Spinomantis tavaratra, 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 : 10-14

Spinomantis tavaratra , new species

Figures 1E , 2 , 3

HOLOTYPE: AMNH A167935 ( RAX 4875 ), adult male, collected 11 April 2002 at Sorata Mountain, Vohemar Fivondronana , Antsiranana Province, 1300 m, 13 ° 41 9 9 0 S 49 ° 26 9 31 0 E, by S.D. Mahaviasy, N. Rabibisoa, and C.J. Raxworthy.

PARATYPES: AMNH A167936–37 ( RAX 4876 , 4962 ), collection data as the holotype except A167937, collected 12 April, 2002 ; AMNH A167933–34 ( RAX 3494 , RAX 3508 ), collected 6–7 December 2001, Ambolokopatrika River, Betaolana Corridor Forest, Andapa Fivondronana , Antsiranana, 1250 m, 14 ° 31 9 53 0 S, 49 ° 25 9 37 0 E by S.D. Mahaviasy, N. Rabibisoa, A. Rakotozafy, A. Razafimanantsoa, and A. Razafimanantsoa ; AMNH A157066 ( APR 380 ) and AMNH A157069 ( APR 440 ), collected 15–17 October 1996, Andampimbazaha Cascade, a tributary of Manantenina River, 10 km NW from Manantenina village , Marojejy Strict Nature Reserve , Sambava Fivondronana, Antsiranana Prov-

TABLE 3 Morphometric data for Spinomantis tavaratra , new species. All measurements in mm.

ince, 700–780 m, 14 ° 26.0 9 S, 49 ° 45.7 9 E, by A.P. Raselimanana; AMNH A157070–73 ( APR 722 , 752 , 754 , 812 ) collected 24–27 October 1996, Ambavanaomby, 11 km NW from Manantenina village, Marojejy Strict Nature Reserve , Sambava Fivondronana , 1100–1180 m, 14 ° 26.2 9 S, 49 ° 44.5 9 E, by A.P. Raselimanana ; UMMZ 212364–66 ( RAN 39769, 39776 , 39855 ) collected 21–24 November 1992 at the Manantenina River in the Marojejy Reserve, Sambava Fivondronana , Antsiranana Province, 650–700 m, 14.43 ° S, 49.76 ° E, by R. A. Nussbaum, C. J. Raxworthy, A. Razafimanantsoa, and A. Razafimanantsoa ; UMMZ 212367–68 ( RAN 39969–70 ) collected 27–30 November 1992 at Marojejy Reserve, Sambava Fivondronana , Antsiranana Province, 1300 m, 14.43 ° S, 49.76 ° E, by R. A. Nussbaum, C. J. Raxworthy, A. Razafimanantsoa, and A. Razafimanantsoa .

DIAGNOSIS: A medium-sized Spinomantis (adult male SLV 30–36 mm), with type 2 femoral glands in adult males; a singular subgular vocal sac in males; NSD, 2 mm; dark spots on throat and venter; inner and outer metatarsal tubercles; vomerine teeth; a tibiotarsal extension that extends between the nostril to beyond the snout tip, 2 to 2.5 phalanges free of webbing on the exterior 4th toe, and simple dermal spines, 1 mm length along the posterior margin of the tarsus (table 3).

Spinomantis tavaratra can be distinguished from the following species: S. peraccae , S. brunae , S. elegans , S. microtis , S. bertini , and S. nussbaumi sp. nov. by presence of dermal spines on the tarsus. Spinomantis tavaratra can be distinguished from S. phantasticus by the lack of supraocular dermal spines $ 0.5 mm and lack of other prominent spines on the head or dorsum. Spinomantis tavaratra can be distinguished from S. aglavei and S. fimbriatus (see table 4) by its dermal spines on its hind limbs that do not exceed 1 mm in length ( S. aglavei and S. fimbriatus spines exceed 1 mm, Glaw and Vences, 1997); absence of dermal spines with multiple points ( S. aglavei spines with multiple points); smaller SVL ( S. tavaratra SLV 30–36 mm, S. aglavei 40–51 mm, S. fimbriatus 36–39 mm); and tibio-tarsal extension that may extend beyond the nostrils ( S. aglavei and S. fimbriatus to nostrils). Spinomantis tavaratra can be distinguished from S. massorum by the shorter snout ( S. tavaratra NSD , 2 mm; S. massorum NSD. 2.1 mm); dark markings on venter and throat ( S. massorum lacks dark markings on venter and throat); a tibio-tarsal extension that may extend past the nostril ( S. massorum tibiotarsal extension reaches between the eye and nostril); and less developed webbing on toe 4 ( S. tavaratra 2 to 2.5:IV:2 to 2.5, S. massorum 0.75 to 2:IV:1 to 2).

