Uroplatus kelirambo, Ratsoavina & Gehring & Scherz & Vieites & Glaw & Vences, 2017

Ratsoavina, Fanomezana M., Gehring, Philip-Sebastian, Scherz, Mark D., Vieites, David R., Glaw, Frank & Vences, Miguel, 2017, Two new species of leaf-tailed geckos (Uroplatus) from the Tsaratanana mountain massif in northern Madagascar, Zootaxa 4347 (3) : -

Uroplatus kelirambo sp. nov.

( Figures 5–6 )

Remark. This new species was previously referred to as Uroplatus sp. E by Raxworthy et al. (2008b), as U. sp. 2 by Ratsoavina et al. (2011), and as U. ebenaui [Ca2] by Ratsoavina et al. (2012, 2013, 2015).

Holotype. ZSM 641/2014 (field number DRV 6192 ), adult male with everted hemipenes, collected at the Matsaborimaiky camp site in the Tsaratanana mountain massif , Antsiranana Province, northern Madagascar, 14.1526°S, 48.9573°E, 2021 m above sea level, on the night of 13 June 2010, by D. Vieites, M. Vences, F. M. Ratsoavina, F. Randrianasolo, R. D. Randrianiaina, S. Rasamison, A. Rakotoarison, E. Rajeriarison and T. Rajoafiarison.

Paratypes. ZSM 642/2014 (DRV 6250) and ZSM 643/2014 (DRV 6251), two adult males, and ZSM 1832/ 2010 (ZCMV 12388), an adult female, all with same collection data as the holotype.

Etymology. The specific epithet kelirambo is composed of the Malagasy words for small (kely) and tail (rambo). The name refers to the small and very thin tail of this species, but also points to the movie character Rambo and his toughness. This species shares with other members of the U. ebenaui group a grim, Rambo-esque expression, and is tough, surviving at exceptionally high altitudes, unique among Madagascar’s nocturnal geckos. The name is an invariable noun in apposition.

Diagnosis. Uroplatus kelirambo sp. nov. is included in the Uroplatus ebenaui group of small-sized leaf-tailed geckos due to its triangular head with supraocular spines, laterally compressed body, and short tail. It differs from all members of the U. fimbriatus group ( U. fimbriatus , U. giganteus , U. henkeli , U. sikorae and U. sameiti ) and U. lineatus by its much smaller size (adult SVL 53.1–63.4 mm versus at least 85 mm), lack of lateral dermal fringes on any part of the body, and lateral compression of the body (versus depressed body shape with lateral integumentary fringes), and a relatively much shorter tail. The evident triangular head, rather smooth skin and short tail distinguish U. kelirambo from U. alluaudi , U. guentheri , U. malahelo and U. pietschmanni .

Within the U. ebenaui group, the blackish oral mucosa distinguishes U. kelirambo from U. fiera , U. finiavana and U. fotsivava (oral mucosa unpigmented). Furthermore, the new species differs from all species by the unique elongated shape and small size of its tail. In particular, it differs from U. finiavana , U. malama and U. phantasticus by a shorter tail (adult TAL/SVL 0.35–0.44 vs. 0.48 in U. finiavana , 0.72 in U. malama , and 0.62–0.76 in U. phantasticus ), and from U. fiera and U. fotsivava by a longer tail (adult TAL/SVL 0.35–0.44 vs. 0.28–0.34 in U. fiera and 0.15–0.32 in U. fotsivava ). It differs from all other nominal species of the U. ebenaui group by a narrower tail; this is obvious from the lower values of the ratio TAW/SVL (0.04–0.05 vs. 0.24 in U. malama , 0.16–0.20 in U. phantasticus , 0.11 in U. finiavana , 0.06–0.07 in U. fiera , 0.05–0.09 in U. ebenaui and 0.07–0.1 in U. fotsivava ), but especially in values of the ratio TAW/TAL (0.10–0.13 vs. 0.33 in U. malama , 0.25–0.29 in U. phantasticus , 0.23 in U. finiavana , 0.19–0.21 in U. fiera , 0.13–0.27 in U. ebenaui and 0.17–0.32 in U. fotsivava ).

