Instituto Politécnico Nacional, Centro Interdisciplinario de Ciencias Marinas, La Paz, Mexico.
Instituto de Ciências Biológicas, Sector Morfologia, Universidade Federal de Rio Grande, Rio Grande, Brazil.
J Fish Biol. 2021 Mar;98(3):791-802. doi: 10.1111/jfb.14627. Epub 2020 Dec 15.
The Rasptail skate Rostroraja velezi is commercially exploited in artisanal elasmobranch fisheries along the west coast of Baja California Sur, Mexico, but information on its life history is limited. This study aimed to investigate the reproductive biology of R. velezi. A total of 105 specimens were caught from April 2008 to May 2012, including the largest reported specimen with 121 cm total length, 96 cm disc width (D ). Females attained larger sizes than males. Males and females presented functional gonads. There was an asymmetry in the testes of males, with the left testis being larger. Histological analysis of the reproductive biology of R. velezi was performed here for the first time. The presence of sperm storage in females and spermatogenic development beginning at the first stages of maturity in males was recorded. It was possible to identify the development of secretions in the club, baffle and terminal zone of the oviducal gland. D at maturity, defined as the D at which 50% of the population is mature, was estimated at 68-72 cm for females and 65.1 cm for males. Egg-bearing females caught in April and May presented one egg capsule per uterus. Furthermore, a description of the egg capsule of R. velezi is provided. Elucidating the reproductive cycle, the type of reproductive strategies, and the fecundity of R. velezi will allow us to understand the impact of fisheries on this species.
拟庸棘鲛是墨西哥下加利福尼亚湾西部沿岸的小型手工捕捞渔业中被商业开发的鲨鱼物种之一,但有关其生活史的信息有限。本研究旨在调查拟庸棘鲛的生殖生物学。2008 年 4 月至 2012 年 5 月期间共捕获了 105 个标本,包括报告的最大标本,全长 121 厘米,盘宽 96 厘米(D)。雌性比雄性体型更大。雌雄两性均具有功能性性腺。雄性的睾丸存在不对称性,左侧睾丸较大。本文首次对拟庸棘鲛的生殖生物学进行了组织学分析。记录了雌性的精子储存和雄性在成熟的第一阶段开始精子发生的现象。可以识别出输卵管的棒状部、隔板部和终末部的分泌物的发育情况。成熟的 D 值,定义为种群中有 50%成熟的 D 值,估计雌性为 68-72 厘米,雄性为 65.1 厘米。4 月和 5 月捕获的怀卵雌性每个子宫内有一个卵囊。此外,还提供了拟庸棘鲛卵囊的描述。阐明拟庸棘鲛的生殖周期、生殖策略类型和繁殖力,将有助于我们了解渔业对该物种的影响。