Sphaerodactylus guanajae, Mccranie, James R. & Hedges, Blair, 2012

Mccranie, James R. & Hedges, Blair, 2012, Two new species of geckos from Honduras and resurrection of Sphaerodactylus continentalis Werner from the synonymy of Sphaerodactylus millepunctatus Hallowell (Reptilia, Squamata, Gekkonoidea, Sphaerodactylidae), Zootaxa 3492, pp. 65-76 : 70-72

Sphaerodactylus guanajae sp. nov.

( Fig. 4 )

Sphaerodactylus continentalis — Meyer & Wilson, 1973:12 (part). Sphaerodactylus continentalis — Wilson & Hahn, 1973:105 (part). Sphaerodactylus millepunctatus — Harris & Kluge, 1984:17 (part). Sphaerodactylus millepunctatus — McCranie et al., 2005:80 (part). Sphaerodactylus millepunctatus — McCranie et al., 2006:110 (part).

Holotype. USNM 580000, an adult male from East End, 16.486°, -85.832°, Isla de Guanaja, Islas de la Bahía, Honduras, near sea level, collected 16 November 2011 by James R. McCranie.

Paratypes (6). USNM 579994–95, 579996 (genetic sample 1, JX 073112 , JX 073123 ), 579997 (genetic sample 2, JX 073113 , JX 073124 ), 579998–99, same data as holotype, except 16–17 November 2011; all adult females except USNM 579997 is a juvenile. Appendix II lists additional specimens of this new species.

Geographic distribution. Sphaerodactylus guanajae is known to occur at low elevations on Isla de Guanaja in the Islas de la Bahía, Honduras. The species is known only from three nearby localities on the northeastern end of the island ( Fig. 3 ).

Diagnosis. Sphaerodactylus guanajae can be distinguished from S. millepunctatus (sensu stricto), the species it was previously identified as, and from S. continentalis , herein removed from the synonymy of S. millepunctatus , in having a short pale longitudinal line located above each pelvic area that curves inward posteriorly to almost always connect with its counterpart on the other side, dark dorsal spots on the body occupying single scales, and dark lines on the head and body indistinct (versus short pale pelvic line absent, dark dorsal spots on body occupying more than one scale, and dark lines usually distinct on posterior portion of head and anterior portion of body in S. millepunctatus and S. continentalis ). Sphaerodactylus guanajae also differs from S. continentalis and S. millepunctatus in having fewer subdigital lamellae on the fourth digit of the hind limb (8–9, x = 8.6 ± 0.5 on 12 sides in S. guanajae versus 9–12, x = 10.0 ± 0.8 on 40 sides in S. continentalis and 9–12, x = 9.7 ± 0.8 on 30 sides in S. millepunctatus ). Sphaerodactylus guanajae differs from S. leonardovaldesi in having fewer subdigital lamellae under the fourth toes and fourth fingers (8–9, x = 8.6 ± 0.5 and 7–8, x = 7.6 ± 0.5 on 12 sides, respectively, and 31–34, x = 32.3 ± 1.5 combined subdigital lamellae on fourth digits in S. guanajae versus 9–12, x = 10.2 ± 0.8 and 8–10, x = 9.0 ± 0.4 on 26 sides, respectively, and 36–42, x = 38.5 ± 1.6 combined subdigital lamellae on fourth digits in S. leonardovaldesi ) and in usually having the pelvic lines dorsally crossing the base of the tail to connect (in 5 of the 6 adults [narrowly separated in one adult] and in the juvenile) with their counterparts on the other side (versus pelvic stripes widely separated from their counterparts on other side in S. leonardovaldesi ). Sphaerodactylus guanajae occurs sympatrically with one other species of Sphaerodactylus , S. rosaurae Parker , but is most easily distinguished from that species in having all dorsal body scales of a similar size (versus middorsal row of granular scales that are sharply and distinctly differentiated from the much larger surrounding dorsal scales in S. rosaurae ). Sphaerodactylus guanajae also differs from S. continentalis , S. leonardovaldesi , and S. millepunctatus in an amount of cytochrome b DNA sequence divergence (6.8–10.1 %; Fig. 1 ) comparable to that seen among other species of lizards ( Johns & Avise 1998; Hedges & Conn 2012).

Description of holotype. A moderate-sized Sphaerodactylus with a snout-vent length (SVL) of 26.2 mm; snout-ear length (head length) 5.9 mm; head width 2.5 mm; head depth 2.2 mm; snout length 3.0 mm, snout length/ eye-ear length 1.30; tail length 23.2 mm (partially regenerated), tail length/SVL 0.89.

Rostral with long median cleft and short posterior notch occupied by a single small scale; supranasals two, anterior one largest, rounded, dorsally confined, in contact with nasal opening, separated from first supralabial by posterior supranasal and two small postnasals, anterior supranasal contacting rostral above nasal opening; internasals three, occupying space wider than greatest width of anterior supranasal; snout scales swollen, keeled, juxtaposed, 9 along midline from orbits to rostral, four per interorbital width (IOW); scales between eyes narrower than snout scales; parietal surfaces and nape covered with swollen keeled granules, about 5–6 per IOW; superciliary spine short, located at level anterior to mideye; fourth supralabial lies below anterior half of eye, shorter fifth supralabial lies below center and posterior portion of eye; third infralabial lies below anterior half of eye, fourth infralabial lies below posterior half of eye, first infralabial largest, its length equals nearly 2.0 times IOW; mental large, about as long as wide, with oblique sutures between infralabials; postmentals two, polygonal, not elongated; gular scales smooth, granular, juxtaposed, five per IOW.

