1,721,052 research outputs found
L'erpetofauna delle Riserva Naturale di Bosco Nordio
No full textWe report the results of the qualitative census on the Reptiles and Amphibians of the
Bosco Nordio (113 ha), a Natural Reserve near the mouth of the river Adige. This study was
a part of the reintroduction project of the Emys orbicularis within the Natural Reserve, and
was carried out from June to July 2003. Amphibians were checked in all ponds and ditches
of the Reserve, while Reptiles were searched along wood edges and open areas. The community
of the Bosco Nordio, before the reintroduction of the E. orbicularis, was composed
by 6 species of Amphibians (Triturus carnifex, Bufo bufo, Hyla intermedia, Rana synklepton
esculenta, R. dalmatina and R. latastei) and 7 species of Reptiles (Testudo hermanni,
Anguis fragilis, Lacerta bilineata, Podarcis muralis, P. sicula, Hierophis viridiflavus and
Natrix natrix). Despite the high number of species, most of them seems to be represented
by very few individuals
Annotated checklist and distribution of the Socotran Archipelago Herpetofauna (Reptilia)
No full textRazzetti, Edoardo, Sindaco, Roberto, Grieco, Cristina, Pella, Francesca, Ziliani, Ugo, Pupin, Fabio, Riservato, Elisa, Pellitteri-Rosa, Daniele, Butikofer, Luca, Suleiman, Ahmed Saeed, Al-Aseily, Badar Awadh (2011): Annotated checklist and distribution of the Socotran Archipelago Herpetofauna (Reptilia). Zootaxa 2826: 1-44, DOI: 10.5281/zenodo.27727
Preliminary data on the diet of Chalcides chalcides (Squamata: Scincidae) from Northern Italy
No full textThe diet in skinks is known mainly for extra-European species, especially from Australian ones, where these lizards are represented by a great number of species, while, in comparison, data for species from other continents are scarce. The three-toed skink, Chalcides chalcides, is found in a restricted part of northern Africa and in Italy, where it is distributed almost uniformly throughout the peninsula and on the major islands. Although it is well studied for aspects such as morphology and ecology, data concerning trophic preferences are scarce, and available only for the populations of south-central Italy. In this note we report preliminary data about the diet of an Apennine population of the three-toed skink, Chalcides chalcides, at the northern boundary of its distribution area. Faecal contents from 20 individuals were collected in June 2015, obtaining an overall sample of 48 prey items. Araneae constituted the most preyed taxon (over 40%), followed by Hemiptera (35,4%) and other prey taxa (Hymenoptera, Coleoptera, and Dermaptera) in much lower percentages. We found no differences between smaller/younger and larger/older individuals in consumed preys. As well as confirming the general trophic predilection of this skink for spiders, we also found some interesting differences in preyed items with studied populations of south-central Italy
Bergman’s rule and the Italian Hermann’s Tortoises (Testudo hermanni): latitudinal variations of size and shape
No full textWe used geometric morphometric analysis to investigate latitudinal variation in size and shape of carapace and plastron of I I I Testudo hermanni hermanni (60 males and 51 females) collected in 6 different Italian regions. Basing on a sample of 14 landmarks for carapace and 18 landmarks for plastron, we showed that the size and shape of both sexes changed according to a North-South cline following the Bergmann's rule, tortoises of Northern Italy being 1.1-1.2 larger than that of Southern Italy. Shape variation was higher in carapace probably because sexual selection in this species acts stronger on plastron than on carapace shape
Dorsal pattern polymorphism in female Iberian wall lizards: Differences in morphology, dorsal coloration, immune response, and reproductive investment
No full textSex-specific colour polymorphisms have been extensively documented in many different taxa. When polymorphism in colour pattern is restricted to females, the condition is known as female-limited pattern polymorphism (FPP), which has been less commonly addressed in vertebrates. FPP is present in several lizard species, although most research on lizards has focused on carotenoid- and pteridine-based coloration and not on melanin-based polymorphisms. In the present study, we focus on Iberian wall lizards, Podarcis hispanicus, where two female melanin-based dorsal patterns can be clearly distinguished: striped and reticulated-blotched. We indirectly tested the hypothesis that selection acts differentially among P. hispanicus female morphs to create alternative morph-specific phenotypic optima at different levels by investigating whether morphs differ in fitness proxies. We specifically examined whether the two female dorsal pattern morphs differed in adult morphology, dorsal coloration, immune response, reproductive investment, and growth. We did not find a relationship between melanin-based coloration and hatchling growth and immune response, despite a correlation between these traits possibly being expected as a result of pleiotropy in the melanocortin system. However, our results show that female dorsal morphs in P. hispanicus differ in terms of adult morphology, dorsal coloration, and reproductive investment. Reticulated-blotched P. hispanicus females had deeper heads and longer femora, less melanin, and more brownish coloration, and also had larger and heavier hatchlings than striped females
