Variation in the foot muscles of frogs of the family Myobatrachidae

The hind-foot musculature of representatives of all myobatrachid frog gener a was examined with a view to finding phylogenetic characters and character s correlated with the burrowing habit. Despite much intraspecific variation , evidence was found to support the monophyly of Mixophyes (possession of a fibrous section in the tendon of insertion of the m. lumbricalis longus di giti V, tendinous insertion of the m abductors brevis dorsalis digiti V), R heobatrachus (threefold insertion of the m. extensor longus digiti IV), Neo batrachus + Heleioporus (possession of the m. lumbricalis longus digiti II) , Pseudophryne + Metacrinia (loss or reduction of medial slip of the m. lum bricalis brevis digiti V), Adelotus + Heleioporus + Limnodynastes (minus L. ornatus-group) + Neobatrachus + Notaden (possession of a transversus-like muscle between the first metatarsus and the prehallux), and Rheobatrachus Myobatrachinae (reduction of the m. plantaris brevis plantaris digiti V). Differences were found in the musculature associated with the metatarsal tu bercles between (a) rear-foot-burrowing frogs of the genera Notaden, Neobat rachus, Heleioporus and Limnodynastes (minus L. ornatus and L. spenceri); ( b) L. ornatus and L. spenceri; and (c) Uperoleia. The differences indicate separate evolution of burrowing in these taxa. A new muscle, the m. adducto r praehallucis, is described. From its structure and distribution among spe cies, this muscle appears to be associated with the burrowing habit.