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| Holaspis ngalangi Parrinha, Marques, Gonçalves, Tiutenko, Bauer & Ceríaco, 2025 Drawing by Arthur Tiutenko. |
Abstract
The members of the Afrotropical lacertid genus Holaspis are strikingly specialized lizards, adapted for gliding in forest canopies, with serrated blue tails. Two species are currently recognized within the genus: Holaspis guentheri from West and Central Africa, and Holaspis laevis from East Africa. The currently known southern limits of H. guentheri are in the northern Angolan Guineo-Congolian habitats, which are remnants of forests connecting the country to West/Central Africa. The oldest record of the species in Angola, dating back to the 19th century, is based on a currently lost specimen collected by José d’Anchieta near Caconda, southwest Angola. Caconda is situated on the Angolan Central Plateau, which is part of the Great Escarpment of southern Africa. The loss of Anchieta’s specimen and its geographic context led most authors to disregard it, leaving its taxonomic identity dubious until now. The rediscovery of two additional specimens from Caconda, collected by William John Ansorge in the early 20th century and deposited in the Natural History Museum, London, allowed us to confirm the presence of the genus in the region, prompting targeted surveys and examination of additional material. Our surveys failed to locate any Holaspis near Caconda, with alarming rates of deforestation in the region raising the possibility that this population may already be extinct. The reexamination of the extant Caconda specimens and comparison with H. guentheri and H. laevis revealed consistent morphological differences that suggests that the Caconda population may represent a distinct taxonomic unit. Here we describe the Holaspis from Caconda as a new species, presumably endemic to the Angolan Central Plateau. These findings and their implications are discussed in the biogeographical context of the highlands of western Angola, a recognized hotspot of diversity and endemism for several taxonomic groups.
Key words. Taxonomy, biogeography, natural history collections, deforestation, highlands.
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| Illustration of Holaspis ngalangi sp. n. in its putative
habitat, with threats such as deforestation represented in the
background. Drawing by Arthur Tiutenko. |
Holaspis ngalangi sp. n.
Defnition: Holaspis ngalangi sp. n. is defned by the following combination of characters: 1) Head, body and tail
strongly depressed, with serrated fringes on hindlimbs and
tail; 2) frontoparietals fused with interparietal; 3) two series of transversely enlarged vertebral plates along dorsum
and tail; 4) dorsum black with three pairs of pale stripes,
with paravertebral stripes confned to enlarged dorsal
plates; 5) an uninterrupted series of paired, transversely
enlarged scales between ventral and precloacal scales (see
Fig. 7).
Diagnosis: Holaspis ngalangi sp. n. can be readily distinguished from both of its congeners, H. guentheri and
H. laevis, by the presence of an uninterrupted series of
paired, transversely enlarged scales between the last row of
ventral scales and anteriormost precloacal scale (versus last
ventral scales and anteriormost precloacal scale separated
by at least one row of small granular scales in H. guentheri
and H. laevis; see Fig. 7); it can be further distinguished
from H. laevis by having a pair of dorsolateral stripes (versus only paravertebral and lateral stripes in H. laevis) and
a pair of paravertebral stripes confned to enlarged dorsal plates (versus paravertebral stripes not confned to enlarged dorsal plates in H. laevis).
Etymology: Te specifc epithet “ngalangi” is a noun in apposition and is given in honor of the Ovimbundu Kingdom of Ngalangi, which dominated northern Huila Province and had its capital in present day Caconda. Te Kingdom of Ngalangi was dismantled by the Portuguese during
the Portuguese-Ovimbundu wars in the late 1760s. We suggest “Ngalangi Gliding Lizard” and “Lagartixa Planadora
Galangue” as the English and Portuguese common names,
respectively.
Parrinha, D., M. P. Marques, F. M. P. Gonçalves, A. Tiutenko, A. M. Bauer and L. M .P. Ceríaco. 2025. The Genus Holaspis (Squamata: Lacertidae) in Angola: A Tale of forgotten specimens and disappearing forests, with the Description of A New Species. SALAMANDRA. 61(1); 53-69.
