Early development of the Gulf Coast toad, Bufo valliceps Wiegmann. American Museum novitates ; no. 1842

Abstract

"The development of Bufo valliceps from the fertilized egg through metamorphosis is described. Forty-six stages of development are defined and illustrated. The diagrams are intended as a reference series for comparative studies of embryos and tadpoles of the genus Bufo in North America. Tadpoles at the same stage of development vary in absolute body dimensions. Moreover, the body dimensions undergo continuous change throughout development. Measurements of tadpoles expressed as absolute values are of limited use as taxonomic criteria. Relative body ratios are constant during the greater part of larval development. The usefulness of relative body proportions as taxonomic criteria awaits the study of ontogenetic changes in tadpoles of other species of toads. The pigment pattern of the tail and the nature of the mouth parts serve best to characterize the tadpoles of B. valliceps. Comparisons with tadpoles of other toad species should be made only with equivalent growth stages"--P. 29.