The toe tip friction surface in six species of Ambystoma (A. annulatum, A.maculatum, A.opacum, A. talpoideum, A. texanum, and A. tigrinum) from Arkansas was examined using scanning electron microscopy. We found no sexual dimorphism in cell surface ultrastructure. Variation within and between species was considerable. The most active burrower, A. tigrinum, possessed the most disorganized cell surface, whereas the least active burrowers (A.annulatum, A.maculatum, and A. opacum) had morphologically similar and relatively smooth toe tips. In A. talpoideum and A. texanum, cell surfaces exhibited microprojections. Only these two species possessed mucous pores in close proximity to the friction surface. The microstructure of cell surfaces transcended species groups in Ambystoma and would not represent a reliable taxonomic tool.

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