Spinomantis nussbaumi, Cramer & Rabibisoa & Raxworthy, 2008

Cramer, Abigail F., Rabibisoa, Nirhy H. C. & Raxworthy, Christopher J., 2008, Descriptions of two new Spinomantis frogs from Madagascar (Amphibia: Mantellidae), and new morphological data for S. brunae and S. massorum, American Museum Novitates 3618 (3618), pp. 1-24 : 14-19

Spinomantis nussbaumi , new species

Figures 2 , 4 , 5

HOLOTYPE: AMNH A167949 ( RAX 5934 ), adult male, with muscle and skin removed from left thigh for a tissue sample, collected 27 February 2003, Befosa River–Antetikalambazaha, Tsaratanana Massif, Bealanana Fivondronana , Mahajanga Province, 1650 m, 14 ° 10 9 27 0 S, 48 ° 56 9 42 0 E, by S.D. Mahaviasy, N. Rabibisoa, and N. Rakotozafy.

PARATYPES: AMNH A167947–48 ( RAX 5824 , 5933 ) , A167950–51 ( RAX 5975–76 ), collection data as the holotype except AMNH A167947 , 24 February 2003 ,1580 m; AMNH A167950–51 , 28 February 2003 , 1620 m.

DIAGNOSIS: A large-sized Spinomantis (adult male SLV 47–57 mm), with type 2 femoral glands that in preservative are lighter in coloration than the surrounding skin in breeding males; vomerine teeth; END / NSD # 1.8 ; dorsal body pattern composed of irregular darker shaped blotches; throat white (in life and preservative); a singular subgular vocal sac in males; SVL / FT # 1.4 ; inner and outer metatarsal tubercles; well-developed foot webbing, with only 0.25–0.5 of the distal phalange free of webbing on the exterior margin of toe 3, and only 1.0–1.5 distal phalanges free of webbing on the internal edge of toe 4 .

Spinomantis nussbaumi can be distinguished from all other Spinomantis species by the following characters. Spinomantis aglavei , S. fimbriatus , S. massorum , S. tavaratra , and S. phantasticus all have hind limb dermal spines that are absent in S. nussbaumi . Spinomantis bertini is much smaller (males SVL 22– 23 mm), and has only rudimentary webbing on the hind feet. Spinomantis elegans and S. microtis lack male femoral glands, and in addition, S. elegans lacks an outer metatarsal tubercle and S. microtis has completely webbed feet. Spinomantis guibei has distinctive markings: the ventral surface of the limbs are white with black blotches and the dorsal body has longitudinal dark lines, both of which are absent in S. nussbaumi . Spinomantis guibei also has more reduced webbing: the internal margin of toe 4 has three phalanges without webbing compared to 1–1.5 for S. nussbaumi . Spinomantis brunae can be distinguished by its smaller adult male body size (SVL 32–35 mm), reticulated dorsal body pattern, dark throat color, proportionally shorter snout ( S. brunae, END /NSD. 1.8, S. nussbaumi END /NSD # 1.8), and proportionally shorter foot length ( S. brunae SVL /FT $ 1.4, S. nussbaumi SVL /FT # 1.4). S. peraccae can be distinguished by its smaller adult male SLV ( S. peraccae 35– 46 mm, S. nussbaumi 47–57 mm; table 5) pale yellow throat color in preservative, lessdeveloped toe webbing with the exterior margin of toe 3 with 0.75–1.0 phalanges without webbing ( S. nussbaumi 0.25–0.5), and femoral gland color that is the same as the surrounding skin in preservative.

DESCRIPTION OF HOLOTYPE: Adult male in an excellent state of preservation with a singular subgular vocal sac, distinct femoral glands, and mature whitish-yellow testes, measuring 7.9 X 1.7 mm. A tissue sample of muscle has been removed from the left thigh.

Head smooth dorsally, with a faint longitudinal intraocular ridge. Head width 1.41 times head length. Head length 0.26 times SVL. Canthus rostrum sharp edged. A weak ridge starts posterior to nostril and runs through the loreal region to the lower anterior eye orbit. Internarial distance 0.30 times head width. Nostrils open laterally. Pupil round. Eye to nostril distance 1.50 times nostril to snout distance and 0.85 times eye diameter. Tympanum well defined, diameter 0.56 times eye diameter. Supratympanic ridge present, arching smoothly from posterior of eye to above the forelimb insertion point. Vomerine teeth present and vomerine bone triangular in shape.

