Three elasmobranch species of the genus Deania are currently reported in NE Atlantic waters: D. calcea, D. hystricosa and D. profundorum; however, in north Spanish waters (NE Atlantic), only D. calcea and D. profundorum have been caught. Among the criteria used to discriminate Deania species one is dermal denticle length and body colour. In this study the authors explore the feasibility of these criteria and examine other morphological characters to investigate if sexual or ontogenic features had relevance for the distinction of the species particularly those sampled in this study, D. calcea and D. profundorum. Molecular analyses were conducted to validate these results.

In D. calcea, dermal denticle length ranged from $340\mathrm{\mu }\mathrm{m}$ to $1400\mathrm{\mu }\mathrm{m}$ (763.$2\mathrm{\mu }\mathrm{m}$ $\pm$ 180.4 s.d.); in D. profundorum, dermal denticle length ranged from $195\mathrm{\mu }\mathrm{m}$ to $650\mathrm{\mu }\mathrm{m}$ (372.$3\mathrm{\mu }\mathrm{m}$ $\pm$ 111.7 s.d.). In both Deania species, a significant positive correlation was found between shark total length and dermal denticle length. Dermal denticles varied in size and shape along the shark body. These differences were significant both intra- and inter-specifically.

A multivariate analysis based on morphological characters was used to test differences between D. calcea and D. profundorum. The hierarchical analysis clearly identified three groups; two groups corresponded to each species, and a third group discriminated between small and large individuals of D. profundorum. The morphometric characters that contributed most to the divergence between both species were mainly related to the size of the dorsal fins, the inter-dorsal distance and the distances from the snout to the origin of each dorsal fin. Based on morphological characters, no sexual dimorphism was observed.

The phylogenetic tree was reconstructed with molecular COI sequences available on BOLD and those obtained in this study. The output tree discriminate D. calcea from D. profundorum, however could not separate molecularly D. calcea and D. hystricosa.

目前在东北大西洋水域报告了Deania属的三种弹性分支物种：D。calcea，D。hystricosa和D. profundorum ; 但是，在西班牙北部水域（东北大西洋），仅捕捞了D. calcea和D. profundorum。在用于区分迪亚尼亚物种的标准中，一种是真皮的齿长和体色。在这项研究中，作者探索了这些标准的可行性，并研究了其他形态特征，以研究有性或个体发育特征是否与该物种的区分有关，特别是在本研究中所采样的D. calcea和D. profundorum。进行了分子分析以验证这些结果。

在D. calcea中，真皮的齿状体长度范围为：$340\mathrm{\mu }\mathrm{米}$ 至 $1400\mathrm{\mu }\mathrm{米}$ （763。$2\mathrm{\mu }\mathrm{米}$ $\pm$180.4 sd）; 在D. profundorum中，真皮的齿长范围为：$195\mathrm{\mu }\mathrm{米}$ 至 $650\mathrm{\mu }\mathrm{米}$ （372。$3\mathrm{\mu }\mathrm{米}$ $\pm$111.7 SD）。在两种Deania物种中，鲨鱼的总长度和真皮牙质的长度之间存在显着的正相关。沿鲨鱼体的皮肤细齿的大小和形状各不相同。这些差异在种内和种间均很显着。

基于形态学特征的多元分析用于检验跟骨D. calcea和D. profundorum之间的差异。层次分析清楚地确定了三组：两组分别对应于每个物种，第三组区分深层D. profundorum的个体。导致这两个物种之间差异最大的形态特征主要与背鳍的大小，背鳍间距离以及从鼻子到每个背鳍起点的距离有关。根据形态特征，未观察到性二态性。

用BOLD上可获得的分子COI序列和本研究获得的分子COI序列重建了系统树。输出树可将D. calcea与D. profundorum区别开来，但无法从分子上分离D. calcea和D. hystricosa。