A new species of the sea pen genus Scytalium Herklots, 1858, is proposed based on the morphological and molecular study of a colony collected during the Océano Profundo 2018 cruise to the Caribbean Sea (NW Atlantic). The new species, Scytalium herklotsi sp. nov., is characterized by its well-developed and overlapping polyp leaves (up to 68 mm in length and 27 mm in width), the presence of eight spiculated large digitiform processes at the distal part of the basal portion of autozooids, the axis rounded in cross section, the numerous siphonozooids in a continuous band of 3–6 rows along the latero-dorsal area of the rachis, and up to 3 rows between contiguous polyp leaves, among other features. An additional unrecorded type of sclerites is reported from the pharynx of autozooids, probably also present in other species of the genus. Scytalium herklotsi sp. nov. is the first species of the genus recorded so far from the Atlantic Ocean, all other described species being Indo-West Pacific. The new species is also the deepest record of a Scytalium species (ca 500 m in depth); the previous published records range from 10 to 206 m in depth. A molecular comparison based on a set of concatenated sequences of four markers (three mitochondrial genes (mtMutS, ND2, and Cox1) and a nuclear segment (28S)) relates the new species to other published sequences attributed to Scytalium species, within the named Clade II of previous general phylogenetic studies on the octocoral Order Pennatulacea.

海笔属Scytalium Herklots 的一个新物种是1858 年，是基于对2018 年 Océano Profundo加勒比海（西北大西洋）航行期间收集的一个殖民地的形态学和分子研究提出的。新物种Scytalium herklotsisp. 11 月，其特征在于其发育良好且重叠的息肉叶（长达 68 毫米，宽达 27 毫米），自体动物基部远端有八个带毛刺的大指状突起，轴为圆形在横截面中，沿着轴的侧背区域呈 3-6 行连续带状的众多虹吸虫，在连续息肉叶之间最多 3 行，以及其他特征。据报道，自体动物的咽部有另一种未记录的硬骨，可能也存在于该属的其他物种中。Scytalium herklotsi sp. 十一月 是迄今为止从大西洋记录到的该属的第一个物种，所有其他描述的物种都是印度-西太平洋。这个新物种也是Scytalium的最深记录物种（深度约 500 m）；先前公布的记录深度为 10 至 206 m。基于一组的四个标记（3个线粒体基因（连续序列的分子比较mtMutS，ND2，和COX1）和核段（28S））涉及新的物种归因于其他已发表的序列Scytalium物种，已命名的进化枝内以前对八珊瑚目五角星的一般系统发育研究的 II。