A new crustacean from the Herefordshire (Silurian) Lagerstätte, UK, and its significance in malacostracan evolution.
A new crustacean from the Herefordshire (Silurian) Lagerstätte, UK, and its significance in malacostracan evolution.
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DOI：
10.1098/rspb.2017.0279
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发表时间：
2017-03-29
期刊：
影响因子：
--
通讯作者：
Legg D
中科院分区：
文献类型：
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作者：
Siveter DJ;Briggs DE;Siveter DJ;Sutton MD;Legg D
Cascolus ravitis gen. et sp. nov.是一种三维保存的甲壳类化石，具有柔软的部分，来自英国赫里福德郡（志留纪）Lagerstätte。它的特征是头部有一个头盾和五对肢体，胸部（pereon）有九个附属物承载节，随后是一个无足腹部（pleon）。除了第一个外，所有的附属物都是双枝的，有一个颚基。下颌后附肢彼此相似，并带有花瓣状的上足，可能是生殖循环系统的一部分。分支系统分析解决了新的分类单元作为一个茎组leptostracan（软甲纲）。这种保存完好的节肢动物提供了新的见解的附属器形态，tagmosis和可能的基础软介类的消化循环生理的演变。
Cascolus ravitis gen. et sp. nov. is a three-dimensionally preserved fossil crustacean with soft parts from the Herefordshire (Silurian) Lagerstätte, UK. It is characterized by a head with a head shield and five limb pairs, and a thorax (pereon) with nine appendage-bearing segments followed by an apodous abdomen (pleon). All the appendages except the first are biramous and have a gnathobase. The post-mandibular appendages are similar one to another, and bear petal-shaped epipods that probably functioned as a part of the respiratory–circulatory system. Cladistic analysis resolves the new taxon as a stem-group leptostracan (Malacostraca). This well-preserved arthropod provides novel insights into the evolution of appendage morphology, tagmosis and the possible respiratory–circulatory physiology of a basal malacostracan.