Madascincus miafina, Miralles, Aurelien, Koehler, Joern, Glaw, Frank & Vences, Miguel, 2016

Miralles, Aurelien, Koehler, Joern, Glaw, Frank & Vences, Miguel, 2016, Species delimitation methods put into taxonomic practice: two new Madascincus species formerly allocated to historical species names (Squamata, Scincidae), Zoosystematics and Evolution 92 (2), pp. 257-275 : 259-264

Madascincus miafina sp. n. Figs 3B, 4J, K

Holotype.

ZSM 1562/2008 (FGZC 1658), adult male, from near Petit Tsingy, 12°57 ’25’’ S, 49°07 ’06’’ E, 90 m above sea level, Ankarana Special Reserve, Antsiranana province, north Madagascar, collected on 16 February 2008 by M. Franzen, F. Glaw, J. Köhler and Z. Nagy.

Paratypes

(n=23, all from Antsiranana province, northern Madagascar). ZSM 242/2004 (FGZC 474), 245/2004 (FGZC 480), Montagne des Français, 12°19 ’34’’ S, 49°20 ’09’’ E, 334 m a.s.l., coll. on 23 and 24 February 2004 by F. Glaw, M. Puente and R.D. Randrianiaina; UADBA uncatalogued (FGZC, 1788, 1789), Montagne des Français, coll. by Frontier staff at unknown date; ZSM 1571/2008 (FGZC 1766), 1572/2008 (FGZC 1844), Baie des Sakalava (ca. 5 km SE Ramena), 12°16.371'S, 49°23.338'E, 28 m a.s.l., coll. on 22 and 26 February 2008 by S. Megson; ZSM 1573-1577/2008 (FGZC 1678, 1680, 1687, 1836, 1838), UADBA uncatalogued (FGZC 0481, 1677, 1684, 1762, 1763, 1835), Montagne des Français (pitfall lines 1, 2 & 5, no coordinates available), coll. on 19 and 25 February 2008 by N. D’Cruze and local collectors; ZSM 259/2004, Montagne des Français, coll. on 18-28 February 2004 by F. Glaw, M. Puente, R.D. Randrianiaina and A. Razafimanantsoa; ZSM 1570/2008 (FGZC 1917), Ampombofofo region, 12°05.571'S, 49°19.035'E (trapsite 5), coll. on 23 February 2007 by S. Megson; ZSM 1563/2008 (FGZC 1827), same data as holotype, but collected by a local assistant on 24 February 2008; UADBA uncatalogued (FGZC 1742, 1768, 1840), Orangea, coll. in February 2008 by S. Megson.

Other specimens examined.

(n=2, not sequenced). MNHN 1897.31, Diego Suarez; MNHN 1980.1169, Bemanevika, Plateau Bealanana.

Chresonyms.

Scelotes intermedius - Brygoo (1981, partim);

Amphiglossus intermedius - Brygoo (1984, partim);

Madascincus intermedius - Glaw and Vences (2007, partim);

Madascincus polleni "clade 1 ”– Miralles et al. (2011b);

Madascincus polleni " polleni -N clade" - Miralles and Vences (2013);

Madascincus sp. " polleni " northern clade - Miralles et al. (2015).

Diagnosis.

