Biologia reprodutiva de Macrobrachium olfersii (Wiegman) (Crustacea, Decapoda, Palaemonidae) coletados na Ilha de Santa Catarina, Brasil

Abstract

ABSTRACT. Reproductive biology of Macrobrachium o({ersii (Wiegman) (Crustacea, Decapoda, Palaemonidae) collected at Santa Catarina's lsland, Brazil. The aim of this study is to characterize the reproductive features of Macrobrachium olfersii (Wiegman, 1836) from Santa Catarina' s Island. The animaIs were collected in freshwater streams ofthe Ratones Hidrografic Basin (site A I) and at the Peri's Pond (site A2). In the laboratmy, the procedures of sexual differentiation were canied out to c1assify the individuaIs in males, females or ovigerous females, followed by the detennination oftotal weight (g), quelipod relative weight (g) and totallength (mm). The eggs were removed from the ovigerous females and counled. Sexual malurity and fecundity were analyzed based in the dimensions and number of eggs carried by ovigerous females. The water temperature on lhe capture sites varied from 17 to 29°C throughout lhe months of study. A total of 503 individuaIs were captured, wilh 129 individuaIs from site A I and 374 ll'om site A2 . The mean total size and lenglh was 49.65 mm and 3.79 g for lhe males, 38.75 mm and 1.61 g for lhe females and 36.19 mm and 1.08 g for the ovigerous females. At the sites A I and A2, the individual sexual maturity was reached with 27.3 and 21.2 mm of total length, respectively, while populational sexual maturity was estimated for the 45.0 to 50.0 mm c1ass at site AI and for the 30.0 to 35.0 mm class at site A2. The ovigerous females carried an average of 3464 eggs at site A I, and 1440 eggs at site A2. These reproduclive feature s, presented by M olfersii, show the species' plasticity, which can be associated with environmental variations, contributing to ils reproductive success. KEY WORDS. Macrobrachium olf ersii, fecundity, sexual maturity, environmental condilions Na Ilha de Santa Catarina foram registrados representantes da família Palaemonidae (Rafinesque, 1815), identificadas como Macrobrachium acanthurus

Biologia reprodutiva de Macrobrachium jelskii (Crustacea, Decapoda, Palaemonidae) no Rio São Francisco, Minas Gerais, Brasil

“…E segundo Ammar et al (2001), as variações na estimativa da fecundidade podem ser decorrentes de diferenças no tamanho máximo dos exemplares e das características genéticas próprias das populações de origem. No entanto, fêmeas menores apresentam condições fisiológicas e morfológicas distintas, uma vez que desovam menor número de ovos por apresentarem um reduzido tamanho ovariano e espaço abdominal restrito para a incubação dos mesmos (Clarke, 1993).…”

Estagiamento de embriões de Macrobrachium olfersi (Wiegman) (Crustacea, Palaemonidae) através de critérios morfológicos nos dias embrionários

“…Macrobrachium olfersi é a espécie mais representativa dentre os palemonídeos coletados na Ilha de Santa Catarina, cujas fêmeas alojam seus numerosos ovos em uma câmara incubadora, por um período relativamente curto de tempo (AMMAR et al 2001, NAZARI et al 2003. Tais características, típicas da maioria dos malacostracos, associadas à adaptabilidade da espécie às condições experimentais permitem o acompanhamento e a retirada diária de amostras de ovos viáveis ao longo de todo período de incubação.…”

Distribution and abundance of freshwater decapods in an Atlantic rainforest catchment with a dammed future

“…Decapods, and especially shrimps look to be scarce and present a restricted distribution in Guapiacú river catchment when compared with other coastal catchments (Ammar et al, 2001;Mattos and Oshiro, 2009;Silveira, 1997), but this is difficult to confirm due to differences in sampling techniques. We found species that have different reproductive strategies: Trichodactylidae crabs and M. potiuna shrimp are freshwater specialized species that have the entire life cycle in freshwater, while M. olfersii and M. carcinus are amphidromous (Silveira, 1997) and depend on estuarine brackish water for the development of the first stages of larval growth.…”

“…The knowledge of freshwater decapods in Brazil Atlantic coast has increased during the last decades, especially regarding their taxonomy, distribution (Bond-Buckup and Buckup, 1989;Magalhães, 2003;Magalhães et al, 2005;Mossolin and Mantelatto, 2008;Sampaio et al, 2009;Mossolin et al, 2016;Rocha and Bueno, 2011) and population structure (Ammar et al, 2001;Albertoni et al, 2002;Antunes and Oshiro, 2004;Mossolin and Bueno, 2002;Collins et al, 2006;Mattos and Oshiro, 2009). However, there is a lack of studies assessing effects of stream environmental variables on decapod communities in this area, which restricts our ability to conduct efforts for their conservation.…”