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In: Contributions to Zoology
In: Contributions to Zoology
Author: Miguel Vences

Abstract

Evidence is presented that golden-striped salamander Chioglossa lusitanica populations in eucalypt plantations may be subject to two influences. There is a low density of leaf litter invertebrates which are the preferred prey. Substrate choice experiments show that that the salamanders avoid eucalypt leaves as substrates for shelter. A long-term study of Chioglossa populations at two brooks in northern Portugal, however, showed that the numbers at one site did not change notably after plantation with eucalypts in comparison with the other, less altered, locality. Chioglossa is the most abundant amphibian species along water courses in the Spanish province of La Coruña, although eucalypts are planted along most of them.

In: Amphibia-Reptilia
Authors: Miguel Vences and Frank Glaw

Abstract

We describe a new frog species of the Mantidactylus boulengeri group (Amphibia: Anura: Mantellidae) in the subgenus Gephyromantis from south-eastern Madagascar. It is morphologically similar to M. eiselti and M. thelenae but differs in its advertisement calls with a distinctly shorter note duration, and in its bilobate (not single) subgular vocal sac. Like M. eiselti and M. thelenae the new species Mantidactylus enki is predominantly diurnal and calling males do not aggregate close to water bodies, indicating direct development as it has been demonstrated previously in M. eiselti. The advertisement calls of all three species are described in detail. A comparison with a further pair of cryptic species with bilobate vs. single subgular vocal sac (Mantidactylus tschenki — M. cornutus) did not reveal any consistent pattern of call variation correlated with vocal sac structure. Therefore, sexual selection may also be considered to explain differences in the colour and external structure of vocal sacs among closely related species.

In: Amphibia-Reptilia
Authors: Frank Glaw and Miguel Vences

Abstract

Advertisement calls of the Discoglossus-species D. pictus, D. sardus, D. galganoi, and D. montalentii were studied. In comparison with all other species, the advertisement call of D. montalentii is completely different. The frequency spectrum displays a harmonic structure and resembles a Bombina-call, while advertisement calls of the other Discoglossus species are mostly unharmonious. D. pictus auritus and D. pictus pictus show a great similarity of call patterns. D. galganoi is characterized by the longest call duration. The call of a red-backed Discoglossus with the vague locality "Sardinia", here named "D. spec.", differed substantially from the calls of D. sardus and any other studied specimen. The complex situation regarding the distribution of different Tyrrhenian Discoglossus phenotypes is discussed in this context.

In: Amphibia-Reptilia
Authors: Miguel Vences and Frank Glaw

Abstract

Advertisement calls of Discoglossus galganoi jeanneae from two localities in southern Spain and D. pictus scovazzi from Ceuta were analyzed. Call duration as well as ratio of pulse group intensities and durations clearly group D. pictus scovazzi with the other subspecies of D. pictus (pictus and auritus). The calls of the taxon jeanneae show some differences to calls of populations of D. g. galganoi from northern Spain, but are more similar to calls of D. g. galganoi than to those of D. pictus scovazzi. These data support the status of jeanneae as subspecies of galganoi.

In: Amphibia-Reptilia

Abstract

The treefrog genus Boophis is represented in Madagascar by 50 described species. In this paper we describe two new cryptic species: B. liami sp. nov. and B. solomaso sp. nov. are similar to B. mandraka in morphology and colouration, but are clearly different in bioacoustic and genetic characters. The existence of many sibling species within Boophis shows the importance of detailed studies to clarify the distribution and the ecological requirements of the species in this genus. Les anoures arboricoles du genre Boophis sont représentés à Madagascar par 50 espèces. Dans cet article nous décrivons deux nouvelles espèces cryptiques : B. liami sp. nov. et B. solomaso sp. nov. ressemblent a B. mandraka par la coloration et la morphologie, mais ce distinguent clairement par la bioacoustique et le caractères génétiques. L'existence de beaucoup de "sibling species" dans le genre Boophis montre l'importance des études détailles pour qu'on puisse clarifier les questions concernant la répartition et les demandes écologiques des espèces de ce genre.

In: Amphibia-Reptilia

Abstract

Age structure of populations of four species of endemic Malagasy frogs of the genus Mantella (M. aurantiaca, M. baroni, M. bernhardi, M. madagascariensis) was examined by skeletochronology based on 96 specimens from nine different localities. In more than half of these (57%), no lines of arrested growth (LAGs) were found, and the number of LAGs recognized in the remaining specimens was mostly one, and probably two in three specimens. It is generally considered that each LAG corresponds to one year of life; our results therefore confirm that in Mantella populations almost all specimens are in their first or second year of life.

In: Amphibia-Reptilia