0000000000132279
AUTHOR
Stefan Lötters
showing 12 related works from this author
Phylogeography of Ptychadena mascareniensis suggests transoceanic dispersal in a widespread African-Malagasy frog lineage
2004
Aim The Mascarene ridged frog, Ptychadena mascareniensis, is the only African amphibian species thought to occur on Madagascar and on the Seychelles and also Mascarene islands. We explored its phylogenetic relationships and intraspecific genetic differentiation to contribute to the understanding of transoceanic dispersal in amphibians. Methods Fragments of the mitochondrial 16S rRNA gene were sequenced from specimens collected over most of the distribution area of P. mascareniensis, including populations from Madagascar, Mascarenes and Seychelles. Results We identified five deeply divergent clades having pairwise divergences >5%, which probably all represent cryptic species in a P. mascaren…
Disentangling composite colour patterns in a poison frog species
2008
A phylogenetic approach was performed to infer whether variation in conspicuous colour-patterns of a poison frog (Dendrobatidae: Dendrobates tinctorius) has evolved neutrally or under selection. Colour and pattern were split into components that were separately analysed and subsequently re-grouped via principal component analysis. This revealed four different ‘displayed’ factors on the dorsal and lateral views versus one ‘concealed’ factor on the ventral view. Based on the assumption that current patterns of trait variation contain information about the evolutionary history of the phenotype, we correlated these trait components to a neutrally evolving gene fragment (cytochrome b). The conce…
Convergent evolution of aposematic coloration in Neotropical poison frogs: a molecular phylogenetic perspective
2003
Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2014-02-26T17:17:10Z No. of bitstreams: 1 WOS000186417800006.pdf: 196897 bytes, checksum: cbe901a47807d22aec173ee8cc011a64 (MD5) Made available in DSpace on 2014-02-26T17:17:10Z (GMT). No. of bitstreams: 1 WOS000186417800006.pdf: 196897 bytes, checksum: cbe901a47807d22aec173ee8cc011a64 (MD5) Previous issue date: 2003-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:59:12Z No. of bitstreams: 1 WOS000186417800006.pdf: 196897 bytes, checksum: cbe901a47807d22aec173ee8cc011a64 (MD5) Made available in DSpace on 2014-05-20T13:59:12Z (GMT). No. of bitstreams: 1 WOS000186417800006.pdf: 196…
Conservation priorities for harlequin frogs (Atelopus spp.) of Peru
2005
Populations of harlequin frogs Atelopus are declining throughout their geographical range. In Peru six of the 11 nominally described species are Critically Endangered, and there are at least 17 undescribed additional forms (all representing apparently distinct species), the conservation status of which is unknown. Most Atelopus taxa in Peru have relatively small geographical ranges, some known only from single populations, and have only a limited chance of survival. Conservation will require: (1) improvement of the faunistic and taxonomic knowledge of the genus, (2) field surveys, including in remote areas, (3) assessment of all species and populations for chytridiomycosis and research on t…
Phylogeny and classification of poison frogs (Amphibia: dendrobatidae), based on mitochondrial 16S and 12S ribosomal RNA gene sequences.
2000
An analysis of partial sequences of the 16S ribosomal rRNA gene (582 bp) of 20 poison frog species (Dendrobatidae) confirmed their phylogenetic relationships to bufonid and leptodactylid frogs. Representatives of the ranoid families and subfamilies Raninae, Mantellinae, Petropedetinae, Cacosterninae, Arthroleptidae, Astylosternidae, and Microhylidae did not cluster as sister group of the Dendrobatidae. Similar results were obtained in an analysis using a partial sequence of the 12S gene (350 bp) in a reduced set of taxa and in a combined analysis. Within the Dendrobatidae, our data supported monophyly of the genus Phyllobates but indicated paraphyly of Epipedobates and Colostethus. Minyobat…
Another New Riparian Dendrobatid Frog Species from the Upper Amazon Basin of Peru
2003
A new dendrobatid frog of the genus Colostethus is described from the Cordillera El Sira, an isolated mountain ridge in the upper Amazon basin of central Peru. It has bright yellowish dorsolateral stripes thus resembling Colostethus exasperatus, Colostethus sp. (cf. exasperatus), and Colostethus nexipus, all from the upper Amazon basin of Ecuador and Peru. In morphology, the new species is most similar to Colostethus mcdiarmidi from the eastern Andean slopes of Bolivia and Colostethus alessandroi from the eastern Andean slopes of Peru. The new species can be distinguished from all these taxa on the basis of coloration including the color of the ring around pupil in life, adult male size, le…
Distribution patterns of amphibians from the Kakamega forest, Kenya
2005
We discuss generalized geographical range patterns for the 24 anuran species that occur in the Kakamega Forest, western Kenya. Eight distributions are distinguished: from "western Equatorial Rift Valley" to almost entire sub-Saharan. The former may be more common than previously assumed, because some species displaying this geographical range pattern were only recently identified out of species complexes with large distributions. In contrast, continuous distributions of species over the Congo basin may be less common than currently understood.
