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| Furcifer voeltzkowi (Boettger, 1893) in Glaw, Prötzel, Eckhardt, ... et Vences, 2020. |
Abstract
The chameleon Furcifer voeltzkowi (Boettger, 1893) from northwestern Madagascar was considered to be a synonym of Furcifer rhinoceratus for many decades and was resurrected only recently based on studies of the morphology and osteology of a few male specimens, which were collected more than 100 years ago. However, basic data on this species remain unavailable, including its conservation status, life history, colouration in life, morphology of the female, genital morphology of the male, phylogenetic affinities, and genetic differentiation from F. labordi and other congeners. During a targeted expedition, we rediscovered F. voeltzkowi in its natural habitat close to its type locality, allowing us to fill some gaps of knowledge. Furcifer voeltzkowi is a sexually dimorphic species. The life colouration of males is largely green, whereas that of females is highly variable and can be extremely colourful. Both, morphology and life colouration of males and females show close similarities to F. labordi from west and southwest Madagascar, but also a number of distinct differences (e.g. a larger size of F. voeltzkowi and a smaller rostral appendage in both sexes), enabling a clear distinction of the two species in both sexes. DNA sequences of the nuclear CMOS gene and two mitochondrial markers (16S rRNA and ND4) also confirm that F. voeltzkowi is a distinct species and sister to F. labordi (pairwise differences in the 16S gene 3.5–3.6%). We estimate the distribution range (extent of occurrence) of F. voeltzkowi to comprise ca. 1.000 km2 and suggest that it qualifies as Endangered B1ab(iii) under the IUCN Red List Criteria as its populations are expected to be severely fragmented, and there is continuing decline in the extent and quality of its habitat. Similar to F. labordi, F. voeltzkowi might be an extremely short-living chameleon with a post hatching life span of only several months in the rainy season. The assumed short life might also partly explain why this splendid species got “lost” for many decades, since most roads in its habitat are not accessible in the wet season.
Key words. Squamata, Chamaeleonidae, morphology, molecular genetics, rediscovery, conservation.
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| Figure 2. Males of Furcifer voeltzkowi from Katsepy near Mahajanga in different colour states: A) slightly stressed; B, C) relaxed (subadult); D, E) displaying. Note in (A) the injuries on the head probably resulting from intraspecific conflicts. Males differ from those of the sister species F. labordi by larger size, a lower casque, a shorter rostral appendage, darker skin around the scales and a row of white and distinctly enlarged tubercles along the flanks. |
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| Figure 3. Females of Furcifer voeltzkowi from Katsepy near Mahajanga in different colour states: A) stressed/gravidity colouration; B, C) rather relaxed; D, E) stressed. The females differ from those of the sister species F. labordi by larger size, often by a rudimentary, poorly recognizable rostral appendage, and several details of their colouration (e.g. 2–3 red dorsolateral spots versus only one in F. labordi). |
Furcifer voeltzkowi (Boettger, 1893)
Frank Glaw, David Prötzel, Falk Eckhardt, Njaratiana A. Raharinoro, Rojo N. Ravelojaona, Timon Glaw, Kathrin Glaw, Julia Forster and Miguel Vences. 2020. Rediscovery, Conservation Status and Genetic Relationships of the Malagasy Chameleon Furcifer voeltzkowi. SALAMANDRA. 56(4); 342–354. salamandra-journal.com/index.php/home/contents/2020-vol-56/1996-glaw-f-d-proetzel-f-eckhardt-n-a-raharinoro-r-n-ravelojaona-t-glaw-k-glaw-j-forster-m-vences/file
