DOI: 10.3897/zse.101.151926

Authors: Krystal A. Tolley, Devon C. Main, Keith M. Dube, Bettine Jansen van Vuuren, Jessica M. da Silva

Abstract: Differing ecological conditions are considered drivers of directional selection among or between populations, resulting in ecological speciation. In particular, divergence of phenotypes in differing habitats, or convergence of phenotypes in similar habitats, can be the result of directional selection. Accordingly, species of dwarf chameleons (Bradypodion) that occur in structurally similar habitats tend to converge on a similar phenotype. Conversely, dwarf chameleons from contrasting habitats have been shown to diverge in phenotype. Thus, ecological speciation appears to be a mechanism for diversification in this genus. Using a combination of morphological (functional and ornamental traits) and population genetic analyses (microsatellite loci), we examined whether three closely related Bradypodion lineages have diverged for these dimensions. We assess whether habitats differ in structure for features related to divergence in morphological traits or whether convergence of traits corresponds to similarity in habitat structure. We find that the three taxa differ significantly at a population genetic level, but some allele sharing suggests incomplete lineage sorting or gene flow. Differences among taxa for functional traits related to gripping of branches (e.g., distal limb size [hands/feet]) can be explained by the perch diameters used by chameleons, whereas the degree of ornamentation differs among taxa in different habitats but is convergent for those in similar habitats. These outcomes are congruent with an ecological model of speciation, with taxa having diverged genetically but showing phenotypic convergence when in similar habitats and divergence when in different habitats.

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DOI: 10.3897/zse.97.57297

Authors: Thore Koppetsch, Petr Nečas, Benjamin Wipfler

Abstract: A new species of chameleon, Trioceros wolfgangboehmei sp. nov., inhabiting the northern slopes of the Bale Mountains in Ethiopia, is described. It differs from its Ethiopian congeners by a combination of the following features: presence of a prominent dorsal crest with a low number of enlarged conical scales reaching along the anterior half of the tail as a prominent tail crest, a casque raised above the dorsal crest, heterogeneous body scalation, long canthus parietalis, rugose head scalation, high number of flank scales at midbody and unique hemipenial morphology. Based on morphological characteristics, phylogenetic discordances of previous studies and biogeographical patterns, this new species is assigned to the Trioceros affinis (Rüppell, 1845) species complex. An updated comprehensive key to the Trioceros found in Ethiopia is provided.

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DOI: 10.3897/zse.95.32818

Authors: Mark D. Scherz, Jörn Köhler, Andolalao Rakotoarison, Frank Glaw, Miguel Vences

Abstract: We describe a new species of dwarf chameleon from the Brookesia minima species group. Brookesia tedi sp. n. occurs above 1300 m above sea level on the Marojejy massif in northeastern Madagascar. It is genetically sister to B. peyrierasi, a species occurring in lowlands around the Baie de Antongil, but is genetically strongly divergent from that species in both nuclear (c-mos) and mitochondrial (16S, ND2) genes, and morphologically in its smaller size and distinctly different hemipenis. It is the second species of the B. minima species group from Marojejy National Park, but is not known to occur in syntopy with the other species, B. karchei, due to elevational segregation.

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DOI: 10.3897/zse.94.27305

Authors: David Prötzel, Shea M. Lambert, Ginah Tsiorisoa Andrianasolo, Carl R. Hutter, Kerry A. Cobb, Mark D. Scherz, Frank Glaw

Abstract: On a recent expedition to eastern Madagascar, we discovered a distinct new species of the genus Calumma that we describe here using an integrative approach combining morphology, coloration, osteology and molecular genetics. Calumma roaloko sp. n. has a dermal rostral appendage and occipital lobes, and belongs to the C. boettgeri complex, within the Madagascar-endemic phenetic C. nasutum species group. It is readily distinguished from other species of the C. boettgeri complex by a characteristic two-toned body coloration and small body size with a snout-vent length of 45.6 mm in an adult male. The osteology of the skull, with a prominent maxilla and broad parietal, is similar to the closest related species, C. uetzi. Analysis of uncorrected genetic distances within the C. nasutum group using the mitochondrial gene ND2 shows a minimum pairwise distance of 11.98% to C. uetzi from the Sorata massif and Marojejy National Park >500 km north of the type locality of C. roaloko sp. n.. Given an apparently small range (potentially <300 km2), located entirely outside of any nationally-protected areas, we recommend this new species be classified as Endangered under criterion B1ab(iii) of the IUCN Red List. The discovery of clearly distinct species like C. roaloko sp. n. in an area of Madagascar that is comparatively thoroughly surveyed highlights the critical role of continued field surveys for understanding the true extent of Madagascar’s spectacular biodiversity.

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DOI: 10.3897/zse.92.6464

Authors: David Prötzel, Bernhard Ruthensteiner, Frank Glaw

Abstract: Calumma vatosoa is a Malagasy chameleon species that has until now been known only from the male holotype and a photograph of an additional male specimen. In this paper we describe females of the chameleon Calumma vatosoa for the first time, as well as the skull osteology of this species. The analysed females were collected many years before the description of C. vatosoa, and were originally described as female C. linotum. According to external morphology, osteology, and distribution these specimens are assigned to C. vatosoa. Furthermore we discuss the species group assignment of C. vatosoa and transfer it from the C. furcifer group to the C. nasutum group. A comparison of the external morphology of species of both groups revealed that C. vatosoa has a relatively shorter distance from the anterior margin of the orbit to the snout tip, more heterogeneous scalation at the lower arm, a significantly lower number of supralabial and infralabial scales, and a relatively longer tail than the members of the C. furcifer group. These characters are, however, in line with the species of the C. nasutum group. In addition the systematic position of C. peyrierasi also discussed, based on its morphology.

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