Keiler Jonas, Richter Stefan, Wirkner Christian S
Allgemeine & Spezielle Zoologie, Institut für Biowissenschaften, Universität Rostock, Universitätsplatz 2, Rostock 18055, Germany.
J Morphol. 2013 Jul;274(7):759-78. doi: 10.1002/jmor.20133. Epub 2013 Mar 19.
The morphological transformation of hermit crabs into crab-like king crabs in the evolution of decapod crustaceans represents a remarkable case of carcinization or evolutionary shaping into a crab-like form. In this study, we focus on internal organs such as the hemolymph vascular system and adjacent anatomical structures of several Recent hermit crab (Paguridae) and king crab (Lithodidae) species. There are various correspondences in the morphology of the arterial systems in the dorsal cephalothorax of the two taxa, especially with regard to the anterior aorta, anterior lateral arteries, and hepatic arteries. In the pleon, the posterior aorta in both taxa displays a proximal bifurcation and follows an asymmetrical course. The ventral vessel system, on the other hand, which mainly supplies the limbs, differs significantly between the taxa, with pagurids displaying the plesiomorphic condition. The pattern of the ventral vessel system in Lithodidae is influenced by morphological transformations of integumental structures during carcinization. One of these transformations was the broadening of the sternites, which resulted in a widening of the space between the endosternites. In addition, changes in the morphology of the endophragmal skeleton in Lithodidae led to an increase in the potential for intraspecific variability and interspecific variation in the arterial branching pattern.
在十足目甲壳动物的进化过程中，寄居蟹向蟹状帝王蟹的形态转变代表了一个显著的“蟹化”案例，即进化成蟹状形态。在本研究中，我们聚焦于几种现代寄居蟹（寄居蟹科）和帝王蟹（石蟹科）物种的血淋巴血管系统等内部器官以及相邻的解剖结构。这两个类群头胸部背面动脉系统的形态存在各种对应关系，特别是在前主动脉、前侧动脉和肝动脉方面。在腹部，两个类群的后主动脉都显示出近端分叉并呈不对称走向。另一方面，主要为肢体供血的腹血管系统在这两个类群之间有显著差异，寄居蟹呈现出原始状态。石蟹科腹血管系统的模式受到蟹化过程中体表结构形态转变的影响。其中一个转变是胸腹板变宽，这导致内胸板之间的空间变宽。此外，石蟹科内骨骼形态的变化导致动脉分支模式的种内变异性和种间变异性增加。