TABLE 4 Morphometric data for Spinomantis aglavei , S. fimbriatus , and S. phantasticus . All measurements in mm. ZFMK specimen data from Glaw and Vences (1994, 1997).

DESCRIPTION OF HOLOTYPE: Adult male in a good state of preservation with vocal sac, distinct femoral gland, and mature testes measuring 3.6 X 0.9 mm, and whitish yellow in color. The skin, femoral gland, and muscle have been removed from the right thigh for a tissue sample.

Head laterally and dorsally with scattered weak tubercles. Head 1.19 times wider than long. Head length 0.33 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 0.26 times head width. Nostrils open laterally. Pupil round. Eye to nostril distance two times nostril to snout distance and 0.89 times eye diameter. Tympanum well defined, diameter 0.28 times eye diameter. Supratympanic ridge present and uniform, arching from posterior of eye to above the forelimb insertion point. Vomerine teeth present, vomerine bone triangular in shape.

Arms slender and smooth with forearm length 0.25 times SVL. No dermal spines on arms or body. Hand length (including disks) 0.37 times SVL with no webbing. Relative finger lengths 1, 2, 4, 3. Fingers and toes with enlarged triangular disks. Disk of third toe two times wider than terminal phalange. Dorsum and flanks smooth with a few rounded tubercles concentrated on the posterior dorsal region of the head and the posterior dorsal region of the body. Venter weakly granular.

Tibio-tarsal extension reaches between nostrils and snout tip. Thigh length 0.52 times SVL . Ventral surface of thigh granular, all other leg surfaces but with some scattered tubercles. Type 2 oval femoral glands differentiated and distended, measuring 5.5 X 1.8 mm. Approximately 40 granules with no central pore visible in external view. In internal view, 47 opaque granules, some with translucent perimeters. Lower leg 0.54 times SVL. Foot , including tarsus, 0.75 times SVL . Four simple dermal spines,,1.0 mm in length, approximately evenly spaced and increasing in size proximally on the posterior margin of the tarsus. Inner and outer metatarsal tubercles present, with round outer metatarsal tubercle 0.5 mm in diameter and elliptical inner metatarsal tubercle 1.8 mm in length. Relative toe lengths 1, 2, 5, 3, 4. Foot webbing: I 1 – 1.5 II 1 – 1.75 III 1.25 – 2.5 IV 2.5 – 1 V .

COLORATION IN PRESERVATIVE: Head dorsally and laterally reddish brown with scattered small brown spots, with larger dark brown spots concentrated on the canthus rostrum and supratympanic ridge, and a dark brown band between the eyes. Iris dark brown. Dorsum reddish brown with darker brown spots. Flanks yellowish white with faint brown spots. Arms with two dorsal broken grayish-brown transverse stripes. Legs with nine broken grayish-brown transverse stripes of uneven width. When in sitting posture, dorsal stripes on the hind limbs line up, forming three longitudinal stripes. Ventral arms and legs yellowish white with brown small spots. Throat yellowish white with lower lip bordered by grayish-brown spots. Venter yellowish white with scattered fine dark brown spots on the chest. Femoral glands brown in external view and white in internal view.

COLORATION IN LIFE: Some of the reddishbrown pigment on the dorsal surface of the head and body is pale green in life. The flanks are silvery white with pale yellowish-green fine spots. The tarsal spines are white. The iris is silvery white, with dark brown radiating bands, and a pale blue iris ring.

