Huang Mian, Huang Yong, Xu Kuidong
Department of Marine Organism Taxonomy and phylogeny, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China University of Chinese Academy of Science, Beijing 100049, China.
Zootaxa. 2019 Aug 15;4657(1):zootaxa.4657.1.8. doi: 10.11646/zootaxa.4657.1.8.
A new species of the genus Thalassironus de Man, 1889, which was discovered from marine sediments in the South China Sea, is described here as Thalassironus filiformis sp. nov. The new species is characterized by having short outer labial setae and cephalic setae of equal length, long filiform tail, buccal cavity with three anterior teeth and three additional teeth just posterior to amphideal fovea, male with a segmented midventral precloacal seta, spicules double curved, slender with ventral ala. It is very similar to Thalassironus lynnae Keppner, 1987, but can be differentiated from the latter species by much shorter cephalic setae (8 μm vs 14-16 μm), longer tail (772-780 μm vs 300-506 μm), longer spicules (67-68 μm vs 35-40 μm), smaller value of de Man ratio "a" (66 vs 99.7-102) and different structure of spicules. An updated dichotomous key to all known species of Thalassironus is provided.
本文描述了一种于1889年被发现的新物种——丝状海栖线虫（Thalassironus filiformis sp. nov.），它是从中国南海的海洋沉积物中发现的。该新物种的特征为具有短的外侧唇刚毛和等长的头部刚毛、长丝状尾巴、带有三颗前齿以及在双凹形感器后方还有三颗额外牙齿的口腔、雄性具有分段的腹中线泄殖腔前刚毛、双曲形交合刺、带有腹翼的细长交合刺。它与1987年的林氏海栖线虫（Thalassironus lynnae）非常相似，但可通过更短的头部刚毛（8微米对14 - 16微米）、更长的尾巴（772 - 780微米对300 - 506微米）、更长的交合刺（67 - 68微米对35 - 40微米）、更小的德曼比率“a”值（66对99.7 - 102）以及不同的交合刺结构与后一物种区分开来。本文还提供了一份更新后的丝状海栖线虫所有已知物种的检索表。
