Phelsuma gouldi, Crottini, Angelica, Gehring, Philip-Sebastian, Glaw, Frank, Harris, James, Lima, Alexandra & Vences, Miguel, 2011

Crottini, Angelica, Gehring, Philip-Sebastian, Glaw, Frank, Harris, James, Lima, Alexandra & Vences, Miguel, 2011, Deciphering the cryptic species diversity of dull-coloured day geckos Phelsuma (Squamata: Gekkonidae) from Madagascar, with description of a new species, Zootaxa 2982, pp. 40-48 : 42-46

publication ID	https://doi.org/ 10.5281/zenodo.208124
DOI	https://doi.org/10.5281/zenodo.6189256
persistent identifier	https://treatment.plazi.org/id/03E48788-FFA0-FFBA-CF8F-52D7FDB5757A
treatment provided by	Plazi
scientific name	Phelsuma gouldi
status	sp. nov.

Treatment

Phelsuma gouldi sp. nov.

( Figs. 2–3 View FIGURE 2 View FIGURE 3 )

Holotype. ZSM 804/2010 ( ZCMV 13056), adult female, collected in Anja Reserve ( Fig. 1 View FIGURE 1 ), 13 km south of Ambalavao 21°51'2.64'' S, 46°50'33.80'' E, 949 m a.s.l., Haute Matsiatra Region, Fianarantsoa province, southern central Madagascar, on 9th December 2009 by Angelica Crottini, D. James Harris, Iker A. Irisarri, Alexandra Lima, Solohery Rasamison and Emile Rajeriarison.

Paratypes. None.

Diagnosis. A presumably medium-sized, greyish-brown Phelsuma (SVL 45.1 mm, TL 81.5 mm) with an irregular pattern of brown to black lines and spots ( Fig. 2 View FIGURE 2 ).

It differs from all other Phelsuma species, except for P. b o r a i, P. mutabilis , P. breviceps , P. standingi , and P. masohoala Raxworthy & Nussbaum by its cryptic life colouration without traces of green.

Phelsuma gouldi differs from P. standingi by its smaller total length (TL 81 mm vs. up to 279 mm), number of supralabials (7/6 vs. 9–12), number of infralabials (6 vs. 7–8) and shows a distinct life colouration (brown-greyish dorsal colouration with irregular blackish stripes and dots vs. grey or bluish-green with dark reticulation and with greenish head and bluish tail). It differs from P. masohoala by the number of supralabials (7/6 vs. 8–9), number of infralabials (6 vs. 7), smooth dorsal scales on body and tail vs. keeled dorsal scales, a distinct life colouration (brown-greyish dorsal colouration with irregular blackish stripes and dots vs. a white and black pigmentation), and by a single V-shaped chevron along the lower suture of infralabials vs. up to three V-shaped chevrons on the throat. Phelsuma gouldi differs from P. breviceps by a slender snout vs. a very stout snout, by the number of transversely enlarged subdigital lamellae under the fourth toe of left/right foot (7/9 vs. 11/10), by the presence of a single Vshaped chevron along the lower suture of infralabials vs. absence, and by a set of throat scalation characteristics (for comparison see Fig. 3 View FIGURE 3 of this study and Fig. 3 View FIGURE 3 in Glaw et al. 2009): a triangular-shaped mental in P. gouldi (vs. a bell-shaped mental in P. breviceps ), two postmental scales (vs. one postmental scale), four rows of enlarged postmentals (vs. one), the minimum number of scales needed to connect the suture between the second and third infralabial from the left to the right is 10 in P. gouldi vs. 14 in P. breviceps .

The most similar species to P. gouldi are P. borai and P. mutabilis . Phelsuma gouldi differs from P. borai by a lower number of transversely enlarged subdigital lamellae under the fourth toe (7/9 vs. -/11), a lower number of supralabials (7/6 vs. 10/9), one internasal scale (vs. three), the absence of a distinct concave groove between the nasals (vs. presence), by the presence of a V-shaped chevron along the lower suture of infralabials (vs. absence), and by a different configuration of the throat scalation (see Fig. 3 View FIGURE 3 , comparison A with C): two postmental scales bordering the mental scale for about one-third in P. gouldi vs. two postmental scales border about one half of the mental scale in P. borai , the minimum number of scales needed to connect the suture between the second and third infralabial from the left to the right is 10 vs. 5, presence of 4 rows of enlarged postmentals vs. 5, and by a horizontally divided third infralabial vs. undivided. Phelsuma gouldi differs from the P. mutabilis specimens examined in Glaw et al. (2009) comprising thirteen specimens from Toliara (ZSM 945/2003, ZSM 948/2003), Toliara-Arboretum (ZSM 587/2000, ZSM 588/2000), Ampanihy-Tranoroa (ZSM 186/2004), unknown localities (MNHN 1895.152, MNHN 1895.154), Androy Nord (MNHN 1901.150, MNHN 1901.151) and Menabe (SMF 9470-9473) by a lower number of transversely enlarged subdigital lamellae under the fourth toe (7/9 vs. min. 9/10 to max. 11/ 11) and by a different configuration of the throat scalation (see Fig. 3 View FIGURE 3 , comparison A with B): triangular-shaped mental scale vs. bell-shaped, the minimum number of scales needed to connect the suture between the second and third infralabial from the left to the right is 10 in P. gouldi vs. 5 in P. mutabilis , 4 rows of enlarged postmentals vs. 3 rows, and by a horizontally divided third infralabial vs. undivided. Furthermore, P. gouldi differs from P. mutabilis , P. b o r a i, and P. breviceps , and all other Phelsuma species for which molecular data are available, by a substantial genetic differentiation (see Fig. 4 View FIGURE 4 ).

