Afroedura donveae, Branch & Schmitz & Lobón-Rovira & Baptista & António & Conradie, 2021

Branch, William R., Schmitz, Andreas, Lobon-Rovira, Javier, Baptista, Ninda L., Antonio, Telmo & Conradie, Werner, 2021, Rock island melody: A revision of the Afroedura bogerti Loveridge, 1944 group, with descriptions of four new endemic species from Angola, Zoosystematics and Evolution 97 (1), pp. 55-82 : 55

Afroedura donveae sp. nov. Iona Flat Gecko Osga-achatada do Iona Figures 5D , 9 ; Tables 3, 7

Synonym.

Afroedura bogerti - Haacke 2008:6, Huntley 2009:84, Rösler 2000:57, Barts and Haacke 2010:39, Jacobsen et al. 2014:456 & 468 (part), Branch et al. 2017b:157 (part), Marques et al. 2018: 177 (part), Branch et al. 2019a: 287 (part); Afroedura cf. bogerti - Agarwal et al. 2017:649; Afroedura bogerti (clade 1) - Branch et al. 2017a:146.

Holotype.

PEM R17937, adult female, collected from Omauha Lodge, 15 km south of Tambor (-16.20061, 12.40183, 341 m a.s.l.), Namibe Province, Angola, by William R. Branch, Werner Conradie, Krystal Tolley and John Measey on 18 January 2009.

Paratype.

PEM R17936, collected from Omauha Lodge, 15 km South Tambor (-16.20061, 12.40183, 341 m a.s.l), Namibe Province, Angola, by William R. Branch, Werner Conradie, Krystal Tolley and John Measey on 18 January 2009.

Additional material examined.

Males: TM 40508, TM 40512, TM 40516, TM 40518, collected from Tambor (-16.06667, 12.43333, 355 m a.s.l.), Namibe Province, Angola, by Wulf Haacke on 1 April 1971. Females: PEM R18041-2, collected 0.5 km south of Tambor (-16.07414, 12.43328, 352 m a.s.l.), Namibe Province, Angola, by William R. Branch, Krystal Tolley and John Measey on 23 January 2009; TM 40509-11, TM 40513-5, TM 40517, TM 40536-8, collected from Tambor (-16.06667, 12.43333, 355 m a.s.l.), Namibe Province, Angola, by Wulf Haacke on 1 April 1971.

Additional referred material

(not examined). TM 40519-20, collected from Tambor (-16.06667, 12.43333, 355 m a.s.l.), Namibe Province, Angola, by Wulf Haacke on 1 April 1971; FKH 0341-2, collected from Omauha Lodge (-16.20061, 12.40183, 338 m a.s.l.), Namibe Province, Angola, by Pedro Vaz Pinto on 3 October 2019; CAS:HERP 263012-3, collected from Omauha (-16.19858, 12.40073, 338 m a.s.l.), Namibe Province, Angola, by Luis M.P. Ceriaco, Suzana Bandeira and Isham Agarwal on 25 and 27 November 2017; CAS:HERP 248780-1, collected 0.5 km south of Tambor (-16.07414, 12.43328, 352 m a.s.l.), Namibe Province, Angola, by William R. Branch, Krystal Tolley and John Measey on 23 January 2009.

Etymology.

This gecko is named after Donvé Branch, WRB’s wife, with the following personal quote: "This, the most beautiful of all the Angolan flat geckos, is named for my wife, Donvé Branch ( ‘Dove’) who bore the long periods I was away on fieldwork, and to whose nest I returned, and surrounded me with love until the end". The name is constructed in the feminine singular genitive.

Diagnosis.

A member of the greater ' Afroedura transvaalica ' group as it possesses two pairs of enlarged scansors per digit and a strongly verticillate and flattened tail ( Jacobsen et al. 2014). Part of the A. bogerti -group which differs from other members of the ' Afroedura transvaalica ' group by having less than 78 mid-body scale rows (vs. 97-102 in A. gorongosa , 113-120 in A. loveridgei , 102-119 in A. transvaalica ); by the rostral bordering the nostril (nostril excluded from rostral in A. loveridgei ); by the anterior nasals always in contact (separated by 1-3 granules in A. gorongosa ; always in broad contact in A. loveridgei ; usually in broad contact in A. transvaalica ~ 3-18%); and in having 11-14 scales between the anterior borders of the eyes (19-22 in A. gorongosa ; 15-19 in A. loveridgei ; 15-20 in A. transvaalica ) (comparative data fide Branch et al. 2017a).

