The Herpetological Journal

pp. 97-106
Authors: Tocher, Mandy D.; Fletcher, David & Bishop, Phillip J.

Abstract: A stage-structured population model was developed to predict which of nine hypothetical translocation scenarios was likely to produce the best outcome for the rare Hamilton's frog (Leiopelma hamiltoni McCulloch). Model outcome was measured in terms of population growth rate and probability of extinction. Only females were modelled. The model predicted that moving at least 20 female adult frogs was the best strategy, and moving subadult frogs alone, or no frogs at all was the worst in terms of mean growth rate of both populations combined. When the new population was considered separately, introducing subadults alone was the worst strategy in terms of mean growth rate and extinction probability. Extinction of the donor population was most likely when 40 adult females were removed, and the extinction risk was reduced when only 20 were removed. We consider the most reasonable management strategy - confirmed by the modelling and supporting qualitative data- is the translocation of 20 adult and 20 subadult female frogs (with the concurrent translocation of 40 males). This scenario provides a balance between risk of extinction in the donor population and probability of success in the translocated population.

Keywords: RELOCATION, AMPHIBIAN CONSERVATION, POPULATION VIABILITY ANALYSIS

pp. 107-113
Authors: Perera, A.; Pérez-Mellado, V.; Carretero, M. A. & Harris, D. J.

Abstract: We examined the diet of Lacerta perspicillata in populations from different localities, thus providing the first quantiative data on the diet of this species. Five continental populations in Morocco located at different altitudes and an introduced insular population were analysed during April. Our results confirm that L. perspicillata is an insectivorous species and those found at medium altitudes with comparable ecological conditions in Morocco have a similar diet. In Taza, however, both sympatric L. perspicillata forms have different diets. The most varied diets were observed at high altitude and in insular populations. Local diet variability is probably more related to different ecological conditions and, consequently, changing trophic availability than to lizard body size or other morphological or behavioural constraints. Further studies, including studies on trophic availability and seasonal variation, could confirm our preliminary results on local differences in the dietary habits of this species and the potential role of insularity.

Keywords: FEEDING ECOLOGY, ALTITUDE, INSULARITY, LACERTIDAE

pp. 115-122
Authors: Abrunhosa, Patrícia A.; Wogel, Henrique & Pombal, José P.

Abstract: Temporal distribution, reproductive mode and pattern, and calling activity were recorded for an anuran community during 13 months in a temporary pond in south-eastern Brazil. Nineteen species from four families (Bufonidae, Hylidae, Leptodactylidae and Microhylidae) were recorded at the pond. Hylidae was represented by the most species, followed by the family Leptodactylidae. The reproductive diversity of the community was represented by five reproductive modes, and three reproductive patterns (prolonged, explosive and opportunistic breeders). Reproductive temporal analysis showed an anuran succession along different conditions of the pond (dry, flooded, and drying pond), probably related to specific reproductive mode and physiological tolerance to temperature and precipitation. Leptodactylid frogs were the first breeders, reproducing before the pond filled up, followed by species that lay eggs in the vegetation above water, and lastly the largest aggregation of Hylidae took place. Stereocyclops incrassatus (Microhylidae) was the unique explosive breeder in the community, congregating in the pond just after the first heavy rain at the beginning of the rainy season. Multiple regression analysis showed that air temperature, pond depth, and weather condition were the best predictors to explain the calling activity in anuran species. Hylid and leptodactylid frogs responded in a different way to environmental factors: in general, positive associations for hylid frogs, and negative associations for leptodactylid frogs. There were also species-specific differences in chorus attendance related to environmental factors within each family.

Keywords: REPRODUCTIVE PATTERN, COMMUNITY, ANURA, SUCCESSION, BREEDING PATTERNS

pp. 123-132
Authors: Campos, Zilca; Coutinho, Marcos; Mourão, Guilherme; Bayliss, Peter & Magnusson, William E.

