Paracontias vermisaurus, Vieites Frank Glaw Miguel Vences, 2011

Vieites Frank Glaw Miguel Vences, Aurélien Miralles Jörn Köhler David R., 2011, Hypotheses on rostral shield evolution in fossorial lizards derived from the phylogenetic position of a new species of Paracontias (Squamata, Scincidae), Organisms Diversity & Evolution (New York, N. Y.) 11 (2), pp. 135-150 : 141-143

Paracontias vermisaurus sp. n.

( Figures 3 and 4a )

Etymology The specific epithet is derived from the Latin vermis (worm) to the Greek sauros (lizard); it is to be treated as a noun in apposition for the purposes of nomenclature.

Type material Holotype ( ZSM 597 /2008; field number ZCMV 11211 ), apparently an adult specimen; northeastern Madagascar, Makira Reserve , site locally named Angozongahy, 15°26′13.3″ S, 49°07′07.0″ E, 1,009 m a.s.l., collected 20–22 June 2009 by C. Patton, J. Patton, E. Rajeriarison, T. Rajoafiarison, R. D. Randrianiaina, F. Ratsoavina ,, M. Vences and D. R. Vieites . Paratype ( ZSM 598 /2008; field number DRV 5935 ), adult ; data as for holotype, except site locally named Ampofoko, 15°25′22.3″ S, 49°07′15.1″ E, 1,034 m a.s.l., 28 June 2009 .

Diagnosis Small brownish apodous scincine species in Paracontias Mocquard , as revealed by sequence analyses of mitochondrial and nuclear genes as well as by the absence of legs, supranasals and postnasals, the main morphological synapomorphies that in combination differendivergences (uncorrected p-distances, shown as percen-

tages) in the genus Paracontias ;

below table diagonal: most conservative gene (phosducin),

mean interspecific distance =

1.6±0.7, range = 0.3 to 2.7;

above diagonal: most divergent gene (ND1), mean interspecific distance = 14.3±0.02, range =

8.7 to 18.3

tiate the genus from other Malagasy scincines, including from limbless species assigned to Amphiglossus .

Paracontias vermisaurus sp. n. differs from congeneric species by the following combination of character states: presence of loreals separated from each other by the rostral to the frontonasal (versus very large loreals extending and meeting each other at dorsal midline in P. kankana , loreals absent in P. milloti ); two supralabials between the rostral and the subocular supralabial (three in Amphiglossus stylus ; one in P. hildebrandti ), hourglass-shaped frontal (bell-shaped in P. brocchii , P. kankana , P. manify , P. minimus , P. rothschildi , P. tsararano ); 20 scale rows around midbody (16 in P. rothschildi and P. fasika ; 18 in P. milloti and P. minimus ; 21 in P. kankana and P. tsararano ; 22 in P. manify ; 26 in P. brocchii ; 31 in P. holomelas ); nostril in contact with first supralabial (nostril deeply within rostral and posteriorly connected by distinct narrow join with first supralabial in P. hafa , P. hildebrandti , P. holomelas , P. minimus , P. manify and P. tsararano ); three supraoculars largely in contact with the frontal (two in P. brocchii , P. milloti , P. kankana , P. tsararano , P. rothschildi ; one in P. minimus ), eye opening not covered by scales (eye sunken below ocular scale in P. minimus ); a uniform dark coloration (bicolored pattern with lighter wide mediodorsal stripe in P. fasika and P. rothschildi ). Additionally, P. vermisaurus differs from the morphologically similar P. hafa in having a relatively larger eye with a prominent supraocular region (versus a flat, laterally depressed supraocular region), and by brownish live coloration with a faint violet tint (versus pale with pinkish tint).

Description of holotype In good state of preservation, except for the tail that has been autotomised 8 mm posterior to the cloaca. Unsexed, apparently adult specimen. Snout-to-vent length 53.8 mm, width at midbody 3.5 mm, head width at level of parietal eye 3.6 mm.

