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首页> 外文期刊>Marine biology >Reproductive cycle of the endemic cassiduloid Cassidulus mitis (Echinoidea : Cassiduloida) on the Brazilian coast
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Reproductive cycle of the endemic cassiduloid Cassidulus mitis (Echinoidea : Cassiduloida) on the Brazilian coast

机译：巴西沿海地区地方性assi虫科Cassidulus mitis（Echinoidea：Cassiduloida）的繁殖周期

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Cassidulus mitis Krau, 1954 is an endemic species from Rio de Janeiro, Brazil. To study the reproductive cycle of this species, samples were collected at Praia Vermelha, in Guanabara Bay, from Octo er 1998 to April 2000. The sex ratio for C. mitis was 1: 1, and reproduction occurred throughout the year. The gonadal index of males was greater than that of females. Five gametogenic stages were identified in males: early growth, premature, mature, partially spawned and early growth with a partially spawned stage. There were no spent or recovery stages such as those seen in females. Females had six gametogenic stages: recovery, early growth, premature, mature, partially spawned and spent stage; there was no early growth with a partially spawned stage as there was in males. The mean oocyte diameter was 382 mum (SD=49 mum), and the mean number of juveniles per female was 100 individuals (SD=108). The anterior gonads were frequently smaller than the posterior ones, and there were differences in the gametogenic stages between the anterior and posterior gonads. First sexual maturation occurred in individuals with a diameter of 17 mm. The intestinal wet weight was two- to threefold higher than the test wet weight. This may indicate that C. mitis uses its intestine as a "weight belt" to avoid displacement from the substratum.
机译：Cassidulus mitis Krau，1954年是巴西里约热内卢的特有物种。为了研究该物种的繁殖周期，从1998年10月至2000年4月在瓜纳巴拉湾的Praia Vermelha采集了样本。棉铃虫的性别比为1：1，并且全年都有繁殖。男性的性腺指数高于女性。在雄性中鉴定出五个配子发生阶段：早期生长，早产，成熟，部分产卵和具有部分产卵阶段的早期生长。没有女性经历过的花费或恢复阶段。雌性有六个致配子阶段：恢复，早期生长，早产，成熟，部分产卵和花粉阶段。没有早期生长，部分产卵期与雄性一样。卵母细胞平均直径为382微米（SD = 49微米），每名女性的平均少年数量为100个个体（SD = 108）。前性腺通常比后性腺小，并且前性腺和后性腺的配子发生阶段有所不同。第一次性成熟发生在直径17毫米的个体中。肠的湿重比测试的湿重高两倍至三倍。这可能表明毛状衣原体将其肠用作“重带”，以避免从基底移位。

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