Lygodactylus roellae, Vences & Multzsch & Gippner & Miralles & Crottini & Gehring & Rakotoarison & Ratsoavina & Glaw & Scherz, 2022

Vences, Miguel, Multzsch, Malte, Gippner, Sven, Miralles, Aurélien, Crottini, Angelica, Gehring, Philip-Sebastian, Rakotoarison, Andolalao, Ratsoavina, Fanomezana M., Glaw, Frank & Scherz, Mark D., 2022, Integrative revision of the Lygodactylus madagascariensis group reveals an unexpected diversity of little brown geckos in Madagascar’s rainforest, Zootaxa 5179 (1), pp. 1-61 : 29-38

Lygodactylus roellae sp. nov.

Lygodactylus sp. 17: Gippner et al. (2021).

Holotype. ZSM 49 /2016 ( MSZC 0072 ), adult female, collected by M.D. Scherz, J. Borrell, L. Ball, T. Starnes, E. Razafimandimby, D.H. Nomenjanahary, and J. Rabearivony at Ampotsidy mountains , 15.7 km NNW of Bealanana (8.7 km NNW of Beandrarezona), northern Madagascar, at geographical coordinates S14.41974, E48.71935, 1344 m a.s.l., on 22 December 2015 ( Fig. 15 ).

Paratypes. ZSM 556 /2014 ( DRV 6289 ), adult male, collected by F.M. Ratsoavina, D. Vieites, M. Vences, R. D. Randrianiaina, S. Rasamison, A. Rakotoarison, E. Rajeriarison, and T. Rajoafiarison at Andrevorevo, a site south of the Tsaratanana Massif, northern Madagascar, at geographical coordinates S14.3464, E49.1028, 1717 m a.s.l., on 21 June 2010 ; UADBA-R 70855 ( MSZC 0010 ), adult female, with the same collection data as the holotype but collected at S14.41878 E48.71896, 1354 m a.s.l. on 18 December 2015 at 20h20 .

Diagnosis. Lygodactylus roellae sp. nov. corresponds to a genetically highly distinct lineage from northern Madagascar that is the sister species of L. salvi described above, but differs by high genetic divergence and several scale counts. It belongs to subclade A3 within Domerguella as defined herein. It can also be assigned to the subgenus Domerguella by an undivided mental scale with two postmentals, absence of a claw on the first finger, and 5 preanal pores in males. Within Domerguella , the new species is only known from two localities in northern Madagascar and differs from the other nominal species of Domerguella occurring in this part of the island as follows: from L. expectatus by a different color pattern, without scapular semi-ocellus and with a striped pattern apparently in most individuals (vs. scapular semi-ocellus usually present, and striped pattern unknown); from L. rarus by lack of regular crossbands on tail (vs. presence) and different body shape without elongated limbs (relative hindlimb length 0.41–0.45 vs.>0.55); from L. madagascariensis , L. petteri , L. salvi , and L. tantsaha by smaller longitudinal dorsal scale count (159–169 vs.>188) and smaller longitudinal ventral scale count (83–92 vs.>96).

Genetically, the new species is highly distinct from all species in subclade A5, and differs at least from L. guibei by a less distinctly expressed lateral spine at the tail base of males (vs. presence of a distinct, large spine). Furthermore, the longitudinal dorsal scale count is smaller than in all known individuals of subclade A5.

The new species differs from its sister lineage, L. salvi (described above), by a lower longitudinal dorsal scale count (159–169 vs. 211–217) and a lower ventral scale count (83–92 vs. 107–112). The two sister species also differ by a high genetic divergence of 11.2–12.6% in the 16S gene, and do not share haplotypes in RAG1 despite occurring in geographical proximity.

For a distinction from additional species newly named and described herein, see the respective diagnoses below.

Etymology. We are pleased to dedicate this beautiful gecko species to Beate Röll, in recognition for her substantial contributions to Lygodactylus biology and phylogeny. The name is a matronym (i.e., a noun in the genitive case).

Description of the holotype. Adult female, in a good state of preservation, the right hind limb is partly removed as a source of tissue for molecular analysis ( Fig. 15 ). SVL 35.9 mm, TAL 39.6 mm; for other measurements see Table 1 . Head and neck thick, body broader than head. The distance from the tip of the snout to the anterior border of the eye (3.8 mm) is less than the interorbital distance anteriorly (4.2 mm), and greater than the distance between the eye and ear opening. Snout covered with granular scales larger than those on the rest of the dorsum. Nostril surrounded by five scales: rostral, first supralabial, and three supranasals. Mental scale undivided; no contact between posterior projection of mental scale and first infralabial; two asymmetrical postmental scale with five postpostmental scales; seven infralabial scales; seven supralabial scales; two internasal scales; granular dorsal scales; dorsum with small, homogeneous, granular, and unkeeled scales of similar size to those on trunk, smaller than on head and tail, the scales on limbs can be slightly larger; 169 dorsal scales longitudinal along the body; 92 ventral scales between mental and cloaca; venter with large homogeneous smooth scales; first finger present but very small, not bearing a claw; three pairs of subdigital lamellae on the fourth toe; no dorsolateral tubercles; tail without whorls; small lateral spines at the base of the tail.

Based on available photographs ( Fig. 18A–B ), the life coloration of the holotype exhibited a distinct pattern of dark brownish to yellowish stripes on the dorsum reaching from the eye to base of the tail. The stripes continue in an irregular pattern of more elongated dark and brighter spots on the caudal spine. The dark wide area on the back is slightly emarginated at the level of the hindlimbs before ending at the base of the tail. The flanks and limbs are gray to brownish ( Fig. 18A ). The ventral side is whitish with few small brown spots predominately on the throat and the tail ( Fig. 18B ). The specimen has darkened after 6 years of preservation in ethanol; however, the striped pattern is still distinctly visible.

Variation. The coloration of the dorsum is characteristic with a distinct pattern of dark brownish to yellowish stripes on the dorsum with a variable strength of expression on the tail ( Fig. 18A and 18E ), which appears to weaken greatly or be lost upon regeneration ( Fig. 18C ).

TABLE 1. (Continued)

TABLE 1. (Continued)

TABLE 1. (Continued)

TABLE 1. (Continued)

TABLE 1. (Continued)

The examined male paratype specimen (ZSM 556/2014) is almost the same size as the holotype with a SVL of 36.0 mm and has a longer tail (45.3 mm) and hindlimbs (HIL/SVL 0.45). On the fourth toe it has four instead of three subdigital lamellae, which differs from all other examined specimens. Unlike the holotype it has tubercles between the limbs (6) that consist of one scale each. It has fewer dorsal (159) and ventral scales (83). These differences could be due to different sex or just random variation.

Natural history. Specimens of this species were collected sleeping at night on roosts up to 1 m above the ground in Ampotsidy. UADBA-R 70855 was found sleeping on the tip of a Pandanus frond. It occurs in close sympatry with Lygodactylus winki sp. nov., described below.

Distribution. L. roellae is known from (1) the type locality Ampotsidy and (2) Andrevorevo.

Figures

FIGURE 15. Dorsal and ventral views of preserved holotypes of new species of the Lygodactylus madagascariensis group named in the current study.

FIGURE 18. Photos of Lygodactylus roellae sp. nov. in life. A and B, adult female holotype ZSM 49/2016 (MSZC 0072) from Ampotsidy. C,D, adult female paratype UADBA-R 70855 from Ampotsidy. E, male paratype ZSM 556/2014 (DRV 6289) from Andrevorevo.