sér. Zool., Porto Alegre, 96(1):47-52, 30 de março de 2006 Reproductive biology of the sesarmid crab Armases rubripes (Decapoda, Brachyura)... ABSTRACT. The aim of this work was to gain knowledge about reproductive biology of the crab Armases rubripes (Rathbun, 1897) from an estuarine area of the Sepetiba Bay. Samples were taken monthly from February 2003 to January 2004 in the Sahy River estuary (22º56'S; 44º01'W), Rio de Janeiro, Brazil. The crabs were collected by hand during 15-minute catch-effort sessions conducted by two people. In the laboratory, the specimens were separated by sex, carapace width was measured and gonadal stage was checked macroscopically. A total of 830 individuals were caught -304 males, 373 females (60 ovigerous females) and 153 juveniles. The ovigerous females were found almost year-round, except in November and April, showing a continuous reproductive period. They presented a size range from 8.2 to 15.0 mm carapace width (12.1 ± 1.7 mm). Color and macroscopical aspects determined five gonadal stages for males and females (immature, rudimentary, intermediary, developed and resting). First sexual maturity was estimated at 6.5 mm of carapace width for males and 8.1 mm for females. Individual fecundity varied from 200 to 11,460 eggs (4,458 ± 2,739 eggs). Mean egg size was 0.248 ± 0.026 mm, varying from 0.213 to 0.333 mm, while the volume ranged from 0.0051 to 0.0188 mm 3 (0.0082 ± 0.0029 mm 3 ). Reproductive biology of the sesarmid crab KEYWORDS.Crab, Sesarmidae, fecundity, reproduction, sexual maturity. Crustaceans exhibit various patterns of life history and reproductive strategies, mainly when habitat is considered. According to MANTELATTO & FRANSOZO (1997), fecundity is an important parameter in determining the reproductive potential of a crustacean species and/or of stock size of a population. GONZÁLEZ-GURRIARÁN & FREIRE (1985) related the importance of sexual maturity for estimating the puberty molt for the examination of external morphological modifications and gonads development.The sesarmid crab Armases rubripes (Rathbun, 1897) is a tropical and subtropical species usually found in salt marshes and estuaries of Central and South America (CAPÍTOLI et al., 1977), widely distributed from Nicaragua to Rio de la Plata, between Uruguay and Argentina (MELO, 1996).According to CAPÍTOLI et al. (1977), FISCHER et al. (1997) and TEIXEIRA & SÁ (1998), these small crabs feed on vegetable debris, mainly roots and stems of Spartina sp. (Poaceae), living inside self-built burrows in muddy substrates or between bromeliad axils. Aspects concerning to biology of this species are restricted to a few studies. CAPÍTOLI et al. (1977) studied this species in the estuarine region of Lagoa dos Patos, Rio Grande do Sul (Brazil); FISCHER et al. (1997) As a contribution to the knowledge of this crustacean, some aspects of the reproductive biology of A. rubripes from an estuarine area were examined (e.g. sexual maturity, breeding period, molting, fecundity and eggs size). After their collectio...

Objetivou-se analisar a maturidade sexual de Armases rubripes (Rathbun, 1897) em três diferentes ambientes (rio, praia arenosa e manguezal) no sudeste do Brasil. Os caranguejos foram coletados mensalmente de julho/2002 a fevereiro/2004, utilizando-se peneiras no Rio Sahy durante as marés altas e, manualmente, na praia e no manguezal, durante as marés baixas. Os animais foram capturados por dois coletores num esforço de 15 minutos por estação de coleta. No laboratório, os exemplares foram separados por sexo e mensurados em relação a largura da carapaça, do abdome e comprimento do gonopódio. As gônadas, gonopódios e o abdome foram analisados segundo sua forma e seu aspecto. Um total de 4.051 indivíduos foram amostrados (1.067 machos, 1.563 fêmeas e 1.421 juvenis). Foram determinados cinco morfotipos: juvenis, machos imaturos, fêmeas imaturas, machos maduros e fêmeas maduras. O início da maturidade sexual fisiológica e morfológica ocorreu de forma assíncrona, com machos produzindo gametas mais cedo que as fêmeas. O tamanho da primeira maturidade sexual apresentou diferença significativa entre os ambientes analisados, exceção observada para o manguezal. Os indivíduos obtidos no manguezal apresentaram menores tamanhos para o início da maturidade sexual. Embora, estimados os tamanhos da maturidade sexual morfológica de machos e fêmeas, a análise do crescimento alométrico foi inadequado para a espécie.

ABSTRACT. T he reprodu clive aspects of lhe freshwaler sh rimp Palaem oTl palldaliJormis (S limpson) (Cruslacea, Decapoda, Palaemonidae) from Sahy Rive r, Mangaratiba, Rio de Janeiro, Brazil. The reprodllctive aspects of the fres hwater shri mp Palaellloll pandaliformis (Stimpson, 187 1) were tudied fro m March, 1998 to February, 1999. Monthly, samples were collected wilh sives, on lhe ri ver edge, under lhe edging vegetation or in small pools. At lhe laboratory, shri mps were sexed and measured in their totallenght, From the tip ofthe rostrllm to lhe oFtelson with precision callipters. The ovigerous shrim ps were separated and counted fo r fec llndity determination. The eggs diameter was measured wi th calibrated tereomicroscope. A total of 872 were collected among which, 46% female, 29% male and 25 % juvenil. The sex ratio was I : 1.57. Ovigerolls fe males were present dllring ali seasons, bllt the reprodllctive peak accllrred in Sp ring. The ov igero lls female showed total lenght from 23.0 to 39.6 mm . The mean fecund ity was 137 eggs per female, with a minimum of 40 eggs and a max imum of 270 eggs. The fir t sexual mat uration probably OCCllr at 23 .0 mm total lenght. The mean diameter os the eggs size was 0. ( 1996, 1999), es tud a ra m os as pectos reprod u tivos da es pécie, res pe ctiva m e nte nos Es tad os d e P e rn a mb uco e S a nta Catarina.Este trabalho proc u ro u a m p liar as info rm ações sobre a esp éc ie e contribui r pa ra o conhecimento de s ua bi o logia re pro dutiv a no Ri o S a hy , M a n ga ra tib a, Es ta d o do Rio de Janeiro.