The Herpetological Journal

pp. 219-224
Authors: Burghelea, Carmen I.; Zaharescu, Dragos G. & Palanca-Soler, Antonio

Abstract: Amphibians are sensitive indicators of habitat degradation. Understanding their dietary patterns in altered landscapes is fundamental to understanding the effects of habitat loss worldwide. A stomach content analysis was conducted on Pelophylax perezi, an endemic anuran heavily colonizing rice fields in Monegros, an arid region in northeast Spain. The taxonomic range of prey consumed by this species was compared with prey availability and dietary changes were evaluated among frog size groups. Small adult insects (dipterans, coleopterans, ants and heteropterans) were the main diet, indicating an active foraging mode. Frogs showed no preference for any prey taxa. Larger frogs consumed a higher volume of food, but relatively fewer prey than smaller individuals. A large niche breadth was recorded for all groups. Food partitioning was lowest between distant size groups. Maximum prey size was significantly related to morphological constraints such as frog size and mouth width. Bigger frogs preyed on larger items while also foraging on smaller ones, indicating no prey size selection. Overall, P. perezi had a generalist feeding pattern dictated mainly by prey availability. These food habits may help the species to persist in the agricultural landscape of this arid region.

Keywords: ELECTIVITY, RICE PADDIES, MONEGROS ARID REGION, NICHE BREADTH, PREY SIZE SELECTION, DIET

pp. 225-229
Authors: Khannoon, Eraqi; Breithaupt, Thomas; El-Gendy, Afaf & Hardege, Jörg D.

Abstract: Femoral glands of lizards are holocrine structures that produce compounds used by lizards in intraspecific communication. Here we show that the femoral gland secretions of a lacertid lizard, Acanthodactylus boskianus, contain chemicals that elicit sex-specific responses. These glands are found in both males and female A. boskianus. We used the secretions of both sexes as stimuli presented on cotton swabs. Tongue flicks as well as other behavioural responses of both male and female lizards were recorded over a 60 second interval. Both males and females increased their tongue-flick rate towards male secretions, and some males bit swabs containing male secretions. Only a small proportion of females (25%) showed a similarly aggressive response. Female secretions only elicited elevated tongue-flick frequencies in males and did not elicit any aggressive behaviour. As a result of male–male competition and mate choice, the secretions appear to play a role in male territorial behaviour and in sex recognition, which could, for example, reduce the cost of male–male aggression when competing for females. This work opens future opportunities to test the role of chemical cues in mate choice and dominance hierarchies in lizards.

Keywords: LACERTIDAE, SQUAMATA, AGGRESSION, LIZARD, CHEMICAL COMMUNICATION, SEXUAL BEHAVIOUR, PHEROMONES

pp. 231-236
Authors: Velasco, Julián Andrés; Gutiérrez-Cárdenas, Paul David A. & Quintero-Angel, Andrés

Abstract: We describe a new species of the Anolis aequatorialis group from the central Andes of Colombia. The new species, Anolis anoriensis, is similar to A. eulaemus Boulenger, which occurs in both the western and central Andes, and was positioned in the eulaemus subgroup of the aequatorialis group. Anolis anoriensis differs from A. eulaemus in having smaller interparietal scales and a green body coloration with a darker anterior part of the dewlap. We also for the first time describe the coloration of Anolis eulaemus, which is almost exclusively brown with a diffused light brown dewlap.