In direct comparison to U. finiavana , the closest relative of U. kelirambo among the nominal species of Uroplatus , the new species is thus distinguished by its tail shape and size, and the pigmented (vs. unpigmented) oral mucosa.

Description of the holotype. Adult male in good condition with an intact tail and everted hemipenes. SVL 57.3 mm, tail length 25.4 mm, maximum tail width 2.5 mm, for further measurements see Table 1. Head triangular in dorsal view; snout length 5.1 mm; canthus rostralis indistinct; snout sloping weakly and continuously downward anteriorly; snout undepressed in lateral view (1.1 times longer than eye diameter); eyes large (eye diameter 4.8 mm), bulging slightly above dorsal surface of cranium, directed laterally, pupil vertical with crenate borders; ear opening very small (horizontal diameter 0.7 mm), its opening facing posterolaterally, but also posteroventrally (ear opening clearly visible in ventral view but not in dorsal view); nostrils laterally oriented; body somewhat laterally compressed, without lateral dermal fringes; limbs without fringes, forelimb reaches beyond tip of snout when adpressed forward, but is quite far from the groin when adpressed backwards along body (forelimb length/axilla– groin distance 24.6/29.8 mm = 83%), hindlimb reaches the axilla when adpressed forward along body (hindlimb length/axilla–groin distance 30.8/29.8 mm = 103%); tail length 44% of snout–vent length, almost without membranous borders of the tail, with just one small dermal spine on each side, with a slightly spatulate tail-tip.

Nares separated from each other by seven small granular scales, from the first supralabial by one scale, and from the rostral scale by one scale; first supralabial taller than the others; rostral entire, much wider than tall; mental scale very small, not differentiated from infralabial scales; 22/22 (right/left) true supralabials and 21/20 infralabials (as defined in methods above); no enlarged postmental scales or chin shields; dorsal and ventral scales of head, neck, body, limbs, and tail small, strongly granular, juxtaposed and largely of uniform size, except for some larger, interspersed and partly raised tubercles and except for the irregular lines on the head and body which consist of series of slightly enlarged scales. Two curved lines (rows of slightly enlarged scales) extending from the posterolateral parts of the head (nuchal region) converge on the neck forming a V-shaped pattern (neck triangular line). A weakly curved, moderately distinct, and weakly posteriorly extending line (also formed by a row of slightly enlarged scales) is present between the eyes and connects the supraocular spines. Three additional weaklyvisible transverse lines, consisting of slightly enlarged scales, are recognizable on the frontal region of the head.

A few well developed spines on the posterior part of the head (ca. 6), on hindlimbs (ca. 12 per limb), a dermal flap on each knee not bearing a spine; spines present on the elbow, three spines per arm; a long, pointed supraocular spine above each upper eyelid; posterior border of eye fringed. Axillary pits absent. Scales of the posterior ventral abdomen enlarged and arranged more uniformly than other scales, almost forming proper rows.

Hemipenes everted, bearing two lobes. Calyx with protuberance bearing honeycomb-like structures, especially on the asulcal side. Area of sulcus spermaticus is smooth. Each lobe with dense field of pointed papillae at its apex.

Coloration. After six and a half years of preservation in 70% ethanol, the color pattern remains the same as in the living animal ( Fig. 5 ) but its vivacity and intensity have faded slightly. All dorsal surfaces are brown in base color, mottled darker and lighter. The tail is creamy chocolate above, darkening to a brown tip. The head is also creamy chocolate above, with the V-shaped marking of the nape darkening toward its posterior tip, bordered by lighter brown, making the marking highly contrasting. The dorsum has delicate lines of cream and dark brown, generally parallel to the ribs beneath them. A few small dark brown flecks are present on the dorsum, but none of note. Two light cream markings defined by brown borders are present below each eye, one at the posterior corner and one at the mid-eye, both descending to the supralabials. The supralabials are generally beige in color, but a few are burnt umber. The infralabials weakly alternate between cream and burnt umber. The exterior shank from the knee to the outer foot is beige in color, strongly contrasting the rather dark brown of the rest of the leg and foot. A cream dorsomedial line runs from the pelvic region to the mid-dorsum. The venter, including the ventral limbs except the lower hindlimbs, is a lighter brown than the dorsum, and much less mottled. The ventral trunk bears several round cream spots defined by brown borders, with two pairs of such markings in the anterior pectoral region, and one small pair at the glenoid socket and other such spots on the mid and posterior abdomen. The tail is slightly darker below than above, and has an oblong cream fleck at its base. The oral mucosa is dark in preservative. In life the eye was beige with reddish and yellowish brown mottling.

