The marine aquarium industry has grown significantly and so has marine ornamental fish aquaculture. The main species targeted by commercial aquaculture are clownfish, dottybacks, gobies, and blennies. However, the limited knowledge available for the reproductive biology of several fish species hinders production, especially for blennies. Therefore, this study investigated whether two mass‐produced blenniids, Meiacanthus nigrolineatus and Meiacanthus smithi, are gonochorists and display caudal fin sexual dimorphism. For this purpose, gonadal samples and morphometric data were collected from specimens of both species kept in captivity for 6 months. Histological preparations of the whole individuals or their gonads were performed and analyzed. Results show that sex ratio does not differ from 1:1 and that gonadal development was similar to other blenniids. No evidence of sexual reversion or simultaneous hermaphroditism was found in the first 8 months of development, suggesting that both species are gonochoric. Differences in the length of upper and lower rays in the caudal fin were not detected for M. smithi, but M. nigrolineatus male individuals displayed significantly longer upper and lower rays, confirming it as a dimorphic trait for this species. The identification of the sexual pattern and sexually dimorphic traits may aid in broodstock pairing for M. nigrolineatus blennies, improving its aquaculture production and perhaps reducing some of the pressure on wild stocks.

中文翻译：

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在商业化水产养殖的Meiacanthus blennies（Teleostei：Blenniidae）中，性模式和尾鳍作为性二态性状

海洋水族馆业显着增长，海洋观赏鱼水产养殖业也迅速发展。商业水产养殖的主要目标物种是小丑鱼、,、虾虎鱼和鱼。但是，几种鱼类生殖生物学的可用知识有限，阻碍了其生产，特别是对鱼皮的生产。因此，本研究调查了是否有两个大量生产的夹竹鱼，Meiacanthus nigrolineatus和Meiacanthus smithi，是性腺刺激者，并表现出尾鳍性二态性。为此，从被关押了6个月的两个物种的标本中收集了性腺样品和形态数据。进行并分析了整个个体或其性腺的组织学准备。结果表明，性别比例与1：1并无差异，性腺发育与其他宽吻鳄相似。在发育的前8个月中没有发现性逆转或同时发生雌雄同体的迹象，表明这两个物种均为淋病性。对于史密斯氏菌，未检测到尾鳍上，下尾鳍的射线长度的差异，但对尼古拉菌而言雄性个体显示出明显更长的上下射线，证实了它是该物种的双态性状。对性模式和性二态性状的识别可能有助于黑腹线虫（M. nigrolineatus brnnies）亲鱼配对，提高其水产养殖产量，并可能减轻对野生种群的一些压力。