Female preference for fast-rate, high-pitched calls in Hermann’s tortoises Testudo hermanni
No full textThe courtship and mounting behavior of promiscuous tortoises is based on a multiple signaling system that includes visual,
olfactory, tactile, and acoustic signals. Vocalizations related to mounting seem to be particularly intriguing because tortoises
vocalize mainly at this time. Vocalizations and courtship behavior might be costly for males, and if these costs increase
differentially for different males, then the potential exists for vocalizations and displays to reveal male individual quality on which females could base their mate choice. In the present study, by using individuals breeding in seminatural enclosures, we experimentally investigated whether the mounting call of male Hermann’s tortoises (Testudo hermanni) represents a relevant stimulus to both males and females. We also looked for potential preference toward different acoustic stimuli in order to determine which call features, if any, played a role in attracting potential partners or deterring rivals. Females were sensitive to call playback, whereas males apparently paid little attention to playback. In addition, females showed a significant preference toward high-pitched calls emitted at high rate. Also, females exhibited a strong tendency toward short-duration calls. Because call rate is related to hematocrit in Hermann’s tortoise males, by responding to fast-rate calls females are also choosing high-quality partners as sires of their offspring. This is the first study in which an attractive function of tortoise vocalizations has been documented
Effects of predation risk on the sensory asymmetries and defensive strategies of Bufotes balearicus tadpoles
No full textLateralization consists of the differential use of bilateral organs or limbs and is well described in many taxa and in several contexts. Common ecological frameworks where it can be observed are foraging and predatory ones, with benefits related to both visual and auditory lateralization such as faster response or increasing neural processing ability. Anuran amphibians are considered relevant models for investigating lateralization, due to their great ecological variety and the possibility of easily being raised under laboratory conditions. By adopting the "rotational preference test", we used Balearic green toad tadpoles to test the effects of behavioural defensive responses triggered by different predator types (native vs alien, i.e. dragonfly larvae Aeshna cyanea and adult red swamp crayfish Procambarus clarkii) and diets (fasted vs. tadpole-fed predators) on their lateralization. We recorded tadpoles' responses to five different chemical cues: clean water (control treatment), fasted dragonfly larvae and crayfish, and tadpole-fed dragonfly larvae and crayfish. Green toad tadpoles did not show a bias in a predominant direction, although lateralization occurred at the individual level, as shown by the intensity index (LA). Perceived predation risk was the highest in tadpoles exposed to the combined chemical cues of conspecific prey and native predators, which elicited both changes in the intensity of lateralization and a marked reduction in tadpoles' activity level. Our results suggest that contextual predation threat may induce very rapid changes in the expression of asymmetries at the individual level, and might play a role as part of the complex defensive strategies adopted by prey in the attempt to escape predators
Olfactory discrimination of species, sex, and sexual maturity by the Hermann’s tortoise Testudo hermanni
Full text linkMany animals obtain reliable information about potential mates, including whether they are conspecific, sexually mature, and healthy or not, mostly from olfactory cues. Previous experiments with snakes and lizards have shown that individuals can recognize conspecifics, sex, mating status, and health condition of potential partners by chemical cues. Using choice experiments, we examined whether both male and female Hermann's Tortoises, Testudo hermanni, can detect and distinguish the odor of conspecifics from that of another species and an odorless control, and are able to discriminate sex and sexual maturity of individuals by chemical cues. We found that both sexes correctly discriminated between their own species and another species' odors, but only males can distinguish sex and sexual maturity of potential mates by olfactory cues. These results indicate a sexual dimorphism in olfactory sensitivity in this species that might be derived from sexual selection and suggest that males and females should rely on different communication channels during social interactions
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