中国林蛙与中华蟾蜍蝌蚪颅骨形态的系统进化比较

Phylogenetic Comparison of Rana chensinensis and Bufo gargarizans Based on the Morphology of Larval Chondrocranium

对无尾两栖动物系统进化的研究,主要是基于经典的形态学、现代分子生物学等技术。无尾两栖动物蝌蚪的进化与成体的进化可能是两个独立的过程,所以无尾两栖类蝌蚪形态及发育特征也可以作为研究系统进化的重要指征。本文对中国林蛙(Rana chensinensis)及中华蟾蜍(Bufo gargarizans)变态前蝌蚪的软骨性颅骨及鳃部骨骼进行形态学描述,基于幼体形态特征,进行系统建树。建树结果支持Orton将无尾两栖类蝌蚪划分为4种类型,认为最原始的类群为Ⅲ型蝌蚪,与Tihen的观点一致。新蛙亚目的中国林蛙和中华蟾蜍蝌蚪属Ⅳ型,是最进化的类群。

The phylogenetic relationships among anuran amphibians are revealed mainly by classical morphology and modern molecular biology. The characters of larval morphology and development are also important indicators for the phylogenetic relationships,because frogs and tadpoles have evolved independently. Herein, the morphology of larval chondrocranium and hyobranchial apparatus are described in the Chinese forest frog Rana chensinensis and the big toad Bufo gargarizans,and the phylogenetic tree is constructed from the larval characters. The results of our work support Orton＇s opinion that anuran larvae can be divided into four types, and are identical with Tihen＇s view that anurans with Type-Ⅲ larvae were the most basal. The Type-Ⅳ larvae of R. chensinensis and B. gargarizans,which belong to the Neobatrachia,are the most advanced.