Variation in chelonian reproductive patterns is well documented. Previous studies of loggerhead musk turtles (Sternotherus minor) reproduction have not attempted to control for variation in latitude, local population differences, and seasonal variation. The present study attempts to control for these variables by collecting turtles from one population for one reproductive season. The reproductive pattern of S. minor at the southern limit of its range (Central Florida) is compared to those of S. minor studied elsewhere. Both male and female musk turtles mature after five to six years and at approximately 60mm plastron length. No sexual dimorphism in overall body size is evident. There is a significant relationship between testis mass and male body size. Spermatogenesis begins in June as testes begin to enlarge. A peak in the testicular cycle is observed in August and September followed by testicular regression from October through January. A germinal quiescent phase is evident from February through April. Vitellogenesis in females begins in mid-September and the first clutch is laid in late October. Ovipositions continue until mid-June when follicular regression begins. A brief but distinct ovarian quiescent period occurs in August. Mean clutch size is 3.0 (range= 1-5). Clutch size and clutch mass were significantly correlated with body size. Egg length is not significantly correlated with clutch size or plastron length. Four clutches per year are common and some females probably produce five. Reproductive potential and individual reproductive effort are both correlated with body size. Testicular activity peaks six months after a peak in the ovarian cycle. Similarities with other studies of Sternotherus minor include: timing of the reproductive cycles, mean female size, and size and age at maturity. Mean clutch size in Central Florida is significantly larger than elsewhere. This difference is explained by the fact that more females produce three and four eggs. While similarities and differences in reproductive characteristics do exist between Central Florida S. minor and more northern populations, it is clear that those similarities and differences must be interpreted with respect to the methods of data collection used. Annual reproductive potential is enhanced in the Central Florida population. This is explained by greater resource availability which is translated into a greater reproductive output.

The squamata reptiles present a wide array of reproductive strategies. In the genus Lepidophyma from the neotropical family Xantusiidae, there are 19 species, all of them live- bearing and diploid. Obligatory unisexuality is also present in some species. This obligatory unisexuality did not evolve via hybridization, which is unique among vertebrates. The genus thus presents a very interesting, but still poorly little explored group. Only recently our team has discovered a facultative unisexuality in Lepidophyma smithii. The unisexually produced offsprings are not fully homozygous are of both sexes, which is unique for vertebrates as well. The aim of my work is to describe the basic reproductive biology of this species, e.g. the relationship between female size and clutch size and offspring size. Additionally, my work focuses on sexual dimorphism. I tested whether L. smithii is dimorphic in body length and head size. These traits are often sexually dimorphic in squamatesu. Also, I documented the ontogeny of sexual dimorphism and reconstructed growth curves for males and females.