Dorsal scales of trunk oval, flattened, keeled, imbricate, about four per IOW, 57 along midline between levels of axilla and groin; lateral scales similar to dorsals; ventrals smooth, flat, about two per IOW, 33 along midline between levels of axilla and groin; scales around midbody 63; escutcheon somewhat bell-shaped, with lateral extension ca. 10 scales wide on subfemoral surface, escutcheon also extending slightly onto groin region; supracaudal scales rhomboid, flat, imbricate, keeled at base of tail to about point reached by extended hind limb, smooth distal to that point, about two per IOW; subcaudal scales smooth, larger than supracaudals, scales of median series largest, slightly widened, enlarged median series extending about two-thirds length of tail; pair of distinctly swollen granules at each corner of vent; subdigital lamellae smooth, 8–9 present on fourth toe, 7–7 present on fourth finger, 31 combined subdigital lamellae on fourth digits.

Color in life: dorsal surface of body Brussels Brown (121B) with pale brown mottling and scattered Sepia (119) scales; dirty white pelvic stripe extending posteriorly from level above groin to base of tail where it crosses dorsal surface of tail to connect with similarly colored stripe on other side of tail and body; dorsal and lateral surfaces of head Sayal Brown (223C) with scattered Sepia scales forming indication of lines; dorsal surfaces of limbs Brussels Brown with pale brown bands on lower parts of limbs and on all digits; dorsal surface of unregenerated portion of tail Sayal Brown with scattered Sepia scales and pale brown indications of cross lines; dorsal surface of regenerated portion of tail Cinnamon (39); chin pale brown; throat cream; belly pale brown with dark brown flecking; subcaudal surface of original portion of tail Flesh Ocher (132D).

Color in alcohol: dorsal surface of body brown without distinctive markings; dorsal surface of head pale brown with faint dark brown line on snout and posterior to eye, latter line extending to about shoulder region; supraocular scales dark brown; dorsal surfaces of limbs and tail similar to that of dorsal surface of body, but with pale brown dorsal spot on knee and pale brown dorsal band on shank; supralabials pale brown with dark brown flecking; ventral surface of head cream with brown flecking; belly pale brown with brown flecking on scale edges; subcaudal surface cream with brown flecking on scale edges, forming incomplete lineate pattern; distinct ventrolateral cream stripe extending from base of tail onto posterior surface of thighs; pelvic line distinct, pale brown, crossing dorsally on base of tail to connect with counterpart on other side.

Variation. The six adults in the type series have a SVL of 24.4–26.2 (25.6 ± 0.7) mm, 57–66 (61.3 ± 3.3) dorsal scales, 32–35 (33.5 ± 1.2) ventral scales, 60–70 (64.4 ± 3.8, n = 5) scales around midbody, 9–13 (11.0 ± 1.4) snout scales, 8–9 (8.6 ± 0.5) subdigital lamellae on the fourth toe, 7–8 (7.6 ± 0.5) subdigital lamellae on the fourth finger, 31–34 (32.3 ± 1.5) combined subdigital lamellae on fourth digits, and all have the short pale lines above the pelvic region visible in preservative, with 5 of the 6 having those lines connected with their counterparts on the other side (the single exception [USNM 579996] has those two pale lines only narrowly interrupted medially by brown). Otherwise, all six adults are similar to the holotype in coloration. The juvenile has a brown lined pattern on the head and much of the body. One adult paratype (USNM 579994) was similar in color in life to that of the holotype, except that the subcaudal surface was yellowish brown.

Habitat. The type series was found only in association with Sea Grape ( Cocoloba uvifera ) leaf litter. Two were active during the morning on top of the leaves and the others were found by raking through the leaf litter. Efforts to find specimens under other types of ground debris on Guanaja at that time were unsuccessful.

Etymology. The specific name guanajae is formed from Guanaja and the Latin suffix –ae (used herein as a derivation), and alludes to this species occurring on Isla de Guanaja. The name is a feminine genitive singular noun.

Figures

FIGURE 1. Phylogenetic tree of four species of Middle American Sphaerodactylus from a maximum-likelihood analysis of DNA sequences of two mitochondrial genes (12 S rRNA and cytochrome b). A scale bar is indicated below. The numbers at nodes are bootstrap (left) and Bayesian (right) support values. The tree is rooted with the Middle American species S. dunni (not shown, for better visualization of ingroup).

FIGURE 3. Map of Honduras showing localities for specimens examined of Sphaerodactylus continentalis (circles), S. guanajae (inverted triangles), S. leonardovaldesi (squares), and S. millepunctatus (triangles).

FIGURE 4. Adult male holotype of Sphaerodactylus guanajae sp. nov. (SVL 26.2 mm). Photograph by J. R. McCranie.