A team of zoologists from Germany and Czech Republic has discovered a new species of chameleon living on the slopes of the Bale Mountains in Ethiopia.
Living individual of Trioceros wolfgangboehmei from Dinsho, Ethiopia showing a prominent white temporal spot and dorsolateral longitudinal stripe. Image credit: Petr Nečas.
Chameleons are one of the most fascinating groups of squamate reptiles, not only due to their exceptional behavior or adaptations, but also because of their extraordinary species diversity and distribution.
The more than 215 described species of the family Chamaeleonidae are distributed from Africa, Southern Europe and the Middle East to parts of South Asia. Apart from the fact that Madagascar is a well-known hotspot of chameleon diversity, it was hypothesized that this family originated in mainland Africa.
The African continent harbors not only a broad variety of distinct chameleon species, but, in particular, also a high number of endemics that are restricted to single mountains or mountain ranges.
Examples include the genus Kinyongia, but also several species of the genus Trioceros, to which the newly-discovered species belongs.
“The Bale Mountains in south-central Ethiopia are considered to be one of the most unique centers of endemism, with an extraordinary number of plants and animals that can only be found there,” said lead author Thore Koppetsch from the Alexander Koenig Research Museum and his colleagues.
“There were already two species of the chameleon genus Trioceros known to be restricted to the Bale region when we discovered another unique representative of this group from the northern slopes of the Bale Mountains.”
“Interestingly, this new chameleon is considered to be part of a species complex of the wide-spread Ethiopian chameleon (Trioceros affinis).”
“Previous studies have indicated divergence between its different populations across the Ethiopian Highlands — with some of them separated by the northern extension of the Great Rift Valley, which also shaped the evolution of early humans.”
Named Trioceros wolfgangboehmei, the new species is a small-sized chameleon with a total length of 15.6 cm (snout-vent length of 6.5 cm and a tail length of 9.1 cm); the head is relatively short, 1.9 cm long.
The ground body color of living individuals is yellowish, brownish or even bright green and varies in different individuals.
“The new species has a characteristic appearance, displaying enlarged spiny scales on its back and tail that form a prominent crest,” the researchers said.
“It usually lives on small trees and bushes at an altitude of above 2,500 m above sea level.”
Trioceros wolfgangboehmei prefers to live on small trees and bushes. Juveniles can be found in grass, but always adjacent to trees and bushes.
The species is only known from a small region around two villages, Dinsho and Goba, in the Bale Mountains in south-central Ethiopia.
It appears to be restricted to this area and can be considered as another endemic for these mountains.
“A part of the population is well protected within the Bale Mountains National Park,” the authors said.
“But another part is living outside, in the agriculturally used areas and even in gardens and remnants of vegetation in the local villages.”
The discovery of Trioceros wolfgangboehmei is described in a paper in the journal Zoosystematics and Evolution.
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T. Koppetsch et al. 2021. A new chameleon of the Trioceros affinis species complex (Squamata, Chamaeleonidae) from Ethiopia. Zoosystematics and Evolution 97 (1): 161-179; doi: 10.3897/zse.97.57297