A member of the genus Madascincus based on its molecular phylogenetic relationships (see Fig. 1). Within the genus Madascincus , Madascincus miafina is distinguishable from all its congeners by the following combination of characters: medium body size with a maximum snout-vent length (SVL) of 61.0 mm (versus, in smaller species, a maximum SVL of 33.6 mm in Madascincus nanus complex, 47.4 mm in Madascincus minutus , 50.5 mm in Madascincus ankodabensis , 53.5 mm in Madascincus melanopleura ); 65-79 rows of paravertebral scales (versus 51-62 in Madascincus melanopleura , 57-65 in Madascincus minutus , 52-62 in Madascincus ankodabensis , 60-65 in Madascincus mouroundavae , and 50-57 in Madascincus nanus complex); 65-73 rows of ventral scales (versus 55-63 in Madascincus minutus , 56-61 in Madascincus melanopleura , 52-60 in Madascincus nanus complex, 59-63 in Madascincus ankodabensis , 63-66 in Madascincus mouroundavae , 73-78 in Madascincus pyrurus , 74-78 in Madascincus polleni and 75-80 in Madascincus arenicola ); 18-23 subdigital lamellae under the fourth toes (versus 5-8 in Madascincus nanus complex, 9-13 in Madascincus minutus , 12-15 in Madascincus ankodabensis , 12-16 in Madascincus melanopleura and 15-18 in Madascincus pyrurus ); 24-26 rows of scales around midbody (versus in Madascincus nanus complex, 28-30 in Madascincus mouroundavae , 22-24 in Madascincus pyrurus and 30-32 in Madascincus stumpffi ); pentadactyl forelimbs (versus 3-5 digits in Madascincus nanus complex); and most often (89.3%) the presence of postnasal scales (always absent in Madascincus arenicola ). The frontal is bell-shaped (versus hourglass-shaped in Madascincus nanus , Madascincus minutus , Madascincus melanopleura , Madascincus ankodabensis , Madascincus mouroundavae , and in half (52.8%) of the specimens examined of Madascincus stumpffi ); the frontal is always separated from the interparietal (versus most often (87.5%) fused in Madascincus mouroundavae ). The lower eyelid window is scaly (versus spectacled in Madascincus igneocaudatus , Madascincus pyrurus , Madascincus minutus , Madascincus melanopleura and Madascincus ankodabensis ); absence in most specimens (92.3%) of a single row of enlarged nuchal scales (versus presence of at least two rows in Madascincus igneocaudatus , Madascincus pyrurus and Madascincus minutus ). More generally, Madascincus miafina can be distinguished from all the other species (with exception of Madascincus polleni ) by its apparently very conserved pattern of coloration, characterized by a single pair of lateral dark brown stripes relatively large and well-defined anteriorly, then progressively breaking up into two parallel very thin dashed lines posteriorly to forelimbs, hardly distinguishable from the rest of the dots covering the body.

Madascincus miafina differs from its sister species Madascincus arenicola by a paler coloration, with lateral lines well defined anteriorly, becoming one - or two parallel - very thin dashed line posteriorly to forelimbs (versus a very contrasted coloration in Madascincus arenicola , characterized by the presence of a pair of two-scale wide dark lateral lines extending from snout to hindlimbs, well defined all along the body) and by a relatively shorter snout, rounded in lateral aspect (versus a relatively long snout, acute in lateral aspect, in Madascincus arenicola ). It also differs by a lower number of ventral scales (65-73 vs. 75-80 in Madascincus arenicola ). Moreover, Madascincus miafina is one of the few species (together with Madascincus pyrurus and Madascincus igneocaudatus ) in which the tail might be bright red in some specimens (see also Tables 1 and 2). Morphologically, the species most similar to Madascincus miafina is Madascincus polleni (including its junior synonym Madascincus intermedius ); this species is identical in coloration, body shape, and body size to Madascincus miafina despite not being the direct sister species, differing only by the number of ventrals (see above).

