The Herpetological Journal

pp.1-7

Authors: Klaus Weddeling, Monika Hachtel, Ulrich Sander And David Tarkhnishvili

Abstract: Drift fences are frequently used to sample amphibians for population studies. Thus, some researchers do not mark animals, but use capture rates at the drift fence as an indicator of population size. Other workers use mark-recapture techniques to estimate population sizes. These approaches require different amounts of effort and lead to different results. Our study compares several estimates of population size for alpine newts (Triturus alpestris) and smooth newts (Triturus vulgaris) in five breeding ponds surrounded by pennanent drift fences and pitfall traps. The estimates based on mark-recapture techniques (Petersen method) do not vary substantially between the two modes of recapture applied (funnel traps, and drift fences with pitfall traps). These estimates give even better results than simple counts if a substantial part of the newt populations remain within the drift fences throughout the year. While unrecognized trespass by newts appears to be a rare event, some newts may leave a pond for a short time even during the breeding season. This is an important source of bias for population estimates in studies based on counts at drift fences when animals are not marked.

Keywords: capture methods, mark-recapture, Triturus alpestris, Triturus vulgaris

pp.9-12

Authors: Xin Lu

Abstract: Body reserves of temperate anurans go through an annual cycle in response to highly seasonal environments. Here l describe how changes in relative mass of storage organs of Rana chensinensis occurring in northern China contributed to this cycle. Body reserves of both sexes dropped to their lowest levels after hibernation, and experienced a resting period of five months, then the reserves started increasing and attained peaks shortly before hibernating. During hibernation, the frogs' ovaries kept growing and liver and fat bodies declined accordingly. Based on comparable data in other studies, two distinct models of ovarian development in temperate anurans, hibernation-growth and non-hibernation-growth, are suggested. I also show a decreased relative ovarian mass with increased climate harshness.

Keywords: body reserves, ecological energetics, environmental physiology, Ranidae

pp.13-19

Authors: José C. Brito

Abstract: The diet of Vipera latastei was investigated in northern Portugal from 1998 to 2002. Palpation of stomach contents and forced defaecation from 1 90 snake specimens resulted in the recovery of 83 identifiable prey items. V. latastei preys on four species of small mammal (76%), two lizard species ( 14%), three amphibian species (5%) and arthropods s.l. (5%). Estimates of prey availability demonstrated that the most common prey were also the most frequent prey consumed. No differences between the sexes were detected in terms of the proportion of snakes with prey or diet composition. However, there was an ontogenetic shift in diet composition. Juveniles fed mostly on ecthotermic prey (60%), the majority of subadults fed on insectivorous mammals and lizards (60%), and adults fed mainly on rodents ( 8 8%). This ontogenetic shift is mostly due to the morphological constraints imposed on the juvenil es, which cannot swallow large prey items. There is a positive correlation between snake size and prey size. V. latastei is selective in terms of both the species and size of prey ingested, with larger snakes being more selective than smaller snakes. Larger snakes have a narrower food niche breadth than smaller snakes, but their diet composition overlaps moderately. There is seasonal variation in the diet composition, with snakes taking amphibians mainly in spring and autumn, lizards in spring, and mammals in summer and autumn. Feeding frequencies indicate that both males and females - and subadults and adults - consume prey more frequently during summer.

Keywords: dietary habits, food selection, prey availability, snakes, Viperidae

pp.21-33

Authors: Anita Malhotra And Roger S. Thorpe

Abstract: Trimeresurus venustus Vogel, 1991 was described from southern Thailand in I 991 and distinguished from the similar T. kanburiensis primarily by the following characters : 21 ' scale rows at midbody rather than I 9 and less irregular and i ndented supraoculars. H owever, very few specimens of T. kanburiensis were known at the time of this description, and the name T. venustus has not been universally accepted. Recently, live specimens from the type locality of T. kanburiensis in western Thailand have become available, allowing a reassessment of the status - of the southern Thai population. Phylogenetic analysis of two mitochondrial gene regions indicated that specimens from south Thailand are genetically quite distinct from the specimen from the type locality, and the former are more closely related to T. macrops than to T. kanburiensis. We present a multivariate morphometric analysis of the six specimens of T. kanburiensis from the type locality that are now known and twenty specimens from southern Thailand . Despite the small sample size, it is clear that some of the diagnostic characteristics used to define T. venustus are invalid. We conclude that the current evidence indicates that T. venustus is a valid species, and present new diagnostic characters to separate it from T. kanburiensis.

Keywords: Crotalinae, systematics, Thailand, Trimeresurus kanburiensis, Yiperidae

pp.35-45

Authors: Georgia Mantziou, Nikos Poulakakis, Petros Lymber Akis, Efstratlos Valakos And Moysis Mylonas

Abstract: The genus Mauremys (Chelonia, Bataguridae) is widely distributed throughout Asia, Europe and NW Africa. Three species ( Mauremys caspica, Mauremys rivulata and Mauremys leprosa) are discontinuously distributed around the Mediterranean region. Present distributions are much smaller than those documented with in the fossil record of Mauremys in the Mediterranean region. All three extant species are identified on the basis of morphology. In the present study we compare partial mitochondrial DNA sequences of cyt-b from J 6 populations of Mauremys rivulata from Greece, one from Jordan (M. rivulata), two from Syria (M. caspica) and one from Morocco (M. leprosa). Comparison of cyt-b partial sequences supports the monophyly of the three species considered, as well as their proposed taxonomic statu s ( i .e. separation at the species level). Mauremys leprosa is the most differentiated of the three, M. caspica and M. rivulata being more closely related. Climatic changes during the Pleistocene influenced the distribution of M. rivulata and resulted in a latitudinal oscillation of the populations in a north - south direction in Greece, and consequently in a mixing of their genetic material. This hypothesis is confirmed by the absence of correlation between genetic distances and geographical origin oft he specimens studied.

Keywords: Aegean region, cytochrome b, Mediterranean, phylogeography

pp.47-49

Authors: Alfredo Salvador, José P. Vejga And Marisa Esteban

pp.51-53

Authors: Jarmo Perala