The leaf or monkey frogs of the hylid subfamily Phyllomedusinae are a unique group of charismatic anurans. We present a molecular phylogenetic analysis that includes 45 of the 60 species of phyllomedusines using up to 12 genes and intervening tRNAs. The aims were to gain a better understanding of the phylogenetic position of Phrynomedusa, test the monophyly and explore the relationships among several putative lineages (Hylomantis, the H. buckleyi Group, Phasmahyla, the four species groups of Phyllomedusa, and the species of Phyllomedusa that remain unassigned to any group), and to examine the implications of our phylogeny for the evolution of several characters in phyllomedusines. The analyses resulted in a well-supported phylogenetic hypothesis that provides a historical framework for a discussion of the evolution of characters associated with reproductive biology, gliding behaviour, the physiology of waterproofing, and bioactive peptides. Implications include an earlier origin for eggless capsules than for leaf-folding behaviour during amplexus, two independent origins of gliding, and an earlier origin of reduction in evaporative water loss than uricotelism, which is a result that originally was predicted on the basis of physiology alone. Furthermore, our results support the prediction that bioactive peptides from different peptide families are to be expected in all species of Phyllomedusinae. Hylomantis (as recently redefined) is shown to be paraphyletic and the synonymy of Agalychnis is revised to remedy this problem by including both Hylomantis and Pachymedusa.

Despite considerable attention that other groups of reptiles have received, few descriptions of the development and sequences of chondrification and ossification of the entire skeleton of turtles exist. Herein, the adult skeleton of the spiny softshell turtle, Apalone spinifera (Testudines: Trionychidae), is described; this description forms a basis of comparison for the embryonic skeleton and its ontogenesis. Descriptions are made on the basis of cleared and double-stained embryos and dry skeletal postembryonic specimens. The embryonic chondrocranium of A. spinifera is described and compared to those of Emys orbicularis and Caretta caretta, the sequence of chondrification of fore- and hindlimbs are compared with published descriptions of Chelydra serpentina and Chrysemys picta, and the sequence of ossification of elements is compared with those of C. serpentina, Lacerta vivipara, and Alligator mississippiensis. In A. spinifera, the first elements that ossify (Stage 17) are associated with the dermatocranium and mandible, followed by elements of the dermal skull table, lower jaw, and dermal elements of the plastron. In A. spinifera, the sequence of chondrification of limb elements is similar to that of C. serpentina; however, the sequence of ossification varies greatly among Apalone, Chelydra, Lacerta, and Alligator.

Patterns of formation and sequence of ossification of the entire skeleton are described for the snapping turtle Chelydra serpentina, based on new and previously published data. Differences in the sequences of ossification events are described and demonstrate considerable intraspecific variation in these developmental data. The chondrocranium of a late developmental-stage specimen is described and illustrated as baseline data for comparative studies. Patterns of formation and chondrification of forelimb and hind limb elements are generally consistent with those of previous studies; however, conspicuous differences in the patterns of ossification are observed among metapodial and phalangeal elements. In the cranium, patterns of ossification of dermal elements are generally more variable than are those of endochondral elements of the braincase, and as in previous studies, endochondral elements ossify after dermal elements. Documented intraspecific variation in sequence and timing of formation, chondrification, and ossification of skeletal elements should serve as a caveat for those conducting studies of phylogeny, heterochrony, and evolution with these data. Causes of natural and induced variation are discussed briefly.