Stable or plastic body shape? Emys orbicularis hatchlings-juveniles growth patterns under different ecological conditions

To test if habitat could shape shell features of freshwater turtles starting from birth, we tested hatchlings of Emys orbicularis, randomly chosen from four clutches of the same locality, under two treatments, stagnant (pond habitat) vs lotic (river habitat) water regimes. Due to mortality at the beginning of the experiment, we finally considered only two clutches. Turtle shells were characterized initially at hatching and then after one year of treatment by means of traditional and geometric morphometrics, and phenotypic trajectories analyses were conducted on both types of data. Carapace growth was isometric both in proportion and shape, while plastron showed an allometric pattern: length increased more than width, while the contour showed an expansion at the rear and a compression of the front. The hydrodynamic conditions during growth did not seem to affect the phenotypic trajectories of the shell proportions or the plastron. On the contrary, a significant effect was found on the phenotypic trajectory of the carapace: the size component (but not the angle one) was positively influenced by the "lentic" treatment, suggesting a different growth rate between the two environmental conditions

Dimorphisme sexuel, morphométrie et variation phénotypique de la Couleuvre verte et jaune Hierophis viridifl avus dans une région du centre de la Méditerranée

Animal populations living in different environments generally exhibit divergent phenotypic characteristics. In snakes, body size varies greatly among disjunct populations. The European Whip snake, Hierophis viridifl avus, is widely distributed in the western Mediterranean area, and on most of both small and large islands of the Tyrrhenian Sea. We compared biometrical patterns regarding ventral scalation, body size and head size among different samples from mainland, large islands and small islands. Sexual Size Dimorphism was very marked in the species, with males attaining larger body size and larger relative head size than females and a lower number of ventral scales. There was a clear evidence of a strong relationship between ventral scale number and the geographic origin, with smaller island snakes characterized by a signifi cantly higher number of ventral scales. This relationship was true even when considering body size, with insular snakes signifi cantly smaller than mainland ones. Our results clearly indicated a strong differentiation among the considered populations, and provided basis to clarify the relative importance of phenotype variationDimorphisme sexuel, morphométrie et variation phénotypique de la Couleuvre verte et jaune Hierophis viridiflavus dans une région du centre de la Méditerranée. - Généralement les populations animales qui vivent dans des environnements différents divergent dans leurs caractéristiques phénotypiques. Chez les serpents, la taille corporelle varie fortement entre populations disjointes. La Couleuvre verte et jaune Hierophis viridiflavus est largement distribuée en Méditerranée occidentale et sur les îles tant petites que grandes de la mer Tyrrhénienne. Nous avons comparé les patterns biométriques relatifs à l'écaillure ventrale, la taille du corps et de la tête dans divers échantillons provenant du continent, de petites et de grandes îles. Le dimorphisme sexuel est très marqué chez cette espèce, les mâles étant corporellement plus grands, avec une tête plus grosse et moins d'écailles ventrales que les femelles. Une relation forte entre le nombre d'écailles ventrales et l'origine géographique a été clairement mise en évidence, les individus provenant des petites îles étant caractérisés par un nombre significativement élevé d'écailles ventrales. Cette relation se maintient quand on prend en compte la taille corporelle, les individus insulaires étant plus petits que ceux du continent. Nos résultats indiquent clairement une forte différenciation entre les populations étudiées et éclairent l'importance relative de la variation phénotypique

Subjective resource value affects aggressive behavior independently of resource-holding-potential and color morphs in male common wall lizard

AbstractGame theory models predict the outcome of a dyadic contest to depend on opponents' asymmetries in three main traits: resource-holding potential (RHP), resource value (RV) and aggressiveness. Using male common wall lizards Podarcis muralis, a polymorphic species showing three discrete morphs (white, yellow, and red), we investigated how the aggressive behavior varies according to a change in subjective RV and color morphs, while controlling for the asymmetry in RHP (using mirrors). By comparing the aggression of the same individual towards its mirror image in two different arenas (familiar = high subjective RV; novel = low subjective RV), we showed that lizard aggressive behavior was more intense and prolonged in the familiar arena than in the new one, thus supporting the occurrence of a direct relationship between motivation and aggression in this species. We also found the overall aggressiveness to differ from individual to individual, supporting the general hypothesis that aggressiveness is a trait associated with personality. By contrast, no effect of morphs was detected, ruling out the occurrence of morph specific variation in the aggressiveness. Our results highlight that an individual's motivation and personality might be as important as RHP and RV in the resolution of animal contests

The "Peer" in "Peer Review"

Gad Perry1, Jaime Bertoluci2, Bruce Bury3, Robert W. Hansen4, Robert Jehle5, John Measey6, Brad R. Moon7, Erin Muths8, and Marco A. L. Zuffi9,* 1 Texas Tech University, Lubbock, TX, USA; Journal of Herpetology. 2 Universidade de Sao Paulo, Brazil; Phyllomedusa. 3 USGS, Corvallis, OR, USA; Herpetological Conservation and Biology. 4 Clovis, CA, USA; Herpetological Review. 5 University of Salford, Greater Manchester, UK; Herpetological Journal. 6 University of the Western Cape, South Africa; African Journal of Herpetology. 7 University of Louisiana at Lafayette, LA, USA; Herpetologica. 8 USGS, Fort Collins, CO, USA; Journal of Herpetology. 9 Museum Natural History, University of Pisa, Italy; Acta Herpetologica

