Prosymna is a specialized African snake genus lacking close relatives. The evolutionary relationships and history within Prosymna are poorly understood. Here we assembled a multi-gene data set including representatives for 11 of 16 species to investigate the phylogenetic relationships of this group. Our analyses support the monophyly of Prosymna and are congruent with species groups previously recognized on the basis of external morphology. Divergences among extant Prosymna began in the mid-Cenozoic, with the earliest divergence splitting northern from southern lineages. High-resolution computed tomography scans confirm that a specialized skull morphology is found across the genus and was probably present in the common ancestor of Prosymna. This specialization is exemplified by dentition featuring reduced anterior but greatly enlarged, blade-like posterior maxillary teeth and an unusually high degree of fusion of cranial bones. One species, P. visseri, has a hammer-like maxilla unlike that of any other known snake. Evidence for oophagy in Prosymna and the possible roles of morphological specializations in egg-slitting or egg-crushing feeding mechanisms are discussed.

中文翻译：

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饮食专家非洲铲鼻蛇的系统发育和独特头骨形态的进化（Lamprophiidae：Prosymna）

Prosymna是缺乏近亲的非洲专业蛇类。Prosymna内部的进化关系和历史知之甚少。在这里，我们收集了包括16个物种中11个物种的代表在内的多基因数据集，以调查该群体的系统发育关系。我们的分析支持Prosymna的单方面性，并且与先前基于外部形态学认识的物种组一致。现存的Prosymna之间的分歧始于新生代中期，最早的分歧是将北部和南部的血统分开。高分辨率计算机断层扫描扫描确认在整个属中发现了专门的颅骨形态，并且可能存在于颅骨的共同祖先中。Prosymna。这种专业化以牙列为例，其特征是前牙减少，但上颌后牙大而呈刀片状，后颅骨融合程度异常高。一个物种，P. visseri，具有锤状不同于任何其他已知的蛇颌骨。讨论了Prosymna中卵菌性的证据以及形态学专业化在卵分切或压碎卵的进食机制中的可能作用。