Keywords: MORPHOLOGY, ANOLIS ANORIENSIS SP. NOV, TAXONOMY

pp. 237-241
Authors: Jones, Christopher & Bell, Trent

Abstract: There has been much debate about the use and acceptability of toe-clipping as a means of permanently marking reptiles and amphibians during scientific surveys. Trapping studies of reptiles and amphibians are frequently, although not always, compromised by low probabilities of recapture of individuals following their initial capture and marking. Low recapture rates can influence the precision of estimates of population size and home range that are derived from trapping data. We investigated whether there was a difference in the short-term probability of recapture of toe-clipped McCann's skinks (Oligosoma maccanni) compared with those marked non-invasively with a pen. We pitfall-trapped skinks for seven days in a dry scrub habitat on the South Island of New Zealand. On first capture, skinks were individually marked by either toe-clipping or writing a code on their ventral surface with a silver marker pen. The resulting recapture histories for 118 skinks were analysed using Huggins' closed-population models in the MARK program. The best supported models indicated that recapture probability was significantly affected by sex (females > males) and previous toe-clipping experience (previously clipped > not). There was no support for an effect of marking method on short-term recapture probability, which is likely to be affected by other sampling factors such as trap spacing, social behaviour or response to handling. Females' higher recapture probability may reflect their increased energetic requirements during the breeding season, making them more likely to enter traps in search of food. We speculate that previous experience of toe-clipping is a surrogate for age and social dominance leading to increased access to traps.

Keywords: MARK-RECAPTURE, MARKING METHODS, OLIGOSOMA SPP

pp. 243-248
Authors: Robles, Cecilia I. & Halloy, Monique

Abstract: Investigating space use in animals and determining the amount of overlap with neighbours may help to understand whether territoriality is part of a social system, and can help in inferring possible reproductive strategies of males and females. Here we examine these issues in the lizard Liolaemus quilmes from northwestern Argentina based on space use of core areas. We studied a population comprising 119 #large# (LA) and 52 #small# (SA) adults over two consecutive years. We compared core areas of males and females during the reproductive and post-reproductive season, documenting the occurrence and amount of overlap among core areas. We found that the average size of core areas of both LA and SA individuals did not significantly differ from each other across two study years. However, LA male core areas were significantly larger than those of LA females, and LA male core areas were significantly larger than those of SA males. LA and SA male core areas were significantly larger during the reproductive than during the post-reproductive season, possibly indicating the need of males to gain access to females. SA females had significantly smaller core areas during the reproductive season than during the post-reproductive season, whereas LA female core areas were not different between seasons. The amount of core area overlap among males did not exceed 23%, supporting the idea of territory defence. Female core areas did not overlap. The core areas of LA males and females overlapped with up to two females and three males, respectively, suggesting a polygynandrous mating system.

Keywords: LIOLAEMIDAE, REPRODUCTION, SAPTIAL DISTRIBUTION, SAURIA, CORE AREAS, IGUANIA

pp. 249-259
Authors: Hsiou, Annie S. & Albino, Adriana M.

Abstract: We report new snake vertebral remains originating from the late Miocene of south-western Brazilian Amazonia (Solimões Formation) and the middle–late Miocene of Venezuela (Socorro and Urumaco Formations). The Brazilian material was attributed to Boidae (aff. Epicrates sp. and Waincophis sp.) and to two probably undetermined #Colubridae#. The new snake vertebrae from Venezuela are referred to the extant boid Eunectes sp.. Known specimens from the middle Miocene of Venezuela (Socorro Formation) are re-evaluated as cf. Eunectes. Until now, South American late Miocene squamate records have been reported only from Argentina and Venezuela. We present the first record in the Neogene of Brazil, considerably increasing our knowledge of the South American herpetofauna.

Keywords: #COLUBRIDAE#, VENEZUELA, URUMACO FORMATION, BOIDAE, SOLIMOES FORMATION, BRAZIL, SOCORRO FORMATION

pp. 261-269
Authors: Peltzer, Paola M.; Attademo, Andrés M.; Lajmanovich, Rafael C.; Junges, Celina M.; Beltzer, Adolfo H. & Sanchez, Laura C.