Abstract: Movement patterns of caimans were studied over a 16-year period in two areas of the Brazilian Pantanal, one dominated by intermittent rivers and another, adjacent region of many isolated lakes. We marked caimans in 100 lakes (1986–2001) and two rivers (1987–1999). We recaptured 163 adult males, 132 adult females and 237 juveniles. In a two-year interval, hatchlings moved only within the lake area or within the river area and the maximum distance moved was 6.0 km (mean=0.5 km, SD=1.0) in the lake area, and 1.25 km (mean=0.6 km, SD=0.3) in the river area. In a period of one year, females and males larger than 40 cm snout-vent length moved similar distances in both areas (max.=9.8 km). We monitored 47 adult caimans by radio-telemetry in the river area for about a year. The size of the area used by telemetered individuals over periods of 30 to 436 days varied from two to 1649 ha. The areas used by five males in sites subjected to experimental hunting were similar to those used by five other males in areas not subjected to hunting. In periods of 1–5 years, females and males larger than 40 cm SVL moved maximum distances of 16 and 18 km, respectively. Five individuals marked as hatchlings in the lake area were recaptured as adults after intervals of 5–15 years. The extensive long-term and short-term movements by caimans mean that individual ranches should not be considered independent management units for sustained use of caimans in the Pantanal.

Keywords: MOVEMENT, CROCODILIAN, DISPERSAL, POPULATION MANAGEMENT

pp. 133-148
Authors: Roitberg, Evgeny S. & Smirina, Ella M.

Abstract: Age and growth in Lacerta agilis (ssp. L. a. boemica) and a closely related sympatric species L. strigata from the eastern North Caucasus, Russia were assessed by skeletochronology and back-calculation methods. We examined 320 specimens from one lowland, two submontane (both species), and two mountain (L. agilis) localities. Age structure, back-calculated snout-vent length (SVL) at hatching and subsequent hibernations, and asymptotic SVL were studied for sexual dimorphism, altitudinal variation and interspecific differences. Pattern of resorption of growth layers in bone and its possible effects on growth inferences from skeletochronological data were also considered. The back-calculated SVLs showed a good conformity to comparable field data. Mean and maximum SVL at the first hibernation clearly decreased with altitude. Within the same localities, these parameters were consistently higher in L. agilis than in L. strigata. Between the 1^st and 2^nd hibernations (the period of the highest increment in SVL in all study populations), L. strigata grew faster than the syntopic L. agilis. In the lowland locality, females of both species tended to grow slower than males between the 1^st and 2^nd hibernations, while at higher elevations they exhibited lower SVL increments than the males between the 2^nd and 3^d hibernations. This pattern, along with occurrence of gravid yearlings in the lowland locality (but not in the other sites), suggests an earlier onset of reproduction in the lowland populations compared to those from higher elevations. Asymptotic SVLs in the study populations tended to be larger in males than in females. In L. agilis these sexual size differences (SSD) varied among populations, being quite strong in the lowland site and negligible at the highest locality. The mountain populations (960 and 1900 m a.s.l.) of L. a. boemica exhibited higher mean age and longevity than the lowland and submontane populations (20-600 m a.s.l.) of both species; however, no clear altitudinal trend was found for adult SVL. Much of the variation revealed in this study, including the interlocality differences in SSD, can be related to the length of activity season, in line with recently published theoretical models and experimental studies stressing the role of proximate factors.

