Lygodactylus wojnowskii, Malonza, Patrick K., Granthon, Carolina & Williams, Dean A., 2016

Malonza, Patrick K., Granthon, Carolina & Williams, Dean A., 2016, A new species of dwarf gecko in the genus Lygodactylus (squamata: Gekkonidae) from central Kenya, Zootaxa 4061 (4), pp. 418-428 : 423-425

Lygodactylus wojnowskii sp. nov.

Mt. Kenya dwarf gecko ( Fig. 3 )

Holotype. NMK L3383/2 (Field No. PK176), adult male; in the vicinity of Chogoria Town, Meru South in Tharaka-Nithi County, Kenya (0°14’ S, 37°37’ E); collected 14 June 2010 by Danston Munene.

Paratypes. NMK L3383/3 (Field No. PK177), L3383/4 (Field No. PK178), adult males; L3383/1 (Field No. PK175), L3383/5 (Field No. PK179), L3383/6 (Field No. PK180), L3383/7 (Field No. PK181), L3383/8 (Field No. PK182), L3383/9 (Field No. PK183), L3383/10 (Field No. PK184), adult females; all collected in the same area as the holotype by the same collector. NMK L3213/1 (Field No. H162), L3213/2 (Field No. H197), adult males same locality as holotype, collected June 2009 by David Wojnowski.

Non-type material. NMK L439, 436, 441 and 380/1, adult males; L380/2 (female); Nyambene Hills, Meru North in Meru County, Kenya, possibly at Igembe area; collected in 1969 by Jerry Rillings.

Etymology. The specific epithet wojnowskii is given in honour of Dr. David Wojnowski currently at Georgia State University, USA, who collected the two paratype specimens in June 2009.

Diagnosis. Lygodactylus wojnowskii sp. nov. differs from its closest species L. mombasicus in having a different dorsal head pattern which has a Y-shaped pale stripe. While the throat of both species is dark or black, that of female Lygodactylus wojnowskii sp. nov. bears a chevron and a characteristic “o” shaped white chin spot. The two supranasals in L. wojnowskii sp. nov. are separated by 3 scales while in L. mombasicus they are separated by one scale.

Lygodactylus wojnowskii sp. nov. is assignable to the picturatus group on the basis of the following combination of characters: a large, undivided mental scale and subcaudal scales with the median row strongly enlarged transversely. Lygodactylus wojnowskii sp. nov. may be specifically diagnosed by possessing a combination of the following characters: regular head pattern, male throat black, that of female with two chevrons, six post-postmentals, no striking sexual dichromatism. Its dorsal colour is very similar to L. mombasicus and to some extent to L. kimhowelli but the stripes on the head join to form a Y-shaped mark between the orbits unlike the ring-like blotch in L. mombasicus . Lygodactylus wojnowskii sp. nov. falls within the size range of both L. mombasicus and L. picturatus ( L. wojnowskii : males 35–38 mm SVL, females 30–38 mm; L. mombasicus : males 37–39 mm, females 34–35 mm; L. picturatus : males 38–39 mm; females 35–36 mm). Lygodactylus wojnowskii sp. nov. has greater number of post-postmentals of 6 versus 5 in L. mombasicus .

It differs from other members of the L. picturatus group from Kenya as follows: L. keniensis has irregular head stripes and no dark vertebral stripes, female throat with three chevrons; L. mombasicus females, despite having two chevrons on the throat, lack the white chin spot. The other members of picturatus group in Kenya are quite different: L. picturatus males have distinct yellow heads, both L. manni and L. guttularis have gray heads and an unstriped dorsum, and in L. scortecci the head is cream or yellow striped.

Description of holotype: NMK L3383/2 (Field No. PK176) adult male ( Fig. 3 ). SVL = 37.3 mm; TrunkL = 18.1 mm; TailL = 40.1 mm; HeadL = 13.7 mm; HeadW = 8.4 mm; OrbD = 2.4 mm; HeadL/SVL = 0.37; HeadW/ HeadL = 0.61, slightly elongate, depressed and slightly distinct from the neck, loreal region slightly flattened, canthus rostralis prominent ( Fig. 4 ). Scales on the snout, forehead and around the eyes homogeneous and granular. Eye very small and bead-like (OrdD/HeadL = 0.17), ear opening small and rounded. Body slightly elongate (TrunkL/SVL = 0.48). Rostral scale complete, wider ventrally than dorsally; two internasal scales separated by three scales, two postnasal scales smaller than the internasal scale, one supranasal; supralabials 8, infralabials 6. Fore and hind limbs relatively short; all digits moderately short and clawed; terminal phalanx of all digits curved, arising angularly from distal portion of expanded lamellae; scansors beneath each toe in straight transverse series, divided except for basal- and distal-most, which are single, five pairs of lamellae beneath fourth toe, 1st toe highly reduced lacking claw ( Fig. 5 ). Dorsal pholidosis homogeneous granules ( Fig. 3 ). Scales on the occipital and temporal region granular and of varying sizes. Ventral scales larger than dorsal, smooth, and imbricate. Midbody scale rows across belly (12–16), gular region with granular scales. Scales on the palm and sole smooth and imbricate.Tail with inconspicuous whorls and smooth granular scales, more or less rounded in transverse section and slightly longer than body length (TailL/SVL = 1.07); subcaudal scales larger, with a single median scale row greatly enlarged transversely and there are eight male precloacal pores ( Fig.6 ).