In general appearance, a brown skink of relatively small size, slender, with both pairs of limbs completely absent. Snout blunty rounded in both dorsal and lateral aspect, with a rostral tip blunty rounded in dorsal aspect. Rostral wider than long, contacting first supralabial, loreal and frontonasal. Supranasals absent, apparently fused with rostral. Frontonasal roughly trapezoidal, wider than long, contacting loreals, first supraciliaries and first suproculars. Prefrontals absent. Frontal approximately as wide as long, wider posteriorly, in contact with frontonasal, first three supraoculars, parietals and interparietal. Supraoculars four, the second and third pairs longer in size, the posteriormost pair significantly smaller. Frontoparietals absent. Interparietal triangular, longer than wide, well separated from supraoculars; parietal eyespot present, with parietal eye evident. Parietals contact each other posterior to interparietal. Parietal in contact with two pairs of cycloid dorsal scales; enlarged nuchals absent. Nasal only slightly larger than nostril, contacting rostral and first supralabials. Postnasals absent, apparently fused with rostral. Loreal single, about as high as long. Preocular wider dorsally than ventrally, single. Presubocular lozenge-shaped, single. Five supraciliaries on either side, in continuous row; first, second and last pairs significantly larger and longer than intermediate ones; last pair projecting onto supraocular shelf. Upper palpebrals small, except for last which projects dorsomedially. Pretemporals two, the upper contacting the parietal, the lower the primary temporal scales, both contacting upper secondary temporal. Postsuboculars single, contacting penultimate supralabial, primary temporal and lower pretemporal. Lower eyelid moveable, scaly; five rectangular lower palpebrals in contact with eye, the last being the largest. Contact between upper palpebrals and supraciliaries apparently direct but flexible, i.e. palpebral cleft narrow. Primary temporal single. Secondary temporals two; the upper long, broadly contacting the upper and barely the lower pretemporals anteriorly. Two tertiary temporals bordering lower secondary temporal. Supralabials five, the third being the enlarged subocular contacting scales of lower eyelid. Postsupralabial single. External ear opening absent, with no indication of its former position. Mental wider than long, posterior margin straight. Postmental pentagonal diamond-shaped, wider than long, contacting first pair of infralabials. Infralabials four. Three pairs of large chin scales; members of first pair in contact behind postmental, members of second pair separated by a single median scale row, members of third pair separated by three scale rows. No scales extending between infralabials and large chin scales; two asymmetrical postgenials posterolaterally in contact with third pair of chin scales. Gulars similar to ventrals in size and outline. All scales except head shields cycloid, smooth and imbricate. Longitudinal scale rows on flanks disrupted at level of two weak lateral depressions with reduced scales, indicating former position of forelimbs. Longitudinal scale rows at midbody 20; paravertebrals 109, similar in size to adjacent scales; ventrals 103. Inner preanals larger and longer than outer ones.

For live coloration, see Fig. 4a . In preservative, ground coloration dark brown; head immaculate dark brown, rostral, first supralabial and mental scales with milky slightly paler color, supraoculars darker than other supracephalic scales; parietal eyespot visible as beige spot; lower eyelid whitish, with upper part bordering the eye dark brown; dorsal body scales brown with dark brown color at their posterior and pale beige at their lateral edges; numerous minute irregular beige flecks and spots present within scales; tail base (posterior tail amputated) slightly darker than rest of body; from throat to cloaca, flanks slightly paler than dorsal scales due to spreading of pale coloration within each ventral scale row.

Variation The only other known specimen, the paratype, is slightly larger than the holotype: snout-to-vent length 60.5 mm, width at midbody 4.5 mm, head width at level of parietal eye 4.3 mm. Cephalic scalation identical to holotype; longitudinal scale rows at midbody 20; paravertebrals 105, ventrals 98. Coloration in preservative identical to holotype.

Distribution and natural history Only known from two sites in the primary rainforest of Makira reserve located close to each other, both close (<50 m) to streams and around 1,000 m a.s.l. ( Fig. 5 ). The rainforest is somewhat degraded at both sites; at Ampofoko (the paratype locality) multiple traces of cattle were found. The holotype was captured in a pitfall line (10 l buckets in the ground at 10 m distances, connected by a plastic barrier of a total length of 50 m); the paratype was found by field assistants while actively searching under rotten logs and leaf litter.

Figures

Fig. 3 Head of Paracontias vermisaurus sp. n. (holotype, ZSM 597/2008). a Dorsal view. b Ventral view. c Lateral view

Fig. 4 Live habitus of holotypes of Paracontias vermisaurus sp. n. a and P. hafa b. Photographs by M. Vences and F. Andreone, respectively

Fig. 5 Rainforest at Makira Reserve (>1,000 m a.s.l.). a General view. b At the collecting locality of the paratype, a site locally named Ampofoko