Keywords: SEXUAL SIZE DIMORPHISM, LIZARDS, LIFE-HISTORY, ALTITUDINAL VARIATION, ASYMPTOTIC SIZE

pp. 149-162
Authors: Candioti, M. Florencia Vera

Abstract: Ecomorphological guilds for anuran larvae are based on developmental modes, external morphology and habitat. Furthermore, several authors have investigated relationships between internal morphology and ecological habits. However, the relationships between internal morphology and tadpole ecological habits are not well established. In the present paper the quantitative methodology of geometric morphometrics is applied to look for correlation between the anatomy hyobranchial skeleton and the ecology of anuran larvae. Tadpoles of 14 species belonging to six different ecomorphological guilds were studied. The specimens were cleared and stained, and the hyobranchial apparatuses removed and drawn in ventral view. To record the shape variation, landmark-based geometric morphometric methodology was applied, involving a Relative Warp Analysis followed by multivariate statistics. Results show that species classify into four significantly different groups, according to their hyobranchial apparatus shape. Macrophagous tadpoles have well-developed ceratohyals and hypobranchial plate developed, and branchial baskets highly reduced. Generalized tadpoles have a large ceratobranchial area, with the hypobranchial plate covering a smaller area. Microphagous tadpoles have a very developed and complex branchial basket, and their hypobranchial plates are strongly reduced. Megalophagous tadpoles have the ceratohyals laterally expanded. These four groups are in general maintained after the inclusion of more species from the literature. Morphological groups can be related to size of food particles consumed, from very large in megalophages and macrophages, to very small, in highly efficient microphages.

Keywords: TADPOLE, FROG, HYOBRANCHIAL SKELETON, FEEDING HABIT, MORPHOLOGY

pp. 163-169
Authors: Kusano, Tamotsu; Sakai, Aki & Hatanaka, Sumio

Abstract: Using both field observations and laboratory experiments, thermal and nutritional functions of the arboreal foam nests of the Japanese treefrog Rhacophorus arboreus were examined in early summer in the years 2000–2002. The temperature at the centre of the nests and ambient air temperature were monitored using a data logger in the field for several days. The results showed thermal regulation by the foam mass; the inside of the nests was maintained up to 6°C cooler by the foam masses when the ambient temperature was high (>25°C). Laboratory experiments also showed that hatching success of the embryos was very low at high temperatures (near 30°C). The insulation effect of the foam nests is, therefore, considered to be adaptive for R. arboreus. Hatchling growth was examined for a week under different food conditions: water only (no food), foam mass and boiled lettuce. Larvae showed no significant growth without food, but they grew to be 2–5 times heavier in dry body mass than hatchlings when supplied with foam mass or boiled lettuce. Foam mass proved to be at least as effective as boiled lettuce as a food for hatchlings. The present study demonstrates the thermal and nutritional effects of the foam nests of R. arboreus.

Keywords: AMPHIBIA, THERMAL ADVANTAGE, NUTRITIONAL EFFECT, HATCHING SUCCESS

pp. 171-176
Authors: Martins, Marcio

Abstract: The semi-aquatic teiid lizard Crocodilurus amazonicus (local name jacarerana) inhabits lakes and rivers throughout Amazonia. Although it is a common species in many areas, very little information is available on its biology. I provide information on the ecology of C. amazonicus in areas of flooded forests in central Amazonia, Brazil. Most field observations were made at two igapó (blackwater swamp) forest in the Negro River basin, from 1992 to 1995. Lizards were found accidentally or during time-constrained searches by boat or on foot. More than 100 individuals were observed in both areas. Lizards were either swimming in shallow waters or exposed on the ground or on low vegetation. During low water, when large expanses of shoreline became exposed, C. amazonicus foraged and basked on these margins. When the water began to rise and several ponds were formed in the igapó forests, the lizards moved into the flooded forest. They were much easier to find during low water. The jacarerana feeds on several prey types, but eats more crustaceans and other aquatic animals than terrestrial teiids. I found 85 prey items in 26 stomachs. Arthropods (insects, shrimps, crabs and spiders) comprised about two thirds of total prey volume and vertebrates (fish and frogs, including tadpoles) about one third. Because most prey were aquatic, C. amazonicus probably forages mainly in the water. The jacarerana may be the only Neotropical lizard that feeds frequently on fish (23% of total prey volume) and crabs (16%). The occurrence of C. amazonicus in many protected areas in Brazil and adjacent countries may offset population declines associated with development in the future.

