The annual reproductive cycle comprises steady gametogenic activities that synchronize gonadal maturation and spawning rhythms, which are important for aquatic organisms including marine echinoderms (Echinodermata, Echinoidea). In this study, we report the annual reproductive cycle, gonadal development, and changes in nutritive phagocytes (NPs, which accumulate nutrients in germ cells) in relation to gametogenesis of the Atlantic sea urchin (Arbacia punctulata, an edible echinoid) in the Gulf of Mexico. Monthly changes in gonadal development and maturation were observed morphologically and histologically. We calculated gonadosomatic index (GSI) and compared the stages of gonadal development in order to determine the NPs index, and characteristics of germ cells (eggs and sperm) during the annual reproductive cycle. According to GSI and histological analyses, gametogenic activities were classified into four stages of both sexes: mature (June–August), spent (September–November), recovery (December–March), and growing (April–May). The GSI values in both sexes were high during summer months. In males, testicular lobules were densely packed with sperm from June to August. In females, however, mature eggs first appeared in some ovaries in May, numerically increased from June to July, and decreased in August. During gametogenesis, on the other hand, NPs in both testes and ovaries were depleted from June to August. Collectively, our results suggest that the Atlantic sea urchin spawns during summer months in the Gulf of Mexico. This is the first report, to the best of our knowledge, on gonadal development and changes in NPs during the annual reproductive cycle of any Arbacia species in the Gulf of Mexico.

一年一度的生殖周期包括稳定的配子发生活动，使性腺成熟和产卵节律同步，这对于包括海洋棘皮动物（棘皮动物，棘皮动物）在内的水生生物都很重要。在这项研究中，我们报告了与大西洋海胆（Arbacia punctulata）的配子发生相关的年度生殖周期，性腺发育和营养性吞噬细胞（NP，在生殖细胞中积累营养）的变化。墨西哥湾中的可食用类胆碱）。形态和组织学观察到性腺发育和成熟的每月变化。我们计算了性腺体指数（GSI），并比较了性腺发育的各个阶段，以确定NPs指数以及每年生殖周期中生殖细胞（卵和精子）的特征。根据GSI和组织学分析，配子发生活动分为两个阶段：成熟期（6月至8月），花粉期（9月至11月），恢复期（12月至3月）和成长期（4月至5月）。夏季，男女两性的GSI值均较高。在男性中，从六月到八月，睾丸小叶充满了精子。然而，在雌性中，成熟卵首先出现在5月的一些卵巢中，从6月到7月在数量上增加，8月减少。另一方面，在配子发生期间，睾丸和卵巢中的NP都在6月至8月间耗尽。总的来说，我们的结果表明，大西洋海胆在夏季出现在墨西哥湾。据我们所知，这是关于任何生殖器的年度生殖周期中性腺发育和NP变化的第一份报告。墨西哥湾的烟草属物种。