Amiantis purpurata is the dominant clam of shallow subtidal soft bottom communities in Buenos Aires province where it is a major prey item of economically important fish and gastropods as well as anemones. Despite its significant role in the benthic food web, there are few studies dealing with the population biology of this species. Growth, age, mortality, and production along with reproductive patterns and size at first maturity of A. purpurata were investigated at Mar del Plata (38 ºS) area and compared with a population at the southernmost point of distribution, the only other studied population (42 ºS). Early growth was empirically documented for the first time for this species by following a newly recruited cohort throughout the first two years of growth. This allowed for the size and age at first maturity to be accurately determined and provided early growth data for models, which are often difficult to obtain. Larger asymptotic size and quicker rates were reached at lower latitudes. Reproduction followed patterns similar to other temperate venerid bivalve populations with a more extended period of spawning observed at Mar del Plata. The studied population shows relatively high growth rates, achieves sexual maturity at approximately two years of age, and successfully recruits in this area, which was not observed in the other studied population for over 15 years. The environmental conditions in this area are likely more favorable than that of the southernmost population which shows low growth rates and no successful recruitment.

中文翻译：

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紫蛤Amiantis purpurata的种群动态，生长，生产和繁殖

Amiantis purpurata是布宜诺斯艾利斯省浅潮下软底群落的主要蛤类，那里是经济上重要的鱼类和腹足动物以及海葵的主要猎物。尽管它在底栖食物网中起着重要作用，但很少有研究涉及该物种的种群生物学。紫红色紫菜初生时的生长，年龄，死亡率和产量以及繁殖方式和大小在马德普拉塔（38ºS）区域进行了调查，并与分布最南端的人口进行了比较，这是其他唯一研究的人口（42ºS）。通过在生长的前两年中新招募的队列研究，首次有经验地记录了该物种的早期生长。这样就可以准确确定首次到期的大小和年龄，并提供模型的早期增长数据，而这些数据通常很难获得。在较低的纬度上，可以达到较大的渐近大小和更快的速率。繁殖遵循与其他温带双壳类双壳类种群相似的模式，在马德普拉塔观察到产卵期延长了。被研究的人群显示出较高的增长率，大约在两岁时达到性成熟，并成功地在该地区招募新兵，这在15年来的其他研究人群中均未发现。该地区的环境条件可能比最南部人口的环境条件更为有利，因为南部地区的人口增长率低且没有成功招募。