Variation. In general, the paratypes agree well with the holotype in morphology. For measurements, see Table 1. The canthus rostralis of ZSM 643/2014 is quite distinct, but it is indistinct in all other type specimens. The number of head spines varies from four (ZSM 1832/2010) to eight (ZSM 642/2014 – 643/2014). Spines are always present on the elbow, but can be miniscule, and there can be almost no other spines on the arms (ZSM 1832/2010) or up to four spines per arm (ZSM 642/2014). The legs can have as few as five spines per leg (ZSM 1832/2010) to as many as seventeen (ZSM 642/2014). The oral mucosa is pigmented in all specimens. The supraocular spines of all paratypes are shorter than the holotype, and the line connecting them can be curved to a point. The hemipenes of ZSM 643/2014 strongly resemble those of the holotype; those of ZSM 642/2014 are not fully everted. The number of true supralabials ranges from 18 to 22, of true infralabials 17 to 21. Coloration is highly variable, as is typical of Uroplatus . ZSM 643/2014 is quite similar to the holotype, but the posterior trunk is darker than the chin, it lacks cream spots on the venter except at the base of the tail, it has a less distinct nape V and chevrons on the body, and it has large burnt umber spots, especially on the midline. ZSM 642/2014 is a light caramel brown in base color, with dark markings as in ZSM 643/2014, but a distinct nape marking as in the holotype; ventrally this specimen has dark chevrons on the chin and is mottled cream and brown, with paired cream spots on the posterior abdomen and one weak one on the throat. ZSM 1832/2010 is reddish brown in base color with large off-white blotches on the flanks and head, its ventral coloration similar to ZSM 642/2014, and possessing a triangle of three white spots at the base of the tail. It has only one marking below the eye. Tails of males can have two or three lateral spines, whereas females have a very narrow membranous border; again this indicates some degree of sexual dimorphism in tail shape (see Ratsoavina et al. 2015).

Distribution. The species is known from only a single site, the environments of Matsaborimaiky (named Matsabory Maiky by Rakotoarison et al. 2012), the second campsite along the trail to the peak of Maromokotro in the Tsaratanana Massif (the highest mountain in Madagascar). Here, specimens were collected in the environments of the campsite, and on the trail towards the third campsite, up to an estimated elevation of 2200 m a.s.l.

Natural history. All specimens of U. kelirambo were collected at sites close to Matsaborimaiky, on branches of small trees. The site is characterized by a wetland surrounded by a mixture of montane and bamboo trees. Classified as a humid montane forest, the canopy does not reach 20 meters height and trees are rather short, sinuous in shape and covered in lichen. The holotype of U. kelirambo was collected at night perching in a small tree at ca. 1.75 m height from the ground.

Figures

FIGURE 5. Dorsal views of preserved holotypes of (a) Uroplatus fotsivava sp. nov. and (c) U. kelirambo sp. nov., as well as (b, d) sulcal views of the everted hemipenes of the two species. Scale bars refer to the photos of the two specimens; hemipenis photos not to scale.

FIGURE 6. Photographs of specimens of Uroplatus kelirambo sp. nov. in life. (a) Male holotype ZSM 641 / 2014 (DRV 6192) from Matsaborimaiky; (b) female specimen from Matsaborimaiky, probably corresponding to one of the paratypes in the UADBA collection; (c-e) female paratype, ZSM 1832 / 2010 (ZCMV 12388) from Matsaborimaiky.