Keywords: TEIIDAE, AMAZONIA, AQUATIC LIZARD, PISCIVORY, SWAMP FOREST

pp. 177-182
Authors: Pleguezuelos, Juan M. & Feriche, Mónica

Abstract: Organisms that produce more than one newborn at every reproductive event must choose between two options with respect to their reproductive output: to produce a few large or many small young. The decision will be influenced by the spectrum of prey sizes available to young. The ladder snake (Rhinechis scalaris), a heavy-bodied Mediterranean colubrid, is well suited for the study of its reproductive ecology under this cue: the species consumes only endothermic prey and, thereafter, hatchlings of this gape-size-limited predator must be large enough to prey on small mammals. We analysed the reproductive ecology of this species, a quasi-endemic to the Iberian Peninsula, by studying a large sample of specimens collected in the south-eastern Iberian Peninsula. Most adult females (83.3%) reproduced in sequential years, with vitellogenesis beginning in early spring, and oviposition occurring in the first half of July. In contrast to the general rule for most temperate snakes, no depletion in fat bodies was observed during the period of vitellogenesis, females exhibiting a very high level of fat-body reserves throughout all months of the activity period. When compared with other Mediterranean species, hatching occurred very late in the activity season (October), newborns were rather heavy bodied, with very high fat-body levels, and apparently did not feed until the following spring. From our dataset, we suggest that female R. scalaris produce hatchlings large enough to enter hibernation without feeding, perhaps increasing in this way the survival rate of juveniles in their first calendar year. They probably need to devote their reserves at hatching to growth and to better face their first, bulky prey.

Keywords: HATCHING TIME, HATCHLING SIZE, COLUBRID, FAT BODIES

pp. 183-189
Authors: Köhler, Jörn; Bwong, Beryl A.; Schick, Susanne; Veith, Michael & Lötters, Stefan

Abstract: A new species of arboreal Leptopelis is described from Kakamega Forest, western Kenya. It is a small, brown forest species formerly referred to L. modestus, but distinguished by differences in advertisement call and the sequence of the mitochondrial 16S rRNA gene. The specific allocation of certain related populations of Leptopelis in East and West Africa is briefly discussed.

Keywords: BIOACOUSTICS, TAXONOMY, AMPHIBIA, DNA, SYSTEMATICS

pp. 191-201
Authors: Tomovic, Ljiljana

Abstract: Geographic variability of the nose-horned viper (Vipera ammodytes) was analysed using multivariate techniques in order to clarify the taxonomic status and geographic ranges of the subspecies. Analyses included samples ranging from central northern Italy and southern Austria to easternmost Turkey, Georgia and Armenia, and hence, all described taxa. In total, 14 morphometric, five meristic and nine qualitative traits of 922 specimens (451 males and 471 females) were recorded and analysed using different multivariate statistics. The results showed the validity of four subspecies: one inhabiting the western and central parts of the species' range (from Italy, via Austria, to the western and central parts of the Balkans), the second occurring in the southernmost part of the Balkan peninsula, the third distributed from the southern and eastern Balkans to western Turkey and the fourth inhabiting eastern Turkey, Georgia and Armenia.

Keywords: SNAKE, MULTIVARIATE ANALYSES, BALKANS, SUBSPECIES

pp. 203-211
Authors: Alcalde, L. and Natale, G. S. and Cajade, R.

Abstract: This paper describes the external and buccopharyngeal morphology, chondrocranium and cranial muscles in tadpoles of Physalaemus fernandezae. The data are compared with those for other species of Physalaemus to improve the diagnosis of the species group within the genus. Species of the P. biligonigerus group have four infralabial papillae, two semicircular arches of pustulations in a V-shaped pattern on the prenarial arena, 6–8 conical papillae and 40–60 pustulations on the buccal roof arena, four postnarial papillae, a semicircular median ridge, claw-shaped lateral ridges and larval crista parotica with a poorly-developed anterior process. Species of the P. pustulosus group possess four infralabial papillae (shared with the P. biligonigerus group), tooth row formula 2(2)/3, four lingual papillae, two postnarial papillae, twelve conical papillae and 16–20 pustulations on the buccal roof arena, short lateral ridges with rough concave margins and larval crista parotica with a well-developed anterior process and reduced posterior process. Species of the P. cuvieri group present two infralabial papillae, three pustulations and two serrated papillae on the prenarial arena, five pustulations and two serrated papillae on the postnarial arena, four long and bifid papillae and more than 60 pustulations on the buccal roof arena, and lack larval crista parotica. In species of the P. signiferus group both medial and lateral mental gaps are absent, and the tooth row formula is 2(2)/3(1).

