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  • Author or Editor: Antonio Romano x
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Sex ratio is an essential demographic parameter and distortions from a balanced sex ratio may have contrasting effects on the population dynamics. However, observation of distorted sex ratio using counts or captures may reflect an actual ecological trait of the studied population but may also be an artefact due to different capture probabilities of males and females. We compared results obtained from Counts and Capture-Marking-Recapture (CMR) on both sexes in a population of a forest dwelling salamander, Salamandrina perspicillata, and we investigated if males and females had different capture probabilities. We surveyed available literature to compare information on sex ratio from other populations of S. perspicillata. The sex ratio from our counts was 0.65 and was significantly male-biased as reported in other studies. The estimated sex ratio from CMR data was 0.57. Although males showed higher recapture rates than females in every capture session, these differences were not statistically significant. Therefore, the skewed sex ratio towards males is not only an artefact due to different capture probabilities between males and females but reflects an actual demographic trait, although the magnitude of the skeweness was overestimated by counts.

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In: Amphibia-Reptilia

Abstract

The knowledge of reproductive behaviour of Salamandrina perspicillata, an endemic Italian salamander, is still fragmented and not exhaustive; and the only detailed observations were made just once in a terrarium. We describe many aspects of the terrestrial courtship behaviour such as male alert posture, substrate marking trail, approach and pursuit, tail undulation and vent swinging, and spermatophore deposition and pick-up. The courting pair follows an ellipsoidal track during this manoeuvre a spermatophore is deposited by the male just in front of the female who will reach the spermatophore as she continues to circle. No body contacts were observed during the courtship. Tail movements play a key role in the communication between sexes as well as between antagonistic males. Male-male combat involves biting as the main deterrent. We found that the mating season in wild populations is in the spring, differing from that reported previously for mating in captivity (winter) or extrapolated from the beginning of sperm storage (autumn). Each of these points is discussed in light of available information on social communication, sexual dimorphism, courtship evolution, and sperm storage.

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In: Amphibia-Reptilia

Abstract

Salamandrina perspicillata is an endemic Italian salamander in which morphological sexual dimorphism is weak and sexes are almost indistinguishable in live specimens. We here report on a simple method for sexing these salamanders in the field on the basis of cloacal morphology and we present new data on the sexual dimorphism in this species. Nine morphological characters were used to assess the amount of sexual dimorphism using a multivariate approach (Mancova: Wilks' λ = 0.248, P < 0.001). Sexes differed significantly in both size (females are larger than males) and shape (females have proportionally longer distance between extremities, males have longer cloacal slit and wider head). The observed pattern of sexual dimorphism is discussed in an evolutionary context. Difference between sexes in the proportion of the V-shaped patch on the head was also tested. Finally, we also report the first preliminary data on the sex ratio of a S. perspicillata population in the wild.

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In: Amphibia-Reptilia

Abstract

This chapter collects the texts that the medieval European authors wrote in Latin about the religion of the Slavs: these authors, fundamentally chroniclers, are the main source to know the religion of the Slavs of Central Europe and the Slavs of the Baltic. Also we find ecclesiastical instructions on popular religiosity in Poland during the fourteenth and fifteenth centuries where we trace information on the Slavic Pre-Christian religion.

In: Sources of Slavic Pre-Christian Religion

Abstract

To improve monitoring techniques, we investigated the colour vision of the Calabrian Alpine newt (Ichthyosaura alpestris inexpectata). We conducted controlled behavioural experiments on male and female newts to explore their response to artificial coloured light sources in the dark. We used green, blue, and orange glow sticks. Observations indicated that both sexes strongly preferred green glow sticks, which were selected in almost 50% of the trials Additionally, newts exhibited markedly swifter reactions to green light. The attraction to green glow sticks may be due to the biofluorescence within the green wavelength spectrum in this newt. This glowing ability, which resembles the green glow stick’s glow, could be beneficial in low-light conditions to locate other newts. Our results show that the behavioural preferences towards a particular light source can significantly enhance the success of capturing newts during population monitoring and conservation efforts for this rare and threatened taxon.

In: Amphibia-Reptilia

The study of trophic ecology of terrestrial salamanders is central for a better understanding of their adaptability and dispersal, in particular in Mediterranean ecosystems where their feeding activity is reduced because of prolonged arid periods. Terrestrial salamanders are generalist predators that feed on a large array of invertebrate prey groups, however, there are few studies comparing the feeding strategy and the trophic specialization at the individual level in conspecific populations of salamanders living in different habitats. In this study, two populations of the Sardinian endemic salamander Speleomantes imperialis were sampled in areas characterized by different climate, vegetation and geological substrate. Dietary habits, obtained by stomach flushing, and physiological condition, assessed through a body condition index, were analysed and compared between populations. The two populations displayed different diets on the basis of the taxonomic composition of prey categories, but both of them behaved as generalist predators and shared a similar body condition index. Moreover, in both populations the indices of individual trophic specialization were significantly different from null models assuming a random prey distribution among predators. Therefore, the two populations were largely composed by individually specialized salamanders. Overall, these findings are in good agreement with other studies on the trophic ecology of top predators and in particular of terrestrial salamanders. The realized trophic strategies, i.e. generalist at the population and specialist at the individual level, were highly consistent geographically and the two populations exploited the different arrays of prey found in their environments similarly.

In: Animal Biology

To date the most commonly used non-lethal methods in amphibian dietary studies are stomach flushing and faecal analysis. In this study, we compared the outcome of these two methods in interpreting prey selectivity when the available prey community in the environment is known. Stomach flushed contents and faeces were obtained from the same 27 individuals of the spectacled salamander (Salamandrina perspicillata) from a site in Central Italy. The interpretation of the population prey selection strategy varied in relation to the method used. Stomach content analysis suggested that salamanders were highly specialized on springtails, while faecal contents indicated a generalist trophic strategy. Prey selectivity indexes were also highly divergent: the analysis of stomach contents indicated a significant positive selection upon springtails, while exactly the opposite conclusion was obtained when faecal contents were analyzed. The results confirm that in amphibians, stomach analysis provides more reliable dietary data in comparison to faecal analysis. This is related to the fact that soft-bodied prey items tend to be more fully digested, disappearing in faeces while highly chitinized and less digestible prey taxa tend to increase their relative abundances in faeces.

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In: Amphibia-Reptilia