Arms slender and smooth with forearm length 0.25 times SVL. No dermal spines on arms, legs, or body. Hand length (including disks) 0.36 times SVL with a trace webbing between digits, never extending beyond basal phalange. Relative finger lengths 1, 2, 4, 3. Fingers and toes with enlarged, triangular disks. Disk of third toe 1.8 times wider than terminal phalange. Dorsum and flanks with fine granular skin. Venter weakly granular. No enlarged tubercles on body or around cloaca.

Tibio-tarsal extension reaches between eye and snout tip. Thigh length 0.49 times SVL. Ventral surface of thigh weakly granular, all other leg surfaces smooth. Type 2, oval femoral glands differentiated and distended, measuring 9.8 X 5.0 mm, separated by 2.9 mm. In external view approximately 65 granules with no central pore visible. In internal view, approximately 120 granules. Granules translucent with opaque center. Lower leg 0.53 times SVL. Foot , including tarsus, 0.80 times SVL. Inner and outer metatarsal tubercles present, with round outer metatarsal tubercle 0.5 mm in diameter and elliptical inner metatarsal tubercle 2.1 mm in length. Relative toe lengths 1, 2, 5, 3, 4. Foot webbing I 0.5 – 1 II 0.25 – 1 III 0.5 – 1.5 IV 1 – 0.75 V.

TABLE 5 Morphometric data for Spinomantis nussbaumi , new species, and S. peraccae . All measurements in mm. BM specimen data from Andreone et al., (1998).

COLORATION IN PRESERVATIVE: Head dorsally and laterally dark brown with a darker brown, broken cross-shape marking on the posterior head, with the anterior arms of the cross reaching the supraocular regions. Iris dark brown. Tympanum light brown. Dorsum dark brown with darker brown spots forming two dorsolateral lines. Flanks dark brown with a yellowish-white spots. Arms brown with four dorsal darker brown transverse stripes of uneven width. Legs brown with nine darker brown transverse stripes of uneven width. When in sitting posture, dorsal stripes on the hind limbs line up, forming three longitudinal stripes. Throat white with small dark brown spots mostly concentrated on the lower lip margin. Venter yellowish white with dark brown spots in the pectoral region and anterior belly, and fading into pale-brown points on the posterior belly. Ventral arms and legs uniform brown, except for the femoral glands that are paler brown.

COLORATION IN LIFE: As in preservative, except that some green and greenish-brown pigment is present in life, forming spots on the head and body.

VARIATION: Morphometric variation is summarized in table 5. All specimens agree with the holotype description with the following exceptions. The supratympanic ridge has a sharp bend posterior to the tympanum in AMNH A167950 and A167951. Femoral glands vary in size from 9.2–15.5 length X 4.2–6.0 mm width, separated by 0.5–3.2 mm, with approximately 45 to 100 granules visible in external view. Inner metatarsal tubercles range from 1.5–1.9 mm in length. Foot webbing variation: I 0.25 to 0.5 – 1 II 0.25 – 1 to 1.25 III 0.25 to 0.5 – 1 to 1.5 IV 1 to 2 – 0.25 to 0.75 V.

AMNH A167947 and A167950 have a lighter grey-brown dorsum with more defined dark brown patterning. In these specimens there is a transverse intraocular stripe that connects to a medial longitudinal stripe that extends to the dorsal pectoral region. This longitudinal stripe then divides into two longitudinal dorsolateral stripes of uneven width that terminate at the lower back (fig. 5). AMNH A16750 also has small pale brown spots on the dorsal-posterior proximal region of each thigh. AMNH A167948 and A167951 have the intraocular transverse stripe and the medial stripe, and have scattered fine white spots on the posterior flanks. Spotting on the venter varies from a few small spots, as in AMNH A167947, to extensive blotching, as in AMNH A167948.

The female and juvenile morphology is unknown.

ETYMOLOGY: The specific name nussbaumi honors Ronald A. Nussbaum for his substantial contributions to our knowledge of the Malagasy herpetofauna.

DISTRIBUTION: Known only from the type locality: Befosa River–Antetikalambazaha , Tsaratanana Massif, in northern Madagascar. This species was found in rainforest between 1580–1650 m elevation .

REMARKS: All specimens were collected at night between 2100–2330 hours, on leaves at 1–3 height, overhanging or at the edge of the Befosa River. AMNH A167947 was found calling at the time of capture. At higher elevation at Tsaratanana, we also found specimens of S. peraccae . However, the type locality for S. peraccae is Ivohimanitra ( Boulenger, 1896) in southeast Madagascar (Tanala Region), and based on the geographic variation that is evident within this complex, this suggests the potential for additional species diversity. To facilitate the diagnosis of S. nussbaumi compared to S. peraccae , we report morphometric variation within both species in table 4, which includes the holotype of S. peraccae . Additional morphological data for S. peraccae is given by Glaw and Vences (1994) and Andreone et al. (1998).

