Trueb L, Hanken J
Museum of Natural History, University of Kansas, Lawrence 66045-2454.
J Morphol. 1992 Oct;214(1):1-41. doi: 10.1002/jmor.1052140102.
Postembryonic skeletal development of the pipid frog Xenopus laevis is described from cleared-and-stained whole-mount specimens and sectioned material representing Nieuwkoop and Faber developmental Stages 46-65, plus postmetamorphic individuals up to 6 months old. An assessment of variation of skeletogenesis within a single population of larvae and comparison with earlier studies revealed that the timing, but not the sequence, of skeletal development in X. laevis is more variable than previously reported and poorly correlated with the development of external morphology. Examination of chondrocranial development indicates that the rostral cartilages of X. laevis are homologous with the suprarostral cartilages of non-pipoid anurans, and suggests that the peculiar chondrocranium of this taxon is derived from a more generalized pattern typical of non-pipoid frogs. Derived features of skeletal development not previously reported for X. laevis include 1) bipartite formation of the palatoquadrate; 2) precocious formation of the adult mandible; 3) origin of the angulosplenial from two centers of ossification; 4) complete erosion of the orbital cartilage during the later stages of metamorphosis; 5) development of the sphenethmoid as a membrane, rather than an endochondral bone; and 6) a pattern of timing of ossification that more closely coincides with that of the pelobatid frog Spea than that recorded for neobatrachian species.
从经过透明和染色的整体标本以及代表Nieuwkoop和Faber发育阶段46 - 65的切片材料，以及6个月大以内的变态后个体，描述了非洲爪蟾（Xenopus laevis）胚胎后骨骼发育情况。对单个幼虫群体内骨骼发生变异的评估以及与早期研究的比较表明，非洲爪蟾骨骼发育的时间比之前报道的更具变异性，与外部形态发育的相关性较差，但骨骼发育顺序不变。对软骨颅发育的检查表明，非洲爪蟾的吻部软骨与非非洲爪蟾无尾类的吻上软骨同源，并表明该分类群独特的软骨颅源自非非洲爪蟾蛙类典型的更普遍模式。非洲爪蟾以前未报道过的骨骼发育衍生特征包括：1）方骨的二分形成；2）成年下颌骨的早熟形成；3）角脾骨由两个骨化中心起源；4）变态后期眶软骨完全侵蚀；5）蝶筛骨作为膜性骨而非软骨内骨发育；6）骨化时间模式与盘舌蟾科蛙类Spea的更接近，而与新蛙类物种记录的不同。