Afroedura donveae sp. nov. differs from other members of the A. bogerti -group by a combination of the following characters (see Tables 3 , 4 ): 64-78 (mean 72.8) mid-body scale rows (69-77 [mean 73.5] in A. bogerti , 76-88 [mean 79.3] in A. wulfhaackei sp. nov., 73-86 [mean 80.3] in A. vazpintorum sp. nov., 73-78 [mean 74.8] in A. praedicta sp. nov.); by the anterior nasals always in contact (similar to A. vazpintorum and A. praedicta sp. nov.; in contact in ~ 33% of A. bogerti ; in contact in ~ 68% of A. wulfhaackei sp. nov.); in each verticil having 5-6 (mean 5.5) ventral and 6-7 (mean 6.6) dorsal rows of scales (5-6 [mean 5.0] and 6-7 [mean 6.1] to A. vazpintorum sp. nov.; 4 and 5 in A. bogerti and A. praedicta sp. nov., 4-5 [mean 4.0] and 5-6 [mean 5.1] in A. wulfhaackei sp. nov.); ventral surfaces immaculate (similar to A. vazpintorum sp. nov.; greyish with black spots in A. bogerti , A. wulfhaackei sp. nov. and A. praedicta sp. nov.); larger average adult size 57.6 mm SVL (versus 50.0 mm in A. bogerti , 51.7 mm in A. wulfhaackei sp. nov., 51.3 mm in A. vazpintorum sp. nov.; 49.9 mm A. praedicta sp. nov.). Afroedura donveae sp. nov. differs more specifically from its sister lowland species A. vazpintorum sp. nov. in being larger (57.6 mm versus 51.3 mm average SVL) and having lower mid-body scale counts (64-78 [mean 72.8] versus 73-86 [mean 80.3]), higher numbers of precloacal pores (11-12 [mean 11.5] versus 9-11 [mean 10.2]), bolder colouration and distinct tail banding (versus duller colouration and less distinct tail banding).

Holotype description.

Adult female: SVL 61.0 mm; tail 59.0 mm (full original tail), with a small mid-ventral incision for the removal of liver sample. Measurements and meristic characters of holotype presented in Table 7 . Head and body dorsoventrally compressed; HL 13.6 mm, HW 11.4 mm, broadest at posterior level of eye and 1.19 times longer than wide. Eyes large (3.4 mm wide), pupil vertical with indented margins; circumorbital scales small and smooth, elongated at upper anterior margin, upper three posterior scales with small upward pointing spines. Snout rounded, 5.6 mm long, longer than distance between eye and ear openings (4.5 mm). Scales on top of snout smooth, rounded, equal in size, with no intervening minute granules. Scales on snout slightly larger than those on back of head or nape. Scales on eyelids larger than those on the crown, 5 scales deep from circumorbital scale to crown. Nostril pierced between rostral, three nasal scales; 1st supralabial narrowly excluded from nostril; the supranasals are much larger than the subequal smaller postnasals, in broad contact with each other. Nostrils slightly elevated. Rostral roughly rectangular, but with its upper edges elongated due to extensions to the nostril. Nine supralabials on each side, the labial margin flexing upwards at the rictus (approx. mid-orbital position), with 1-2 minute scales proximal to the flexure. Ten infralabials on either side, with a small scale proximal to the flexure. At the lip, mental slightly narrower than adjacent infralabial, 63% of rostral and in contact with three distinctly elongated postmental scales. Scales on throat much smaller than those on belly, scales touching infralabials larger. Thirteen scales across the crown at level of front of eyes; 11 scales between nostril and front of eye; 13 scales from ear to eye; 74 scales around mid-body. Ear opening deep, oblique and roughly oval, only half as high as wide (0.4 × 0.9 mm). Scales on dorsum smooth, non-overlapping, largest at mid-body, smaller on nape and tail base. Scales on ventrum flattened, not overlapping, more-or-less ovate at mid-ventrum, twice the size of lateral granules and 1.5 times the size of scales along the dorsal mid-line. Original tail slightly dorsoventrally flattened and distinctly verticillate (16 whorls in total), with obvious lateral constrictions; each verticil comprising 7 rows of imbricate scales dorsally and 6 rows of imbricate scales ventrally, with ventral scales approximately twice the size of those on the dorsal surface. Limbs well-developed, hindlimbs slightly longer than forelimbs, both without obvious mite pockets at posterior margin of limb insertions; mite pockets present on anterior margin of hindlimbs. All digits with a large pair of distal scansors, separated by a large, curved claw and followed after a large gap (twice length of terminal scansor) by a smaller pair of scansors; infero-median row of digital scales enlarged transversely, particularly towards the scansors, where the terminal scale adjoining the first pair of scansors may be medially constricted, swollen and scansor-like; 8 enlarged scale rows under 4th toe.

Paratypes and additional examined material variation.

SVL varied from 49.1-55.7 mm; original tail length 26.5-59.0 mm, 0.78 times SVL; head length 1.13-1.46 times head width; snout 1.99 times diameter of eye (see Table 7 for more measurements and scale counts of type series). Supranasals always in contact; the first upper labial and rostral always enters the nostril and the width of the rostral at the lip margin is always wider than that of the mental; 2-3 postmental scales (except PEM R18401 with only one); supralabials 8-10, infralabials 8-11; scales between anterior edges of eyes 10-13; scales between nostril and anterior edge of orbit 8-12; scales from ear to eye 11-14; scales around mid-body 64-78; subdigital lamellae on 4th toe 6-8; dorsal scales per tail verticil 6-7 (mean 6.6); ventral scales per tail verticil 5-6 (mean 5.5); precloacal pores 11-12.

Colouration.

