Lygodactylus schwitzeri, Vences & Multzsch & Gippner & Crottini & Glaw & Köhler & Rakotomanga & Rasamison & Raselimanana, 2024

Vences, Miguel, Multzsch, Malte, Gippner, Sven, Crottini, Angelica, Glaw, Frank, Köhler, Jörn, Rakotomanga, Sandratra, Rasamison, Solohery & Raselimanana, Achille P., 2024, Taxonomizing a truly morphologically cryptic complex of dwarf geckos from Madagascar: molecular evidence for new species-level lineages within the Lygodactylus tolampyae complex, Zootaxa 5468 (3), pp. 416-448 : 437-441

Lygodactylus schwitzeri sp. nov.

( Fig. 9–12 )

Remark. This species corresponds to the candidate species L. sp. 27 aff. tolampyae D of Gippner et al. (2021).

Holotype. ZSM 419/2000 (FGMV 2000.155), female ( Fig. 9–10 ), collected by F. Andreone, J.E. Randrinirina, and M. Vences at Berara Forest (Ambonihazo; 14.310°S, 47.915°E, 170 m a.s.l.), Sahamalaza Peninsula , Madagascar, on 18 February 2000.

Paratypes. Eight specimens: MRSN R1913–1918 and 1921–1922, five males and three females (see Table 2 ), with same collection data as holotype. These specimens were not genotyped but are included in the paratype series because (1) they agree with the holotype in morphological features, (2) were collected at the same site, and (3) only one lineage of the L. tolampyae complex was found at Sahamalaza.

Diagnosis. L. schwitzeri sp. nov. is characterized as a member of the L. tolampyae complex (and thereby distinguishable from all other Malagasy Lygodactylus not belonging to the complex) by combination of a mental scale semi-divided by a suture, broad contact of the posterior projection of the mental scale with the first infralabial scale, and three postmental scales; furthermore, characterized by absence of whorls on the tail, and a typical look of the head with relatively large eyes. The new species differs from L. tolampyae sensu stricto (as defined herein; mitochondrial lineages A+B and possibly G) by higher maximum and mean counts of dorsal scales despite overlap of ranges (mean 254 vs. 229; ranges 240–271 vs. 204–241; U-test, P<0.001), and possibly by a tendency towards broader posterior contact between mental scale and first infralabial scale in a high proportion of specimens. From L. morii and L. herilalai the new species cannot be clearly diagnosed morphologically. From a molecular perspective, the new species is characterized by numerous diagnostic nucleotide positions in the mitochondrial 16S rRNA gene: MolD identified a robust diagnostic nucleotide combination of a ‘T’ in the site 967, ‘T’ in the site 992, ‘C’ in the site 1001 (positions relative to the full 16S rRNA gene of Phelsuma guimbeaui ).

Description of the holotype. Female, in good state of preservation, tail missing. SVL 28.1 mm, TAL 2.8 mm (broken and missing); for other measurements, see Table 2 . Head and body have approximately the same width. The distance from the tip of the snout to the anterior border of the eye (3.7 mm) is larger than the anterior interorbital distance (3.6 mm), and greater than the distance between the eye and ear opening (2.8 mm). Snout covered with granular scales slightly larger than those on the dorsum. Nostril surrounded by 5 scales: rostral, first supralabial, one postnasal and two supranasals. The mental scale is semi-divided; contact between posterior projection of mental scale and first infralabial scale is around 30% of the infralabial scale length; three symmetrical postmental scales, followed by five postpostmentals; seven infralabial scales; eight supralabial scales; two internasal scales; granular dorsal scales; dorsum with small, homogeneous, granular, and unkeeled scales of similar size to those on trunk, slightly larger on limbs; 240 dorsal scales longitudinally along the body; 102 ventral scales between mental and cloaca; venter with larger homogeneous smooth scales; first finger present, small, but bearing a claw; three pairs of subdigital lamellae on the fourth toe; no dorsolateral tubercles; no observable lateral spines at the base of the tail.

After 23 years of preservation in ethanol ( Fig. 10 ), the specimen is brownish in colouration with a broad dark middorsal stripe above. This stripe appears to continue in an interrupted pattern on the tail, which cannot be described as it is missing. On the head is a darker spot, from which the dark stripe appears to start. The limbs are patternless. Each side of the neck has a whitish tubercle consisting of one scale. The ventral side is mostly whitish, with a few light brown spots on the throat. A dark blueish spot is probably not integument colouration but organs visible through the skin. The underside of the hind limbs is spotted with light-brown colour around the knees. In life ( Fig. 9 ), colouration was quite similar but more contrasting, with distinct light brown dorsolateral stripes.

Variation. For variation in morphometric and scalation characters, see Table 2 . Body size ranged between 26.3–30.6 mm in males and 28.1–30.7 mm in females.

Etymology. The species epithet is a patronym for Christoph Schwitzer, in recognition for his contribution to lemur research and nature conservation in Madagascar, specifically in the Sahamalaza Peninsula. The species epithet is a noun in the genitive case.

Natural history. Very poorly known. The species inhabits transitional forest ( Fig. 13 ). This is a quite common species in the Anabohazo Forest in Sahamalaza. Three individuals were found roosting at night at the extremities of leaves and stems at about 1.5–2 m above the forest floor of a narrow valley forest along a dried temporary stream in dry semi-deciduous forest. During the day, one individual was found active on tree trunk at 0.8 m on slope in dry semi-deciduous forest in the same area.

Distribution. According to available molecular data, the species is known from two sites on the Sahamalaza Peninsula: (1) Ambonihazo ( Berara Forest ) and (2) Ankarafa. Penny et al. (2017) further report a record of the L. tolampyae complex, probably referring to this species from (3) Analavory. However, this forest fragment has been entirely destroyed by uncontrolled burning in 2004 ( Penny et al. 2016).

Figures

FIGURE 9. Female holotype of Lygodactylus schwitzeri sp. nov., ZSM 419/2000 (FGMV 2000.155), from Berara Forest, Sahamalaza, in life, photographed in February 2000.

FIGURE 10. Preserved holotypes of the three new species of the Lygodactylus tolampyae complex described herein, photographed in May 2023.

FIGURE 11. Ventral views of the heads of the holotypes of the three new species of Lygodactylus described herein, and one representative specimen of L. tolampyae. The images on the right show the mental region magnified and strongly sharpened to improve visibility of sutures between scales. For the holotype of L. morii sp. nov., the typical arrangement of scales in the mental region in this species complex is labelled: M, mental scales (semi-divided by incomplete sutures), PM, post-mentals (typically three), IL1, first infralabial (which maintains a broad contact with the mental). Scale bars (referring to the images on the left) represent 1 mm.

FIGURE 12. Lateral views of the heads of the holotypes of the three new species of Lygodactylus described herein, and one representative specimen of L. tolampyae. The scale bar represents 1 mm.

FIGURE 13. Habitat of species of the Lygodactylus tolampyae complex. A. Dry deciduous forest at Ampijoroa (Ankarafantsika) where L. morii sp. nov. occurs in high densities. B. View of remains of dry deciduous Ampondrabe forest (habitat of L. morii sp. nov. and L. herilalai sp. nov.) with large areas of forest destroyed by fire in the foreground. C, D. Transitional forest on Sahamalaza Peninsula, habitat of L. schwitzeri sp. nov. E. Forest in the Tsingy de Bemaraha, habitat of L. tolampyae. All photos by the authors except A by P. Galán.