BACKGROUND As the role of Ambystoma mexicanum, or the Mexican axolotl, expands in research applications beyond its traditional use in studies of limb regeneration, a staging table that is more anatomically extensive is required. Here, we describe axolotl skull development as it relates to previously established developmental stages that were based on limb development. RESULTS We find that most key developmental events in the skull correspond to these previously established stages, creating easily recognizable stages of axolotl throughout skull morphogenesis. CONCLUSIONS With this complementary staging table in hand, researchers can stage axolotl larvae when limb data are missing or incomplete, or when cranial data alone is available.

中文翻译：

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Ambystoma mexicanum 的正常发育：基于茜素红 S 染色的颅骨补充分期表。

背景随着墨西哥蝾螈或墨西哥蝾螈的作用在研究应用中的扩展超出其在肢体再生研究中的传统用途，因此需要在解剖学上更广泛的分期表。在这里，我们描述了蝾螈头骨的发育，因为它与以前建立的基于肢体发育的发育阶段有关。结果 我们发现头骨中的大多数关键发育事件对应于这些先前确定的阶段，在整个头骨形态发生过程中创造了易于识别的蝾螈阶段。结论 有了这个互补的分期表，研究人员可以在肢体数据缺失或不完整，或者只有颅骨数据可用时对蝾螈幼虫进行分期。