VARIATION: Morphometric variation is summarized in table 3. All specimens agree with the holotype description with the following exceptions. The presence of tubercles on the dorsum, head, and flanks range from being sparsely dispersed, as in AMNH A167934 , to frequent, as in UMMZ 212366 . The supratympanic ridge is reduced and broken in AMNH A157070–71 , A157073 , and UMMZ 212368 . The tibio- tarsal exten- sion may extend beyond the snout tip ( AMNH A157070 , A157072 ; UMMZ 212366– 67 ). Simple dermal spines may be present on the posterior surface of the forearm (table 3). Dermal spines on the hind limb range from approximately uniform in spacing and size, as in the holotype, to alternating in size, with dermal spines generally reduced in size distally. Femoral glands 4.1–7.2 mm in length and 1.8–3.1 mm in width, separated by 2.4 to 3.5 mm, with approximately 20 to 40 granules visible in external view. Inner metatarsal tubercle range from 1.0 to 1.8 mm in length. Foot webbing variation: I 0.5 to 1 – 0.75 to1.5 II 0 to 1 – 0.5 to 2 III 0.5 to 1.25 – 2 to 2.5 IV 2 to 2.75 – 0.75 to 1 V .

Females AMNH A157070, A157072–73, A167933, and A167936–37 lack femoral glands. AMNH A167933 is a gravid female with at least 25 visible eggs (up to 2.4 mm diameter) seen in ventral internal view. Juveniles AMNH A157069 and UMMZ 212364 lack femoral glands, but have fore- and hind limb dermal spines present similar in number and placement to those of adults.

UMMZ 212364 has very fine brown spotting on the venter. AMNH A167933 has silver-colored longitudinal stripes on the canthus rostrum, between the eyes, and dorsolaterally on the body. The dorsum dark brown blotches and spots loosely define a postocular ‘‘W’’ in UMMZ 212366–67. The dark spotting on the venter may extend to the throat (AMNH A167933 and A167936).

ETYMOLOGY: The specific name tavaratra refers to the Malagasy word for ‘‘the north’’. This name is used as a nonlatinized specific epithet, and is given in reference to the known distribution of this species in northern Madagascar.

DISTRIBUTION: Known only from humid forests in NE Madagascar, between 650– 1300 m elevation. Most specimens have been collected from the Marojejy Massif (including the Betaolana corridor), but the species is known to occur as far north as the Sorata Massif.

REMARKS: All specimens were collected at night, between 1800 and 2300 hours, in areas by the edges of rivers and small fast-flowing streams. Animals were found on leaves, branches, and tree trunks, at heights of 0.8– 4.0 m above the forest floor.

Glaw and Vences (1997) report on four male specimens (ZFNK 59900, 59926–28) from 700 m elevation at Marojejy that may represent additional S. tavaratra material based on their SVL of 31–34 mm. Although these authors attributed these specimens to S. fimbriatus (type locality Andasibe, 500 km south of Marojejy), they also noted the small body size and differences in the call of these Marojejy specimens compared to the Andasibe S. fimbriatus .

Figures

Fig. 1. Photos of selected live Spinomantis species. A. Spinomantis brunae, UMMZ 198405, Ampamakiesiny Pass (photo: C.J. Raxworthy). B. S. brunae, UMMZ 198407, Ampamakiesiny Pass (photo: C.J. Raxworthy). C. S. massorum, UMMZ 212362, Antsahabe River, Manongarivo Special Reserve (photo: C.J. Raxworthy). D. S. massorum, AMNH A167941, Ramena River, Tsaratanana Strict Nature Reserve (photo: C.J. Raxworthy). E. S. tavaratra, new species, AMNH A167937, Sorata Mountain (photo: C.J. Raxworthy). F. S. aglavei, UMMZ 212374, Andringitra Strict Nature Reserve (photo: C.J. Raxworthy).

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

Fig. 3. Spinomantis massorum and S. tavaratra, new species. A. Dorsal views of S. massorum (above, left to right): AMNH A167944, 167938, UMMZ 212359; and S. tavaratra, new species (below, left to right): AMNH A167935, 167933, 167936. B. Ventral views of S. massorum (above, left to right): AMNH A167944, 167938; and S. tavaratra, new species (below, left to right): AMNH A167935, 167933.