Gametogenesis in Madracis decactis Lyman, 1859 (Cnidaria, Scleractinia) from Ilha Grande Bay (Rio de Janeiro), southeastern Brazil

Abstract

Collections were made every two months in Ilha Grande Bay, Rio de Janeiro, for 21 months (August/2004-May/2006) to study the gametogenesis of Madracis decactis Lyman, 1859. A total of 1800 polyps were examined using standard histological techniques. Madracis decactis is a hermaphroditic species whose male and female gametes develop within different mesenteries. Oogenesis begins in October, while spermatogenesis begins at the end of February, both reaching maturity at the end of April. The peak of reproductive activity occurred between February and April, when all the polyps were fertile, containing mainly stage III oocytes. Examination of fertile polyps indicated the simultaneous presence of stages I, II and III for oogenesis and I, II, III and IV for spermatogenesis. No embryos or planulae were observed in the histological sections. The gametes or planulae spawning may occur between April and May.<br>Coletas foram feitas a cada dois meses na Baía de Ilha Grande, Rio de Janeiro, durante 21 meses (agosto/2004 - maio/2006) para estudar a gametogênese de Madracis decactis Lyman, 1859. Um total de 1800 pólipos foram examinados através de técnicas histológicas padrão. M. decactis é uma espécie hermafrodita, cujos gametas masculinos e femininos se desenvolvem em mesentérios diferentes. A ovogênese iniciou em outubro, e a espermatogênese no final de fevereiro, ambas alcançando maturidade no final do mês de abril. O pico da atividade reprodutiva ocorreu entre fevereiro e abril quando todos os pólipos estavam férteis contendo, principalmente, ovócitos no estágio III de maturação. O exame dos pólipos férteis indicou a presença simultânea dos estágios de desenvolvimento I, II e III para a ovogênese e dos estágios I, II, III e IV para a espermatogênese. Não foram encontrados embriões ou plânulas nos cortes histológicos. Os dados indicam que a liberação dos gametas ou plânulas deve ocorrer, provavelmente, entre os meses de abril e maio

Life history and reproductive dynamics of the cryptogenic calcareous sponge Sycettusa hastifera (Porifera, Calcarea) living in tropical rocky shores

“…The reproduction of S. hastifera was not statistically related to seawater temperature in Arraial do Cabo, contrasting with previous observations for many species of Porifera and other marine invertebrates (e.g. Giese & Pearse, 1974; Fromont, 1994; Castro & Pires, 2006; Ettinger-Epstein et al ., 2007; Abdo et al , 2008; Riesgo & Maldonado, 2008; Muramatsu & Silveira, 2008; Lanna et al , 2015). It may be argued that the variation in the water temperature in Arraial do Cabo (ΔT = 7°C) during this study was not sufficient to influence the reproductive activity of S. hastifera , as in other locations this variation is of greater order (e.g.…”

Morphological and genetic divergence between Mediterranean and Caribbean populations of Madracis pharensis (Heller 1868) (Scleractinia, Pocilloporidae): too much for one species?

“…To date, no formal revision has been undertaken. However, much progress has been made in the current knowledge on the biology, ecology and systematics of the shallow water hermatypic Madracis species from the Caribbean (Diekmann et al 2001;Vermeij & Bak 2002a, b;Vermeij et al 2001Vermeij et al , 2002Vermeij et al , 2003aVermeij et al , b, c, 2004Kaandorp et al 2003Kaandorp et al , 2005Vermeij & Sandin 2006;Frade et al 2008aFrade et al , b, c, 2010Filatov et al 2013) and Brazil (Muramatsu & Lang da Silveira 2008;Neves & Johnsson 2009;Capel et al 2012). Outside of the Western Atlantic, the studies on deep and shallow water Madracis species deal mainly with their taxonomy and occurrence (Veron & Pichon 1976;Cairns 1991Cairns , 1994Cairns , 1999Cairns & Zibrowius 1997;Veron 2000;Zibrowius et al 2017), less frequently with aspects of their biology and ecology (Laborel & Vacelet 1958;Zibrowius 1980;Morri et al 2000;Özalp & Alparslan 2015).…”