Munari Cristina, Wolf Marion A, Infantini Vanessa, Moro Isabella, Sfriso Adriano, Mistri Michele
Department of Chemical and Pharmaceutical Sciences, University of Ferrara, Via Fossato di Mortara 17, 44121 Ferrara, Italy.
Zootaxa. 2020 Feb 19;4742(1):zootaxa.4742.1.10. doi: 10.11646/zootaxa.4742.1.10.
The present study describes a new species of spionid polychaete, Streblospio eridani n. sp., from the Italian coasts of the Northern Adriatic Sea (Mediterranean Sea). This new spionid species was recorded from shallow lagoon and marine habitats: the soft bottoms of the Sacca di Goro (Po River Delta), on October 2017, and the Lido di Dante (Emilia Romagna), between 2016 and 2017. The re-assessment of spionid specimens from other lagoon systems (the Valli di Comacchio and the Valle di Gorino) led us to recognize the presence of this species in the northern Adriatic Sea since 2009. Streblospio eridani n. sp. had low occurrence and density at the marine site Lido di Dante and at the lagoon sites Valli di Comacchio and Valle di Gorino; whereas it reached the highest density of 21,213.3 ind. m-2 at the Sacca di Goro. Morphologically this new species is characterized by dorsal (occipital) papilla on the first chaetiger, sabre chaetae and hooded hooks first appearing on chaetigers 7, hooks with 4-5 pairs of small secondary teeth, pygidium with ventral lappets, and brooding branchiate structures between chaetigers 13 and 28. In the phylogenetic reconstruction, based on the mitochondrial cytochrome c oxidase subunit I (COI) gene, the Adriatic taxon results clearly indicate that this is distinct from the other species of the genus and formed a well-supported clade with other Streblospio sp. specimens from India. Nucleotide divergences calculated between the Adriatic specimens and the other Streblospio species are higher than the intraspecific range reported for the genus and support the description of a new species. Morphological characters important for differentiation of the new species herein described from congeneric species are discussed and an updated key for Streblospio species is provided.
本研究描述了一种来自亚得里亚海北部意大利海岸（地中海）的新种多毛纲矶沙蚕科动物，即埃里达诺斯矶沙蚕（Streblospio eridani n. sp.）。该新种矶沙蚕记录于浅泻湖和海洋栖息地：2017年10月在戈罗潟湖（波河三角洲）的软底，以及2016年至2017年期间在但丁利多（艾米利亚-罗马涅）。对来自其他泻湖系统（科马基奥谷和戈里诺谷）的矶沙蚕标本重新评估后，我们确认自2009年以来该物种就存在于亚得里亚海北部。埃里达诺斯矶沙蚕在海洋站点但丁利多以及泻湖站点科马基奥谷和戈里诺谷的出现频率和密度较低；而在戈罗潟湖其密度最高达到21213.3个个体/平方米。形态上，该新物种的特征为：第一刚节具背（枕）乳突，军刀状刚毛和带帽钩首先出现在第7刚节，钩具4 - 5对小的次生齿，尾节具腹叶，以及第13至28刚节之间有育幼鳃状结构。在基于线粒体细胞色素c氧化酶亚基I（COI）基因的系统发育重建中，亚得里亚分类群的结果清楚地表明，该物种与该属的其他物种不同，并且与来自印度的其他矶沙蚕属标本形成了一个得到充分支持的分支。计算得出的亚得里亚标本与其他矶沙蚕物种之间的核苷酸差异高于该属报道的种内范围，支持了新物种的描述。讨论了对于区分本文所述新物种与同属物种重要的形态特征，并提供了矶沙蚕属物种的更新检索表。