Tadpole of Atelopus franciscus from French Guyana, with Comments on Other Larvae of the Genus (Anura: Bufonidae)
2005
The tadpole of Atelopus franciscus from French Guyana is described. It resembles other larvae of the genus, especially those displaying a color pattern of symmetrical light marks. Among them, A. franciscus is most similar to those tadpoles having submarginal papillae (i.e., Atelopus balios, Atelopus flavescens, Atelopus nanay, Atelopus tricolor). The tadpole of A. franciscus shares several similarities with the larva of A. flavescens from French Guyana but differs from it by being smaller in size and in certain measurement. The phylogenetic relevance of tadpole characters in Atelopus is discussed, including body proportions, submarginal papillae, length of upper beak.
The stream-dwelling tadpole ofHyloscirtus charazani(Anura: Hylidae) from Andean Bolivia
2005
Abstract We describe the lotic larva of Hyloscirtus charazani from Charazani and nearby areas, Departamento La Paz, Bolivia (2700–3200 m a.s.l.). It is morphologically undistinguishable from tadpoles of H. armatus sensu lato. These tadpoles show stream adaptation through a robust body with strong tail musculature, enlarged oral disc, increased number of labial tooth rows, and complete marginal papillae. Furthermore, they have a large saccular structure that underlies the limb buds, encloses the vent tube, and partially covers the hindlimbs during their development. Resumen Describimos la larva lotica de Hyloscirtus charazani de Charazani y de otra localidad cercana, Departamento La Paz, Bol…
The stream-dwelling larva of the Ruwenzori River Frog, Amietia ruwenzorica, its buccal cavity and pathology of chytridiomycosis
2012
Tadpoles of Amietia ruwenzorica (Pyxicephalidae, Cacosterninae) were collected in the Ruwenzori Mountains, Uganda(identified by DNA barcoding). The ventrally directed enlarged oral disc with a high number of labial tooth rows (LTRF9(4)/9(1)) and the narrow tail with robust caudal musculature characterise them as stream-dwellers. We name this mor-photype the 'common or standard type of stream-adaptation', because special additional adhesive organs are missing in A.ruwenzorica. The uniserially arranged oral teeth of the spoon-shaped type with 16 to 18 cusps per tooth are known fromother anuran larvae, especially from pyxicephalids. The buccal morphology resembles generalized tadpoles with som…
Catastrophic Population Declines and Extinctions in Neotropical Harlequin Frogs (Bufonidae: Atelopus)1
2005
We surveyed the population status of the Neotropical toad genus Atelopus, and document recent catastrophic declines that are more severe than previously reported for any amphibian genus. Of 113 species that have been described or are candidates for description, data indicate that in 42 species, population sizes have been reduced by at least half and only ten species have stable populations. The status of the remaining taxa is unknown. At least 30 species have been missing from all known localities for at least 8 yr and are feared extinct. Most of these species were last seen between 1984 and 1996. All species restricted to elevations of above 1000 m have declined and 75 percent have disappe…
Sole coloration as an unusual aposematic signal in a Neotropical toad
2019
Many animals have evolved remarkable strategies to avoid predation. In diurnal, toxic harlequin toads (Atelopus) from the Amazon basin, we find a unique colour signal. Some Atelopus populations have striking red soles of the hands and feet, visible only when walking. When stationary, the toads are hard to detect despite their yellow-black dorsal coloration. Consequently, they switch between high and low conspicuousness. Interestingly, some populations lack the extra colour display of the soles. We found comprehensive support that the red coloration can act as an aposematic signal directed towards potential predators: red soles are significantly more conspicuous than soles lacking red colora…