Abstract

We analyzed the reproductive cycle of females of the palaemonid shrimp Macrobrachium tenellum (Smith, 1871) collected in the Ameca River, between the Jalisco and Nayarit states, Mexico. We studied the seasonal occurrence of ovigerous females during the year, their relationship with abiotic factors, and the size of the first sexual maturity. The study included 7,100 specimens of M. tenellum, of which 2,791 (39.3%) were males, 3,559 (50.1%) females, and 750 undifferentiated (10.6%). The sex ratio of the total (male-female) population differed significantly from the expected 1:1 with more females. A total of 309 females carried eggs (8.7% of all collected females). Ovigerous females, which were collected in three of the four sampling sites, were found almost year-round (with the exception of March and December), and their number showed a significant positive correlation with water temperature and rainfall. The size of first maturity (TL_50%) for all collected females was 55.7 mm total length (TL), ranging from 64.3 mm TL to 42.7 mm TL. The results revealed that the population of M. tenellum in the Ameca River has a continuous reproductive period associated with the rainy season and increasing water temperature.

中文翻译：

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墨西哥淡水虾Macrobrachium tenellum（Smith，1871）（十足目：Caridea：Palaemonidae）的生殖生物学

摘要

我们分析了收集在墨西哥哈利斯科州和纳亚里特州之间的阿美卡河中的ala虾虾Macrobrachium tenellum（史密斯，1871年）的雌性繁殖周期。我们研究了一年中雌雄同体的季节性发生，它们与非生物因素的关系以及初次性成熟的大小。该研究共纳入7100个标本M.孢，其中男性2,791（39.3％），女性3,559（50.1％），未分化的750（10.6％）。总人口（男性-女性）的性别比与预期的1：1显着不同，女性更多。共有309名雌性携带卵（占所有收集雌性的8.7％）。在四个采样点中的三个采样点采集的雌雄异体雌虫几乎全年都被发现（3月和12月除外），其数量与水温和降雨量呈显着正相关。所有收集的雌性的首次成熟大小（TL _50％）为55.7毫米总长度（TL），范围从64.3毫米TL到42.7毫米TL。结果显示，M。tenellum的种群 阿梅卡河中的雨季与雨季和水温升高相关，具有连续的繁殖期。