Moscow State University, 119991, Moscow, Russia.
Shirshov Institute of Oceanology, Russian Academy of Sciences, 117218, Moscow, Russia.
Dokl Biol Sci. 2021 Sep;500(1):149-152. doi: 10.1134/S0012496621050033. Epub 2021 Nov 3.
Deep-sea hemichordates Torquaratoridae gen. sp. reach high abundance up to 12 spec. m at the depths of 1830-2130 m on the slope of the Volcanologists Massif in the south-western part of the Bering Sea, dominating in the benthic community at these depths. Their abundance exceeds by two orders the values recorded earlier. In order to clarify this phenomenon, we examined the gut contents of Torquaratoridae gen. sp. The detritus particles and frustules of planktonic diatoms Thalassiosira, Coscinodiscus, Actinocyclus, Chaetoceros, Neodenticula, and Grammatophora were the most common in the gut, as well as the remains of skeletons of benthic invertebrates with little admixture of mineral particles. According to obtained data, Torquaratoridae gen. sp. are mobile deposit feeders with high selectivity to fresh phytodetritus, able to compete with holothurians occupying similar trophic niche. Unusually high abundance of acorn worms is apparently related to high organic matter flux to the seafloor as a result of spring phytoplankton bloom in the surface water layer of the Bering Sea.
深海肠纽虫科（Torquaratoridae）的一个新种在白令海西南部的火山群斜坡上，深度为 1830-2130 米处的海底达到了高达 12 种/米的高丰度，在这些深度的底栖生物群落中占主导地位。它们的丰度超过了之前记录的两个数量级。为了阐明这一现象，我们研究了肠纽虫科的肠道内容物。肠道内容物中最常见的是碎屑颗粒和浮游硅藻的壳，如 Thalassiosira、Coscinodiscus、Actinocyclus、Chaetoceros、Neodenticula 和 Grammatophora，以及底栖无脊椎动物骨骼的残骸，几乎没有矿物质颗粒的混合物。根据获得的数据，肠纽虫科是具有高度选择性的移动沉积物食者，对新鲜的植物碎屑有很高的选择性，能够与占据类似营养生态位的海参竞争。短尾纽虫异常高的丰度显然与白令海表层水层春季浮游植物爆发导致的大量有机物质向海底输送有关。