In life (holotype PEM R17937, Fig. 5D ): Yellowish above, brighter anteriorly, with nine irregularly-shaped darker brown to black crossbars from the occiput to the sacrum, each separated by thinner (3-4 scales deep), light yellow crossbars; head with dark brown-black blotches on the crown with intervening pale yellow colouration; dark brown bar from nostril across the upper margins of the ear opening, connecting with dark brown lateral bar on the neck; a thin pale yellow canthal stripe extends on both sides from the nasal region to anterior margins of eye, continuing posteriorly from the eye on to the nape; upper and lower labials light grey with diffuse brown edges; lateral sides of the body with a mix of dark grey and yellow blotches; limbs yellowish above with scattered darker grey markings; tail (original) with irregular dark brown bars, separated by yellow bars anteriorly, posteriorly with black and white bars; iris dark black with irregular golden spots, a black, narrow, elliptical, crenulate-edged pupil with black reticulation; ventrum uniform beige with scattered brown specks on lateral edges only; ventrally, limbs with scattered brown spots. In preservative (holotype PEM R17937, Fig. 9 ): dorsum with nine irregularly spaced dark brown crossbars from the occiput to the sacrum with beige intervening blotches; dorsally, arms and legs darkly barred; tail with nine dark brown bars, bolder towards the tip; dorsally, head with mottled dark brown scales; a light beige canthal stripe from nostril to anterior corner of eyes, continuing from the posterior part of the eye to above the ear opening; dark brown bar running from the nasals above the ear opening to the neck; light beige stripe (one-scale-wide) from above the supralabials to the ear opening (two-scales-wide); supralabials ventrally dark brown-edged; infralabials with scattered dark brown markings dorsally; ventrum is mostly immaculate, with dark brown spots ventrally on the arms and legs; ventrally, tail with nine dark brown bars, bolder posteriorly. Variation. Similar colouration and patterning as to the holotype. Dorsal crossbars are often fused to form 2-3 dark brown, X-shaped crossbars. Original tails with 6-7 broad, dark brown to black bars, separated by light beige to white bars; some specimens with fine one-scale-wide black bar separating the lighter bars. Regenerated tails with fine dark brown mottling. Juveniles with more sharply-defined patterns.

Natural history and habitat

(Fig. 4D ). One or two elongated white eggs were laid on limestone rock, to which they adhere in captivity; eggs measure 12.9-14.7 mm (mean 13.8 mm) × 10.5-12.1 mm (mean 11.6 mm) (n = 5) and hatch after 88-92 days, with hatchlings measuring 30.2-30.9 mm SVL and 26.5-27.9 mm tail length (n = 5) (Barts and Haacke 2010). A rupicolous species living in crevices between rocks and under flakes of exfoliating rock amongst larger granite boulders, at elevations of 340-355 m a.s.l. in the arid Namib Desert. It appears to be associated with large granite outcrops in semi-desert shrublands, along the drier fringes of the Pro-Namib. Vegetation includes Senegalia (= Acacia ) mellifera, Senegalia spp., Commiphora sp., Boscia foetida and Salvadora persica .

Distribution and conservation.

Currently known only from the south-western parts of Namibe Province in Angola, in granite formations around Tambor and on the right bank of the mid-Curoca River (Fig. 1 ). The species remains poorly known, but it is probably stable in numbers as the local habitat is currently not threatened. It likely occurs in Iona National Park.

Figures

Figure 1. Digital elevation map showing the predicted distribution of the five newly-recognised species of Afroedura occurring in Angola (data for A. wulfhaackei sp. nov. also contain the morphologically-indistinguishable Afroedura sp. 5 - 7 clades). Confirmed locality records are indicated by solid circles, with type localities indicated by stars. Coloured polygons indicate potential distribution areas with more than 90 % of climatic habitat suitability.

Figure 4. Typical habitat of Angolan Afroedura. A. Namba area (A. bogerti); B. Mt Sandula (Afroedura sp. 5); C. Serra da Neve (A. praedicta sp. nov.); D. Omauha Lodge (A. donveae sp. nov.); E. Farm Mucungo (A. vazpintorum sp. nov.); F. Bimbe (A. vazpintorum sp. nov.). Photos: A. Javier Lobon-Rovira; B, D, E. William R. Branch; C. Pedro Vaz Pinto; F. Ninda L. Baptista.

Figure 5. Live photos of Angolan flat geckos: A. Afroedura bogerti (PEM R 24187); B. Afroedura wulfhaackei sp. nov. (paratype PEM R 24232); C. Afroedura praedicta sp. nov. (holotype NB 854); D. Afroedura donveae sp. nov. (holotype PEM R 17937); E. Afroedura vazpintorum sp. nov. (holotype PEM R 24118); F. Afroedura vazpintorum sp. nov. (NB 0745); Photos: A, B, D, E. William R. Branch; C, F. Pedro Vaz Pinto.

Figure 9. Holotype of Afroedura donveae sp. nov. (PEM R 17937) from Omauha Lodge, 15 km south of Tambor, Namibe Province, Angola. Photos: Werner Conradie.