Kolekanos spinicaudus, Lobón-Rovira & Conradie & Baptista & Vaz Pinto, 2022
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publication ID |
https://dx.doi.org/10.3897/zookeys.1127.84942 |
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publication LSID |
lsid:zoobank.org:pub:1FA39C0E-21C3-4137-A0B3-CB08300CF6AC |
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persistent identifier |
https://treatment.plazi.org/id/80186811-4C1C-4F26-B791-0824BA79E221 |
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taxon LSID |
lsid:zoobank.org:act:80186811-4C1C-4F26-B791-0824BA79E221 |
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treatment provided by |
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scientific name |
Kolekanos spinicaudus |
| status |
sp. nov. |
Kolekanos spinicaudus sp. nov.
Figs 3 View Figure 3 , 4 View Figure 4 , 5 View Figure 5 , 6 View Figure 6 , 7 View Figure 7
Holotype.
MNCN 50769, adult male, with regenerated tail and incision in the ventral region, collected in Carivo (-13.19225, 13.42108, 362 m a.s.l.), Benguela Province, Angola, by Pedro and Afonso Vaz Pinto on 19 August 2021.
Paratypes.
MNCN 50766, adult male, collected from Ekongo (-13.24940, 13.20650, 636 m a.s.l.), Benguela Province, Angola, by Javier Lobón-Rovira and Pedro Vaz Pinto on 22 November 2021; MNCN 50767 & FKH-0845, adult females, with the same collecting data as the previous. FKH-0645 & FKH-0650, adult females, FKH-0647-8, adult males, MNCN 50768, subadult male, all with the same collecting data as the holotype.
Etymology.
The name " Kolekanos spinicaudus " is derived from the combination of the Latin words “spina” and “cauda”, that refers to the spiny appearance of the tail of the new species. The species epithet is used as a singular nominative adjective "- us ".
Diagnosis.
Kolekanos can be easily differentiated from other circum-Indian leaf-toed and African leaf-toed geckos, based on its ornamented tail (versus non-ornamented tail in the remaining genera). The new species differs from K. plumicaudus , based on the following characters: different ornamentation of the tail, being composed by modified scales on the margins of the original tail which resemble white lateral spines (versus feathered-like tail in K. plumicaudus ); broader head (minimum HW = 7.95 mm versus maximum HW = 7.35 mm in K. plumicaudus ); more robust body, with shorter forelimbs (versus thinner and more slender body in K. plumicaudus , Fig. 5 View Figure 5 ); proportionally larger snout to eye distance (SE mean 4.48 mm ± 0.34 s.e. versus 3.99 mm ± 0.22 s.e. in K. plumicaudus ) and interorbital distance (IO mean 4.14 mm ± 0.34 s.e. versus 3.33 mm ± 0.28 s.e. in K. plumicaudus ); and dorsal pattern is less contrasted, based on zig-zag black patches surrounded by lighter patches (versus dark blocks well contrasted, not surrounded by lighter patches in K. plumicaudus ). The new species can also be differentiated from K. plumicaudus by the following osteological characteristics: 1) larger jugal bone (versus reduced jugal); 2) more prominent lateral process of the postorbitofrontal (versus less prominent lateral process of postorbitofrontal); 3) more compressed premaxilla and maxilla bone on its dorsoventral profile and wider in the lateral profile of the bones; 4) ascending process of the premaxilla shorter (versus more elongated); 5) braincase compressed dorsoventrally (versus more rounded in K. plumicaudus ); 6) palatine length and width equal (versus unequal); 7) postero-lateral process of parietal rounded and slightly curved (versus flat postero-lateral process of parietal broad and flat that curves downwards posteriorly); 8) anterolateral process of the coronoid markedly enlarged (versus more reduced anterolateral process). Kolekanos spinicaudus sp. nov. also differs from K. plumicaudus by circa 24% (uncorrected p-distance) ND2 mitochondrial DNA.
Holotype description.
(Fig. 4 View Figure 4 ). Measurements and meristic characters of the holotype are presented in Table 3 View Table 3 . Adult male with a SVL of 44.59 mm and partially (2/3) regenerated tail, tail length (TL) 36.77 mm. Body moderately slender, nape distinct. Head slightly broader than the body and markedly compressed dorsoventrally (HH/HL = 0.27). Canthus rostralis smooth, almost absent. Eye diameter (2.35 mm), with vertical pupil and crenulated margin. Supraciliar scales small and rounded. Ear height (0.47 mm). Ear to eye distance larger than eye diameter (3.72 mm). Snout rounded and slightly pointed. Body relatively slender and elongated (TrunkL/SVL = 0.44). Fore- and hindlimbs moderate and stout, forearm large (FL/SVL 0.23), tibia short (CL/SVL 0.18). Digits elongated and clawed. All digits of manus and pes indistinctly webbed. All digits with granular basal scales and more distal widened divided lamellae. One pair of leaf-like terminal scansors. Number of scansors: 7-10-10-11-10 (right manus) and 7-10-10-11-10 (left manus)/7-9-11-11-10 (right pes) and 7-9-11-11-9 (left pes). Relative length of digits manus I <II <III <IV> V and pes I <II <III> IV> V. Scalation: Frontal scales granular and larger than occipital scales. Occipital scales small and granular. Rostral in direct contact with nostrils, 1st supralabials, supranasals and one internasal scales. 8/8 supralabial and 9/9 infralabials. First supralabial in contact with the nostril. Nostril circular and surrounded by rostral, 1st supralabial, supranasal and three reduced postnasals. Lower postnasal half the size of the upper postnasal and supranasal. Two rows of scales between supralabials and the orbit. Mental triangular and rounded posteriorly, with two small rounded postmental scales. 1st infralabial rectangular and slightly larger than mental. Gular scales small and granular. Ventral scales small and granular. Precloacal pores absent. The dorsal pholidosis present homogenous granular scales from head to tail. The first third of the original tail presents lateral whitish “spine-like” scales, being absent in the last portion of the tail. Post-cloacal scales slightly larger and quadrangular. Osteology: the skull (Fig. 3 View Figure 3 ) displays no co-ossification with the overlying skin. Nasals are fused. Single frontal. Paired parietals. Stapes imperforate. 14 scleral ossicles. 11 premaxillary tooth loci. 36-38 maxillary and 38 dentary tooth loci. Braincase elements fused. Postorbitofrontal arrow-shaped, with lateral process as long as anterior and posterior process. Parietal wider than longer. Jugal small, but visible.
