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The banded water snake (Nerodia fasciata fasciata) and the Eastern cottonmouth (Agkistrodon piscivorus piscivorus) were the focal species in a long-term mark and recapture study in the upper coastal plain of South Carolina, USA. Recapture rates were low for both species. Female N. fasciata were significantly larger than males. Male A. piscivorus were larger than females but not significantly. Age structure and sex ratios were determined for these populations. Recapture latency was greater for A. piscivorus than for N. fasciata. There was little dietary niche overlap between these two species. Nerodia fasciata ingested significantly more fish headfirst and more amphibians tail first. Growth rates were also calculated for both species. Litter size, offspring size, relative clutch mass and parturition dates were determined for N. fasciata.

Loss of wetlands throughout the southeastern United States threatens the persistence of the region's highly diverse freshwater fauna. Losses are especially concerning for rare species that maintain small or fragmented ranges, zoogeographies that characterize many of the region's numerous freshwater endemics. We assayed nuclear and mitochondrial DNA sequence data from the Pine Barrens Treefrog (Hyla andersonii), a rare species distributed across the Atlantic and Gulf coastal plains. We hypothesized that the species' evolutionary history has been associated with changes in wetlands during Quaternary interglacials and that the contemporaneous extent of wetlands is positively correlated with population genetic diversity. Genetic variation was highest in North Carolina and South Carolina and lowest in New Jersey and Florida. Mean times to common ancestry ranged from 132,486 to 1,290,605 yr before present, and effective sizes ranged from 4,241 individuals in New Jersey to 403,718 individuals in North Carolina. Population migration rates were generally very low (

We used radiotelemetry to study the movements and habitat use in a population of Nerodia fasciata fasciata in the upper coastal plain of South Carolina from 2002 to 2006. Snakes that were surgically implanted with radiotransmitters were tracked during late spring of each year and located most days until the onset of hibernation in mid-November. Data were divided into summer and fall for seasonal analysis. Most home-range estimates and associated measures were significantly smaller during fall. Banded watersnakes used shoreline and littoral zone habitats in excess of their availability and used open water and terrestrial habitats relatively infrequently. Shoreline habitats were used more often during the fall, whereas littoral zone habitats were used more in the summer. Movement frequency was high relative to what has been reported for other Nerodia species. Females used shoreline habitats more than males, whereas males used littoral zone habitats more frequently.

Terrestrial habitats around wetlands are important in wetland conservation because many vertebrate animals use them during part of their life cycle. There is relatively little information concerning terrestrial habitat use by aquatic snakes adjacent to wetlands. Radiotelemetry was used to study the spatial ecology and terrestrial habitat use of Nerodia e. erythrogaster in the upper coastal plain of northern South Carolina. Snakes used terrestrial habitats extensively during the summer and fall. Use of both wetlands and southern mixed hardwood forest were significantly greater than predicted by habitat availability within the snakes' home ranges. Agricultural fields were used significantly less than predicted. A distance of 344 m from wetlands is necessary to encompass 95% of the terrestrial localities documented in this study. Home range estimates based on 95% fixed kernels were significantly larger than those calculated using the 95% minimum convex polygon methods. Home range estimates for this ...

The discovery of three new species of Synophis snakes from the eastern slopes of the tropical Andes in Ecuador and Peru is reported. All previous records of Synophis bicolor from eastern Ecuador correspond to Synophis bogerti sp. n., which occurs between 1000-1750 m along a large part of the Amazonian slopes of the Ecuadorian Andes. In contrast, Synophis zamora sp. n. is restricted to southeastern Ecuador, including Cordillera del Cóndor, between 1543-1843 m. Synophis insulomontanus sp. n. is from the eastern slopes of the Andes in central and northern Peru, between 1122-1798 m, and represents the first record of Synophis from this country. All three new species share in common a large lateral spine at the base of the hemipenial body. A molecular phylogenetic tree based on three mitochondrial genes is presented, including samples of Diaphorolepis wagneri. Our tree strongly supports Synophis and Diaphorolepis as sister taxa, as well as monophyly of the three new species described here and Synophis calamitus. Inclusion of Synophis and Diaphorolepis within Dipsadinae as sister to a clade containing Imantodes, Dipsas, Ninia, Hypsiglena and Pseudoleptodeira is also supported.ResumenSe reporta el descubrimiento de tres especies nuevas de serpientes

The chromosomal location of rDNA repeats has become an important tool in systematics (Bickham and Rogers, 1985; King et al., 1986; Odierna et al., 1987; Porter et al., 1991, 1994; Amemiya et al., 1993). Ribosomal DNA is found in the nucleolus organizer regions (NORs) (Ritossa and Spiegelman, 1965) and is visualized through in situ hybridization (Porter et al., 1991), N-banding (Gerlach, 1977), or Ag-staining (Goodpasture and Bloom, 1975; Howell and Black, 1980). Chromosomal evolution in snakes has not been

form which was described as Ambystoma barbouri (Kraus and Petranka, 1989) and is found in central Kentucky, southeastern Indiana, and southwestern Ohio; the pond form which is found throughout the rest of the range of A. texanum (Petranka, 1982b). The stream-form deposits eggs on the undersides of rocks in streams and produces larger, but fewer, eggs per female than the pond form. Pond-breeding A. texanum attach their eggs to twigs or aquatic vegetation in vernal ponds and are explosive breeders, whereas the stream form is a nonexplosive breeder (Petranka, 1982b, 1984a, 1984b). Explosive breeders mate in large numbers during or immediately following periods of rainfall, whereas nonexplosive breeders mate in smaller numbers throughout the breeding season and seem less dependent on rainfall (Petranka, 1984a). The reproductive biology of pond-breeding A. texanum has received considerable attention in the central