Abstract: The conversion of forests to agroecosystems presents a challenge for biodiversity conservation. In this study, the feeding habits of three species of anurans (Rhinella fernandezae, Odontophrynus americanus and Physalaemus albonotatus) were compared between a soybean field and a native forest in Santa Fe Province, Argentina. Our dietary assessment is based on 124 individuals (47 R. fernandezae, 45 O. americanus and 32 P. albonotatus). Lepidopteran larvae were the predominant item in anuran diets from the soybean field, whereas collembola, isopods and snails prevailed in the diets from forests. Generally, the three anuran species shifted their diets as prey differs in the two environments, but R. fernandezae and P. albonotatus maintained a preference for a few prey types. Mean niche overlap in the soybean field was smaller than expected by chance, suggesting that the three anuran species are competing for limited resources. Trophic studies on other native anurans in agroecosystems should be a priority in conservation efforts due to their potential use as natural control agents, as well as for assessing the consequences of the broad conversion of natural forest to agricultural use in our region and throughout the world.

Keywords: PHYSALAEMUS ALBONOTATUS, TROPHIC NICHE, DIET, RHINELLA FERNANDEZAE, ODONTOPHRYNUS AMERICANUS, AGRICULTURE

pp. 271-275
Authors: Jarvis, Laurence E.

Abstract: Predatory fish have negative impacts on many amphibian populations, often through direct predation on embryos and larvae. The presence of predators during embryonic development may elicit adaptive responses in emerging larvae. This study examined the non-consumptive effects of predatory three-spined sticklebacks (Gasterosteus aculeatus) on great crested newt (Triturus cristatus) embryos under controlled conditions. Embryos raised in the presence of sticklebacks but in predation-proof enclosures suffered significantly higher mortality compared to control treatments in three independent trials over two years. Overall 26.9% of embryos hatched in stickleback treatments compared to 47.6% from controls. As sticklebacks were treated with fungicide before the experiments, this difference in mortality is unlikely to be due to fungal disease transmission. There were no significant differences in the date, stage of development or size at hatching in larvae raised with and without sticklebacks. The results suggest the potential for negative non-consumptive impacts of predatory sticklebacks on great crested newts during the embryonic stage.

Keywords: PREDATOR CUES, FISH KAIROMONES, MORTALITY

pp. 277-280
Authors: Tozetti, Alexandro M.; Pontes, Gláucia M.F.; Borges-Martins, Márcio & Oliveira, Roberto B.

Abstract: We examined substrate temperature preferences of the South American hognose snake (Xenodon dorbignyi) in the field and in the laboratory. Individuals captured in the field were placed in a thermal gradient chamber, where they preferred temperatures averaging 32.8 °C and avoided substrate temperatures below 10.5 °C and above 37.5°C. The mean body temperatures of snakes exposed to the thermal gradient was 23.4 °C, which was similar to field measurements. Gravid females had higher temperatures than males. In the experimental chamber, X. dorbignyi remained above ground even when exposed to extremely high or low temperatures. Our results corroborate the hypothesis that X. dorbignyi is a thermal generalist that uses a broad range of substrate temperatures, representing an adaptation to the large variation in daily temperatures in sand dunes with few shelters above ground.

Keywords: SUBSTRATE SELECTION, SNAKES, THERMOREGULATION

pp. 281-284
Authors: Cornu, Cyrille & Raxworthy, Christopher John

Abstract: Standing's day gecko Phelsuma standingi is one of the largest and yet most poorly studied geckos in Madagascar. We report the discovery of a substantial northern range extension and document a previously unrecognized association between this gecko and baobab trees in southwest Madagascar. At three survey sites we found P. standingi associated with three baobabs: Adansonia grandidieri in northwest Morombe, A. rubrostipa at Ranobe and A. za at Zombitse Reserve. Although P. standingi is not an obligate baobab tree specialist, these massive trees appear to offer secure refuge and climbing surfaces, and baobabs are the main microhabitats occupied by these large day geckos. This unrecognized gecko–baobab association might partly explain why so few field observations have been made previously for P. standingi.

Keywords: REPTILIA, ADANSONIA, GEKKONIDAE