Evaluating taxonomic inflation: towards evidence-based species delimitation in Eurasian vipers (Serpentes: Viperinae)

International audienceThe designation of taxonomic units has important implications for the understanding and conservation ofbiodiversity. Eurasian vipers are a monophyletic group of viperid snakes (Serpentes, Viperinae), currently comprising fourgenera (Daboia, Macrovipera, Montivipera and Vipera) and up to 40 species. Taxonomic units have been described usinga wide variety of methods and criteria, and consequently, considerable controversy still surrounds the validity of somecurrently listed species. In order to promote a consensus- and evidence-based taxonomy of Eurasian vipers, we analysedpublished mitochondrial and nuclear DNA sequences for this group to reconstruct phylogenetic relationships among currentlyrecognized viper species.We also compiled information on external morphology to assess their morphological distinctiveness.Phylogenetic inference based on mtDNA sequences shows contrasting levels of divergence across genera and species andidentifies several instances of non-monophyly in described species. Nuclear DNA sequences show extremely low levels ofgenetic variation, with a widespread pattern of allele sharing among distant species, and even among genera. Revision ofmorphological data shows that most species designations rely on scalation traits that overlap extensively among species ofthe same genus. Based on our combined assessment, we recognize 15 taxa as valid species, three taxa which likely representspecies complexes, 17 taxa of doubtful validity as species, and five taxa for which species status is maintained but furtherresearch is highly recommended to assess taxonomic arrangements. We stress the need to implement integrative taxonomicapproaches for the recognition of evidence-based taxonomic units in Eurasian viper

Diet and morphometrics of Coluber (=Hierophis) viridiflavus on the island of Montecristo (Tyrrhenian Sea, Italy)

In this short note I present and discuss new data on diet and additional natural history data for Coluber (=Hierophis) viridiflavus

Italian subspecies of the asp viper, Vipera aspis: Patterns of variability and distribution

The asp viper, Vipera aspis, is distributed in western Europe and comprises several morphological subspecies other than the nominal form, V. a. aspis of northern to southern France: V. a. zinnikeri, V. a. atra, V. a. francisciredi, V. a. hugyi. Each form is very often distinguishable, both by dorsal colour pattern and number of ventral scales. Examining a balanced sample for each subspecies and each sex from Italy and other areas, we found that the distributive patterns of Italian populations are as follows: V. a. atra is widely distributed throughout northwestern Italy, reaching the Ligurian Sea coasts; it passes westwards into France up to most of the Haute Provence region, turning northwards up to the Savoie region. Instead, V. a. francisciredi extends eastwards throughout the Po plain and southwards to southern Italy. The distribution limit of V. a. hugyi extends from northern Apulia southwards to the Irpini mountains, and the slopes of Mt. Vesuvius volcano, and the remaining part of Italy and Sicily. Most of the known morphological differences between aspis and francisciredi do not seem to be consistent. The subspecies montecristi is identical to hugyi. Some hypotheses of possible causes of different distributive patterns are presented

Similarities and differences in adult tortoises: a morphological approach and its implication for reproduction and mobility between species

Sexes in Chelonia display marked differences. Sexual size dimorphism (SSD) is important in evolutionary biology. Different sexual strategies result in species specific selection. Biometric variation in male and female tortoises of two species is studied. Eighteen biometrics were measured in 75 museum specimens (20 Testudo graeca; 55 T. hermanni). Nine of 18 parameters in T. hermanni and two of 18 in T. graeca were sexually dimorphic. Multivariate analyses (principal component analysis) highlighted two components, with bridge length the first and anal divergence the second component. The bridge length can be used to separate sexes and species. Males of both species were most different, whereas females of two species overlapped in body shape measurements. We hypothesise that female similarity could be a by-product of reproductive biology and sexual selection that optimise individual fitness

An Integrated Approach to the Study of the Diet of Vipera aspis

Integrated approach on the diet of the Asp Vipe

Large scale phenotypic characterisation of Hierophis viridiflavus (Squamata: Serpentes): climatic and environmental drivers suggest the role of evolutionary processes in a polymorphic species

Colour variability is largely widespread in the animal world as it is tightly associated with fitness and survivorship. Therefore, the drivers and implications of such variability have been of great interest for zoologists in the past decades. Reptiles are excellent models to investigate colour variations and expression under different conditions. Here, we focused on melanism occurrence in the two main lineages of Hierophis viridiflavus at the scale of the species distribution, by extracting available data from iNaturalist, a citizen science network, with the aim of detecting any pure effect of climate or local habitat on colour expression. Our analyses highlighted that habitat does not explain differences in phenotypes, whereas marked effects of geographic and climatic variables were detected. However, the observed climatic effects could be a proxy of the geographical distribution of the two groups, and thus the high occurrence of bright colourations in western populations of the eastern lineage could be addressed to an ongoing event of asymmetric gene flow in contact zones. The current distribution of phenotypes could be the outcome of the evolutionary history of the species combined with the geological history of the Mediterranean region. This investigation, though, is only preliminary and molecular analyses on highly variable regions of the genome are mandatory to address this issue