Paratype variation. Paratypes mostly similar to the holotype. Postmentals 3–4; Postpostmentals 5–7; infralabials 5–8; supralabials 7–9 and 2 internasals. NMK-L3383, has 5 pairs of scansors on the fourth toe ( Fig. 5 ).

Coloration in ethanol. Dorsum of trunk grayish. Head with three regular dark stripes on dorsum, the central one very short ending on the head, plus a dark stripe that runs from the nostril through the eye up to the shoulders. In addition there are two faded dark stripes that start from between the eyes and run in parallel on the back along the vertebral midline up to the tail base. Body venter cream-white; palms and soles cream ( Fig. 3 ). Throat of male black while that of the female has two chevrons and a characteristic white chin spot. Lygodactylus wojnowskii sp. nov. throat patterns and those of its close relatives, L. mombasicus , L. keniensis and L. picturatus are shown in Fig. 7 .

Color in life and sexual dimorphism. There is no well-marked difference in dorsal color of the body or size between the sexes. The belly is yellow, similar to many other pitucratus group species (e.g., L. picturatus , L. mombasicus , L. kimhowelli , L. manni , L. keniensis ). However, in L. wojnowskii sp. nov. the yellow continues down the tail well beyond the vent in males. Its dorsal color and pattern is quite different from its close relatives, L. mombasicus and L. keniensis ( Fig.8 ).

Natural history. Lygodactylus wojnowskii sp. nov. is an arboreal day gecko that inhabits hedgerows, small bushes, trees and fences covered by heavy vegetation. In Sagana River bridge area the species was found to also inhabit short fruit plants like pawpaw, mango, and citrus, among others. The species is strictly arboreal and is quite agile, jumping between nearby branches. In Chogoria it is sympatric and syntopic with the tropical house gecko Hemidactylus mabouia (Moreau de Jonnès).

Distribution and conservation status. Recently collected specimens of Lygodactylus wojnowskii sp. nov. have been found only from mid-altitude areas around Chogoria Town (1600 m), a place with a high human population. Older specimens are from Nyambene Hills, and possibly the Igembe area, where they were collected by Gerald (Jerry) Rillings, an American who used to teach in a local school. It is yet to be established whether it is present in the Chogoria block of the Mt Kenya Forest. The two sites are at similar elevations and it is likely that the species may be widely distributed in suitable habitat areas on the eastern lower slopes of Mt. Kenya from areas around Embu, Runyenjes, Chuka, through the Meru Town area, so as to connect with the Nyambene Hills population. Other recent specimens collected or photographed are from Chiakariga in Tharaka, Kindaruma and Masinga Dams in Machakos, Sagana River Bridge area-Mwea (00o 46.408’ S; 0 37o 16.073’ E, 1135 m), Miwani at Machakos town and Kenyatta University compound, Nairobi. Nairobi (1600 m) is at a similar elevation to Chogoria, whereas typical L. mombasicus are only found along the moist coastal strip of Kenya and are not found this far inland. This further suggests that the Nairobi specimen of L. mombasicus cited by Castiglia & Annesi (2011) was actually L. wojnowskii sp. nov. The full extent of the distribution of L. wojnowskii sp. nov. has yet to be established, but there is no doubt that it should occur in the neighboring areas north and south of Chogoria and the intervening areas towards the Nyambene Hills and towards Nairobi, since they possess similar ecological characteristics as the eastern slopes of Mt. Kenya. Therefore it is likely present in Mwea National Reserve which is within its presumed altitudinal range. Given that the species still exists in these densely populated areas demonstrates that it adapts well and is of least conservation concern.

Figures

FIGURE 4. Head of holotype of Lygodactylus wojnowskii sp. nov. (NMK L 3383 / 2). Left to right: dorsal view, lateral view, ventral view. Scale bar = 1 mm.

FIGURE 5. Ventral views of left foot of A) the holotype of Lygodactylus wojnowskii sp. nov. (NMK L / 3383 / 2) and B) female paratype NMK L 3383 / 6. Scale bar = 1 mm.

FIGURE 6. Holotype of Lygodactylus wojnowskii sp. nov. (NMK L / 3383 / 2): A) precloacal region showing series of eight pores (extent of pores marked with arrows), B) tail dorsum and tail venter. Scale bars = 1 mm.

FIGURE 7. Sexual dichromatism in throat pattern and scalation in Kenyan Lygodactylus picturatus group species. A) Lygodactylus wojnowskii sp. nov. holotype male NMK L 3383, paratype female NMK L 3383 / 8; B) L. mombasicus male NMK L 3237 / 1, female NMK L 1909 / 20; C) L. keniensis male NMK L 3372 / 1, female NMK L 3374; D) L. picturatus male NMK L 2249 / 2; female NMK L 2249 / 7. Scale bars = 1 mm.

FIGURE 8. Body c olor in life of Kenyan Lygodactylus picturatus group species. A) Lygodactylus wojnowskii sp. nov. venter of male from Chogoria, Photo by D. Wojnowski; B) dorsum of male from Sagana River Bridge; C) dorsum of male Lygodactylus mombasicus, Shimba Hills—Kwale; D) dorsum of male Lygodactylus keniensis, Lolldaiga Hills-Laikipia. Photos B – D by P. K. Malonza.

FIGURE 3. A) Dorsal and B) ventral views of the trunk of the holotype of Lygodactylus wojnowskii sp. nov. (NMK L 3383 / 2). Scale bar = 1 mm. C) Dorsal view of the preserved holotype showing dorsal color pattern.