Keywords: LARVAE, AMPHIBIAN, MUSCULATURE, FROG, MORPHOLOGY

pp. 213-220
Authors: Giraudo, Alejandro R.; Arzamendia, Vanesa & Cacciali, Pier

Abstract: We analyzed geographic variation in southern populations of Liophis miliaris and tested the hypothesis that L. m. semiaureus is a valid species. We examined 222 specimens from Argentina and Paraguay, including those from the areas of overlap of L. m. semiaureus and L. m. orinus, and compared these data with previous taxonomic revisions. We performed univariate statistical tests comparing L. m. semiaureus and L. m. orinus, and a discriminant function analysis using three morphological variables to compare four subpopulations, including two of L. m. semiaureus and two of L. m. orinus. We examined coloration in life in 152 specimens. These data and analyses support the hypothesis of L. semiaureus as a valid species: univariate analyses show significant differences in ventral and subcaudal numbers, and snout-vent length/tail length ratio between the two putative subspecies. L. m. semiaureus has significant more ventrals and subcaudals than L. m. orinus. Discriminant analysis separated two defined populations corresponding to L. m. orinus and L. m. semiaureus. Populations of L. m. semiaureus that are in contact with L. m. orinus populations show the highest ventral values of all of the L. m. semiaureus populations examined by us. We recorded differences in coloration among the juveniles of both subspecies, including specimens from neighbouring localities. The distributions are parapatric and have different ecological and historical settings. We discuss the validity of some diagnostic characters that have been used to distinguish L. m. semiaureus.

Keywords: GEOGRAPHIC VARIATION, SNAKE, LIOPHIS MILIARIS SEMIAUREUS, TAXONOMY

pp. 221-227
Authors: Canestrelli, Daniele; Zangari, Francesca & Nascetti, Giuseppe

Abstract: Genetic variation in 12 populations of the Italian endemic spectacled salamander Salamandrina terdigitata was investigated through the analysis of 29 allozyme loci. Two well-differentiated population groups were identified, one ranging from the Tusco-Emilian Apennine to southern Latium, the other comprising populations from central Campania to Calabria. Nine diagnostic and four highly differentiated loci led to an average genetic distance of D_Nei=0.47 between the two groups, while within them D_Nei ranged from 0.00 to 0.05. The observed genetic structure strongly suggests that two distinct species have so far been included within Salamandrina terdigitata. The names Salamandrina perspicillata (Savi, 1821) and S. terdigitata (Bonnaterre, 1789) are here proposed for the species from central and southern Italy respectively.

Keywords: MOLECULAR TAXONOMY, CRYPTIC SPECIES, CAUDATA, ITALY

pp. 229-231
Authors: Razzetti, Edoardo; Sacchi, Roberto & Platz, James E.

Abstract: Vocalizations of Rana italica from six adult males were obtained from Torrente Gentile, a small brook located in the Torrente San Siro basin, Santa Margherita Ligure (Northern Italy). All signals were propagated from the bottom of shallow pools and were inaudible in air. Two common and one rare call type were documented. All calls were short, low amplitude signals. The most common call is frequency modulated, harmonically rich and the other two are not. None exceed 0.26 s. Our study confirms that males call underwater. This is consistent with the conclusion that it has an underwater mate recognition system.

Keywords: UNDERWATER PROPAGATION, REPRODUCTIVE BEHAVIOUR, VOCALIZATIONS, FROG