IDENTIFICATION KEY TO SPINOMANTIS

This key will identify Spinomantis species for all adult male specimens (the only representative material known for some species), although many characters should also identify female and juvenile specimens.

1. No dermal spines on hind limbs......... 2

— Dermal spines present on hind limbs..... 8

2. Adult male SVL, 24 mm; rudimentary webbing on hind limbs; limbs with prominent and narrow dark transverse bands........................ Spinomantis bertini

— Adult male SVL. 24 mm; developed webbing on hind limbs; limbs may lack prominent and narrow dark transverse bands......... 3

3. Outer metatarsal tubercle absent; adult male SVL 52–60 mm; femoral glands absent in adult males; body dorsally marked by large distinct dark spots with pale borders...................... Spinomantis elegans

— Outer metatarsal tubercle present; adult male SVL 29–57 mm; femoral glands may be present in adult males; body dorsally may lack distinct dark spots with pale borders 4

4. Toes completely webbed; adult male SVL 34– 56 mm; femoral glands absent in adult males................. Spinomantis microtis

— Toes incompletely webbed; adult male SVL 29– 57 mm; femoral glands present in adult males.......................... 5

5. Ventral surface of hind limbs white with distinct large black spots; dorsal body with longitudinal black lines; adult male SVL 29– 35 mm ............. Spinomantis guibei

— Ventral surface of hind limbs not white and without distinct large black spots; dorsal body spotted, and usually lacks longitudinal black lines; adult male SVL 32–57 mm .. 6

6. Adult male SVL, 35 mm; body dorsally with a reticulated pattern of round dark spots; dark brown throat with light spots; NND/TD # 1.5; END/NSD. 1.8; SVL/FTL $ 1.4...................... Spinomantis brunae

— Adult male SVL. 34 mm; body dorsally lacks a reticulated pattern of round dark spots; light colored throat with dark spots; NND/ TD $ 1.7; END/NSD # 1.8; SVL/FTL # 1.4............................ 7

7. Adult SVL 33–46 mm; interior surface of toe 3 with 1.5 to 2 phalanges free of webbing; yellowish-white throat in preservative; lower flanks light with dark spots; adult male femoral glands same color as surrounding skin............. Spinomantis peraccae

— Adult SVL 47–56 mm; interior surface of toe 3 with 1 to 1.5 phalanges free of webbing; bright white throat in preservative (and life); lower flanks dark with white spots; adult male femoral glands lighter in color than surrounding skin... Spinomantis nussbaumi

8. Adult with dermal spines $ 0.5 mm in length above the eyes, and with prominent dermal spines on head and body........................... Spinomantis phantasticus

— Adult lacks dermal spines $ 0.5 mm in height above the eyes, and without prominent dermal spines on head and body....... 9

9. Adults with dermal spines. 1 mm in length on tarsus; dermal spines may have multiple points; dermal spines always present on arms.......................... 10

— Adults lacks dermal spines. 1 mm in length on tarsus; dermal spines on hind limb with single points; dermal spines may be absent on arms.......................... 11

10. Adult male SLV $ 40 mm; END/NSD $ 1.5............... Spinomantis aglavei

— Adult male SLV, 40 mm; END/NSD, 1.5............. Spinomantis fimbriatus

11. No dark spots on throat or venter; adult NSD. 2.1 mm; tibio-tarsal extension reaches between the eye and nostrils; interior surface of toe 4 with 0.75 to 2 phalanges free of webbing; exterior surface of toe 4 with 1 to 2 phalanges free of webbing........................... Spinomantis massorum

— Dark spots on throat and/or venter; adult NSD, 2.1 mm; tibio-tarsal extension reaches nostrils to beyond snout tip; interior surface of toe 4 with 2 to 2.5 phalanges free of webbing; exterior surface of toe 4 with 2 to 2.5 phalanges free of webbing.......................... Spinomantis tavaratra

Figures

Fig. 2. Localities for the new and redescribed Spinomantis species.

Fig. 4. Spinomantis nussbaumi, new species, and S. peraccae. A. Dorsal views of S. nussbaumi, new species (above, left to right): AMNH A167949, 167950, 167948; and S. peraccae (below, left to right): AMNH A167915, 167929, 167932, UMMZ 213265. B. Ventral views of S. nussbaumi, new species (above, left to right): AMNH A167949, 167950, 167948; and S. peraccae (below, left to right): AMNH A167915, 167929, 167932, UMMZ 213265.

Fig. 5. Dorsal view of Spinomantis nussbaumi, new species AMNH A167950.