Deep-sea cephalopods are important in the bathyal ecosystems in terms of both abundance and diversity, but are seriously understudied. One of the most intriguing groups among the deep-sea cephalopods are Cirrata, relatively primitive octopods. Opisthoteuthis is the largest genus among the Cirrata. The least studied species of Opisthoteuthis in the Atlantic, Opisthoteuthis borealis Collins, 2005 was known from nine specimens only prior to our study, and nothing was described about its biology. Four males, all larger than the previously known maximum size (mantle length 78–96 mm cf. 75 mm), are described and COI sequence of the species provided to ease the identification of the Atlantic Opisthoteuthis. Our findings expand the known geographical (North Atlantic from 60° N northward and up to the Davis and Denmark Straits and the Iceland–Faroe Ridge), depth (878–1321 m) and temperature (3.0–3.6 °C) ranges of O. borealis. Arm bifurcation is reported in Cirrata for the first time, suggesting well-developed regeneration is present even in this ancient taxon of cephalopods. Ontogenetic increase of spermatophore length, i.e., when the spermatophores produced later during ontogenesis are larger than those produced earlier, is reported in Cirrata for the first time. The stomachs in all the studied specimens were at least one-third full, suggesting that O. borealis continues to feed and grow after reaching maturity. Polychaetes dominated over crustaceans in the stomach contents. Contrary to the assumption that Cirrata feed on relatively small prey only, large mature males of O. borealis consume polychaetes reaching 41.5–45.9% ML of the specimens.

就丰富度和多样性而言，深海头足类动物在深海生态系统中都很重要，但遭到了严重的研究。深海头足类动物中最引人入胜的群体之一是奇拉达（Cirrata），这是一种相对原始的章鱼。Opisthoteuthis是Cirrata中最大的属。的研究最少的物种Opisthoteuthis在大西洋，Opisthoteuthis北极光柯林斯，2005年来自九个样本只有我们的研究之前已知的，并没有关于它的生物被描述。描述了四只雄性，全部大于先前已知的最大大小（地幔长度为78-96毫米，比75毫米），并提供了物种的COI序列以简化对大西洋鸦片的鉴定。。我们的发现扩展了O的已知地理范围（北大西洋，从北向北60°到戴维斯和丹麦海峡以及冰岛-法罗岭），深度（878-1132 m）和温度（3.0-3.6°C）范围。北极虫。Cirrata首次报道了臂分叉，这表明即使在这个古老的头足类生物群中也存在发达的再生。首次在Cirrata中报道了精子体长度的自生增加，即，在本体形成过程中后期产生的精子比早先产生的精子大。所有研究标本中的胃都至少充满了三分之一，这表明北方稻达到成熟后继续喂养并成长。杂食动物在胃内容物中的甲壳类动物中占主导地位。相反，假设Cirrata饲料相对较小的猎物而已，大的成熟的男性O.北极光消耗多毛类达到标本的41.5-45.9％ML。