Description of the holotype

(Fig. 3B). ZSM 1562/2008 (FGZC 1658). Adult male, with both hemipenes everted. Good state of preservation, with exception of a little circular sampling incision on the left flank (ca. 5 mm of diameter). SVL (57.0 mm) 7.5 times head length (7.6 mm), almost as long as tail (79.1 mm, apparently entire and not regenerated). Limbs relatively short: SVL 5.6-5.8 times front limb length (9.9-10.2 mm) and 3.2-3.3 times hind limb length (17.3-18.0 mm). Snout relatively short and rounded on lateral aspect, with a rostral tip bluntly rounded in dorsal aspect. Rostral wider than high/long, contacting first supralabials, nasals, and supranasals. Paired supranasals in median contact, contacting loreals. Frontonasal roughly triangular, wider than long, contacting loreals, first supraciliaries and first suproculars. Prefrontals absent. Frontal approximately as wide as long, wider posteriorly, in contact with frontonasal, supraoculars, parietals and interparietal. Supraoculars four, all of them in contact with frontal; subequal in size, except for the posteriormost pair that is significantly smaller; the first pair not constricting frontal (frontal bell-shaped sensu Andreone and Greer 2002). Frontoparietals absent. Interparietal longer than wide, well separated from supraoculars; parietal eyespot present with parietal eye evident. Parietals contact posterior to interparietal. Absence of enlarged nuchals. Nasals just slightly larger than nostrils; contacting rostral, first supralabials, postnasals and supranasals. Postnasals present, separating supranasals from first supralabials, and nasals from loreals. Loreal single, slightly higher than long. Preocular trapezoidal, longer than high, single. Presubocular roughly square, single. Six supraciliaries on both sides, in continuous row; first and last pairs significantly larger and longer than the intermediate ones; last pair projecting onto supraocular shelf. Upper palpebrals small except for last which projects dorsomedially. Pretemporals two, both contacted by parietal. Postsuboculars two; upper contacting lower pretemporal; both contacting penultimate supralabial. Lower eyelid moveable, scaly; lower palpebrals small, longer than high, interdigitating with large polygonal scales of central eyelid. Contact between upper palpebrals and supraciliaries seemingly direct but flexible, i.e. palpebral cleft narrow. Primary temporal single. Secondary temporals two; upper long, contacting lower pretemporal anteriorly and overlapping lower secondary temporal ventrally. Two tertiary temporals bordering lower secondary temporal. Supralabials six, with the fourth being the enlarged subocular, contacting scales of the lower eyelid. Postsupralabial single. External ear opening round, without lobules. Mental wider than long, posterior margin convex. Postmental wider than long, contacting first two pairs of infralabials. Infralabials six. Three pairs of large chin scales, both members of first pair in contact, both members of second pair separated by a single median scale, and 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 the third pair of chin scales. Gulars similar in size and outline to ventrals. All scales, except head shields and scales on palms, soles, and digits, cycloid, smooth, and imbricate; longitudinal scale rows at midbody 24; paravertebrals 68, similar in size to adjacent scales; ventrals 68. Inner preanals overlapped by outer. Both pairs of limbs pentadactyl; fingers and toes relatively short, clawed; relative length of toes in the following order: I<II<V<III<IV. Subdigital lamellae smooth, single, with 8 under right fourth finger and 7 under left fourth finger, 18 under right fourth toe, and 20 under left fourth toe.

Coloration of the holotype in preservative with a pair of lateral dark brown stripes (about two scales wide on the neck) relatively large and well defined anteriorly (overlapping rostral, mental, first four supralabials, loreals, and presuboculars), then progressively breaking up into two parallel very thin dashed lines posteriorly to forelimbs, hardly distinguishable from the rest of the dots covering the body. Dorsum and dorsal sides of forelimbs, hindlimbs and tail light bronze. The bronze dorsal field and flanks are covered by numerous little dark dots, each of them in the middle of a dorsal scale, in contact with its posterior edge; resulting in many thin dash lines (14 to 16 at midbody, including the dark lateral stripes), darker and more contrasted in the posterior part of the dorsum, then posteriorly becoming progressively indistinguishable from the background coloration of tail, and laterally, becoming progressively indistinguishable from the light coloration of the ventral field. No distinct border between the background coloration of the dorsal and the ventral sides. Immaculate whitish ventral field extending from lower side of head (mental excluded), throat, lower side of limbs and venter, to the ventral side of tail. Palms and soles barely darker than venter. Coloration in life was almost identical to the coloration in preservative, with the only significant difference being the presence of iridescent glints of scales and a venter with some violet-pinkish tint (cf. Figs 4J, K).

Variation.

For variation in measurements and scale characters see Table 1. Some variation is evident with respect to overall dorsal and tail coloration. The paratype from Ankarana was more or less similar to the holotype described above, with a bronze dorsal color predominating the dorsum and tail. At Montagne des Français, specimens were generally darker, with a bronze-brown dorsal coloration and a reddish brown tail dorsally and red-orange tail ventrally.

Etymology.

The specific epithet miafina is the Malagasy word for “secretive”. The name refers to the secretive habits of the species, as all specimens were exclusively trapped by pitfalls and never observed in situ, as well as to the fact that this species was hidden behind several other taxon names in use and could only be discovered by an integrative taxonomic approach. The name is treated as an invariable noun in apposition.

Distribution, habitat and habits.

The species is known from northernmost Madagascar including at least four localities (see localities of type specimens above and Fig. 5) with karstic outcrops and sandy soils. The species apparently has nocturnal and secretive habits, as all specimens were exclusively caught by pitfall trapping overnight in forest or shrub areas. The species can therefore be considered to represent a leaf litter dweller. The new species occurs in sympatry with Madascincus arenicola and Madascincus stumpffi . Hence, it appears to tolerate a rather wide range of habitat conditions, whereas Madascincus arenicola exclusively occurs on sandy soils and Madascincus stumpffi seems to be restricted to forests. Nothing else is known on the natural history of the new species.