The Arctic Ocean is a unique ecosystem hosting a biodiversity that has not yet been elucidated in full detail. There is increasing evidence that there are more kelp species constricted to Arctic/sub‐Arctic habitats hitherto not well investigated, such as Hedophyllum nigripes, which is morphologically very similar to cold‐temperate Laminaria digitata. Hedophyllum nigripes was originally described as L. nigripes by Agardh from Spitsbergen but has often been misidentified as L. digitata in the European Arctic. We initiated a systematic algal survey along a depth gradient (0–7.5 m) in Kongsfjorden (Spitsbergen) in June and July 2015 and thereby confirmed a predominant presence of H. nigripes (73%). Hedophyllum nigripes is occurring between 0 and 7.5 m while L. digitata was most abundant at 2.5 m depth. Hedophyllum nigripes individuals were generally younger (2.3 vs. 3.6 years) and stipe and blade length shorter (31 vs. 54 cm and 76 vs. 96 cm, respectively) compared to L. digitata. A combination of molecular (COI‐5P) and morpho‐anatomical tools (presence of sori and mucilage ducts in the stipe) was used to differentiate specimens of H. nigripes and L. digitata. Both kelp species were indistinguishable in most cases by external blade and stipe morphology. The different blade shapes represented different ontogenetic stages rather than phenotypic plasticity. The presence of mucilage ducts in the stipe was correlated with H. nigripes and changed with depth from 17%, 36%, and 85% at 2.5, 5, and 7.5 m, respectively. In addition, all summer fertile specimens were L. digitata.

中文翻译：

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菌柄中的 DNA 条形码和粘液管揭示了 Kongsfjorden（斯匹次卑尔根岛）存在 Hedophyllum nigripes（海带目、褐藻纲）。


北冰洋是一个独特的生态系统，其生物多样性尚未得到详细阐明。越来越多的证据表明，有更多的海带物种局限于北极/亚北极栖息地，迄今为止尚未得到充分研究，例如Hedophyllum nigripes，其形态与冷温带海带非常相似。 Hedophyllum nigripes最初被来自斯匹次卑尔根岛的 Agardh 描述为L. nigripes ，但在欧洲北极经常被误认为是L. digitalata 。我们于 2015 年 6 月和 7 月在 Kongsfjorden（斯匹次卑尔根岛）沿深度梯度（0-7.5 m）启动了系统性藻类调查，从而证实了H. nigripes的主要存在（73%） 。 Hedophyllum nigripes出现在 0 至 7.5 m 深度之间，而L. digitalata在 2.5 m 深度最为丰富。与趾状黑叶草相比，黑叶黑叶草个体通常更年轻（2.3 岁对 3.6 岁），柄和叶片长度更短（分别为 31 厘米对 54 厘米和 76 厘米对 96 厘米）。结合分子（COI-5P）和形态解剖工具（菌柄中存在囊肿和粘液管）来区分H. nigripes和L. digitalata标本。在大多数情况下，通过外部叶片和叶柄形态无法区分这两种海带。不同的叶片形状代表不同的个体发育阶段，而不是表型可塑性。菌柄中粘液管的存在与H. nigripes相关，并随深度变化，在 2.5、5 和 7.5 m 处分别为 17%、36% 和 85%。此外，所有夏季可育的标本都是L.digitata 。