Variation.
Variation in scalation and body measurements of the paratypes of K. spinicaudus sp. nov. are reported in Table 3 View Table 3 . All the material analysed agrees with the holotype description with the exception of the tooth loci, where the specimen MNCN 50766 presented a larger number in the tooth loci of maxilla and dentary (> 40).
Colouration.
In life (Fig. 5A View Figure 5 ): dorsal colouration varies from light pinkish to light brown, with black spots surrounded by lighter brownish regions disposed in zig-zag, from nape to tail. Dorsal reticulated light brownish colouration on tail and fore- and hind-limbs. Anterior part of the tail with marked hourglass-shaped pattern. Ventrum uniformly light cream pink from snout to posterior region of the cloaca. Tail slightly darker than the dorsum dorsally, being even darker in the ventral section, with white lateral spine-like scales on original tail. Last fourth portion of tail black. In preservative (After 4 months in preservation; Fig. 4 View Figure 4 ): dorsal pattern persistent as " in life " with dorsal colouration whitish-greyish. Dark section more marked.
Distribution.
(Fig. 6 View Figure 6 ). This species has only been found at two sites in a very restricted region, in southern Benguela Province. The area lies above the first elevational range recognised for southern Angola’s orographic relief, with specimens retrieved between 400 m and 650 m a.s.l. It can be broadly characterised as a rugged and transitional semi-arid landscape, albeit more vegetated and less arid than the coastal lowlands to the west and less mountainous and forested than eastern regions neighbouring the great escarpment. Despite its unique and unmistakable features, this species had eluded previous surveys conducted in coastal Benguela Province. In the last 5 years our team visited the same area at least five times preceding the discovery, spending at least two days per survey. Even though we found the species to be relatively common at the two referred sites, we failed to confirm its presence in several other locations with presumably suitable habitat, suggesting that it might be highly specialised and sensitive to local environmental conditions. It is possible for the species to be more common and widely distributed in poorly-surveyed regions to the southeast or north of its known range and we recommend further surveys in the region to address the conservation status of this poorly-known species.
Habitat and natural history notes.
(Fig. 7 View Figure 7 ). The local habitat, at both sites where the species was discovered, seems to be a transitional zone in coastal Angola, displaying a rich vegetation mosaic of acacia and Colophospermum mopane savannah, including Senegalia mellifera , Senegalia spp., Colophospermum mopane , Terminalia prunioides, Commiphora spp. and presence of succulents, such as Euphorbia spp. and Aloe littoralis . In contrast, and despite being known from a relatively wider region and across considerable elevational ranges, K. plumicaudus is found in much more arid and sparsely vegetated environments. The new species was mostly found at night foraging in the ecotone between the trees/bushes and moderate to large granite boulders. One individual (not collected) was retrieved while sheltering under a rock flake during the day, behaviour which has been documented for the closely-related K. plumicaudus ( Agarwal et al. 2017; Vaz Pinto et al. 2021). When not stretched horizontally, this species curls the tail laterally, but not upwards, while K. plumicaudus often erects the tail upwards and may wave the tip ( Agarwal et al. 2017). The first individual observed was seen running fast on the ground between a granite boulder and a tree, but more often, they were found perched on branches and once on a grass stem. Unlike K. plumicaudus , which readily jumps amongst thin branches when disturbed, K. spinicaudus sp. nov. seems to prefer to run along thicker branches or drop to the ground and run for safety. Two individuals were observed mating at night (18 August 2021 19 h 55 m) on a thin branch of Salvadora persica . One female specimen (FKH-0645) collected in November 2021 contained two well-developed eggs. This species has been found in syntopy with another Angolan leaf-toed gecko, Bauerius ansorgii . Finally, due to the complex biogeography of Angola, an updated and stabilized biogeographic classification, especially for south-western Angola, is still lacking. Current schemes depend on the authors interpretation and underlying data used (e.g. phytocoria, centres of endemism, realms, biomes, ecoregions) resulting in different units recognised and sharp boundaries ( Burgess et al. 2004; Dinerstein et al. 2017) which often do not match the situation on the ground. Thus, we cannot currently assign any specific biogeographic region to any of these two taxa and are anticipating a better review of Angolan biogeographic units through Huntley (in prep.) in the near future.
Conservation status.
The species seems relatively common, but highly localised. Although the general habitat does not appear to be threatened, more research is needed to confirm if the species’ distribution is larger than currently known. Therefore, following the IUCN Red List guidelines ( IUCN 2022), the species should be considered as Data Deficient (DD).
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