We investigated population structure and life history traits in syntopic populations of Desmognathus aeneus and Desmognathus wrighti in the southern Nantahala Mountains, NC. The two species occupy similar microhabitats in the spring months, occurring in clumps of moss and damp leaf litter and under stones and logs in deciduous forests bordering streams and seepages. We examined the reproductive organs in living individuals taken in large samples in early spring. The goal was to determine sex and reproductive status. We confirmed these assessments by dissections of small numbers of preserved individuals collected in the same months of later years. The sample of D. wrighti included first-year juveniles (8 mo), second-year juveniles and adult males (20 mo), and third-year and older adults (≥ 32 mo). Similarly, the sample of D. aeneus contained first-year (11 mo), second-year (23 mo), and third-year and older (≥ 35 mo) individuals, in the same reproductive categories as identified in D. wrighti. The age differences reflect different oviposition times, estimated as 1 May in D. aeneus and 1 August in D. wrighti. In both species, we estimated that males attain sexual maturity in their second or third year, and that females usually oviposit initially at age 3 years. There is considerable overlap in body size between species. Within species, adult females average larger than males, in part a consequence of earlier maturation of males, but maximum sizes of males and females are similar.