Description of the holotype. Well preserved, with regenerated tail autotomized after the first half. Autotomized tail part preserved separately. The tail tip (ca. 3 mm) was removed as a tissue sample. Body and head flattened dorsoventrally. Head slightly wider than neck, about as wide as body. Ear opening roundish. Tail shorter than snout-vent length, dorsoventrally flattened in cross section. No distinct tail whorls recognisable. Digits strongly expanded at tips, first finger and first toe vestigial, comparative finger and toe length 1<2<5<3<4. Number of (transversely enlarged, left/right) subdigital lamellae under fourth toe 7/9. Rostral scale wider than tall and less wide than mental scale. Presence of distinct rostral cleft in dorsal process of rostral scale. One internasal scale. Nostril in contact with four scales, the first supralabial, the nasal and two small postnasals, but no contact with rostral. Pupil round. Dorsal and lateral scales of head smooth, nearly flat, becoming increasingly smaller on the posterior regions of the head. Dorsal and lateral scales of body have approximately unifom size and almost round shape. From the tail base on, enlarged almost rectangular smooth dorsal scales on the tail. All ventral and subcaudal scales smooth. The median row of subcaudal scales irregularly enlarged transversely. Mental scale largely triangular, bordered posteriorly by a pair of elongate, irregular hexagonal to pentagonal postmentals. Postmentals contact mental, first infralabial and three gulars. Gulars decrease gradually in size posteriorly. Number of supralabials (left/right) 7/ 6; number of infralabials (left/right) 6/6. The fifth supralabial on the left seems to be horizontally divided into two enlarged rectangular scales.

Measurements: SVL 45.1 mm; tail length 36.4 mm (plus ca. 3 mm that were taken as tissue sample); head width (at widest point) 8.6 mm; snout length (anterior edge of eye to tip of snout) 5.4 mm; horizontal eye diameter 2.1 mm; ear opening diameter 0.7 mm; eye-ear distance 3.1 mm; internarial distance 1.5 mm; nostril-eye distance 5.3 mm, axilla-groin distance 20.5 mm; forelimb length (from axilla to tip of longest finger) 14.6 mm; hindlimb length (from groin to tip of longest toe) 18.9 mm.

Colouration: Colour after nearly one year in alcohol similar to that shortly after being euthanised ( Fig. 2 View FIGURE 2 ). Unfortunately no pictures of the holotype in life are available, but a photograph provided by H.-P. Berghof resembling the holotype and possibly showing a P. gouldi from near Betroka ( Fig. 5 View FIGURE 5. A ) suggests that colouration in life and in preservative are probably similar as is also the case in related species. Ground colour of head, body, tail and dorsal parts of limbs dorsally and laterally brown-grey with irregular blackish stripes and dots. Several dark framed light brown spots dorsally on neck, body and limbs. A thin, dark medio-dorsal line extending from mid-body towards neck, where it divides into two thin dark lines extending in direction of snout tip converging between eye socket and nostril. A black band from nostril to anterior eye, continuing from posterior eye above ear opening, fading out as single thin dark line shortly behind neck. Another dark band between mouth corner and ear opening. A distinct dark lateral band starting from neck extending posteriorly until the tailbase, shortly behind the groin which marks the colour border between dorsal and ventral part of animal. Between axilla and groin and underneath the lateral band an irregular line of single spots, which continues on the tail where it fades out in posterior half.

Supralabials and infralabials greyish-white with single dark pigmentations. Thin dark line along first two infralabials extending in posterior direction on gular scales, curving in direction to ear opening, fading shortly before that. Throat, chest, venter, and ventral parts of forelimbs and hindlimbs greyish-white. Toe tips on hand and feet dark grey-coloured.

Distribution, conservation and IUCN Red List status. The new species is currently known only from the type locality within the Anja Reserve ( Fig. 1 View FIGURE 1 ), but further investigations are required to understand its actual distribution. It is possible that records of P. mutabilis from the central areas of Madagascar actually refer to P. gouldi . For instance, Hallmann et al. (2008) cite an observation by H.-P. Berghof who found P. mutabilis between the Horombe Plateau and the Andringitra massif at an altitude above 1000 m a. s. l. On request H.-P. Berghof (pers. comm.) was able to define this locality more precisely as near Betroka which is some 160 km south-west of the type locality, suggesting that P. gouldi might not be a local endemic of the Ambalavao region.

In the area of the type locality there was no evidence of mineral or precious stone extraction or collecting for the pet-trade, but deforestation for agriculture, logging and cattle grazing was observed in all surrounding areas. It is likely that P. gouldi will qualify for inclusion in one of the threatened categories, but due to the currently restricted knowledge on this species we suggest to consider its conservation status as “Data Deficient” according to IUCN criteria ( IUCN 2001).

Habitat and habits. The holotype of P. gouldi was found around 4 p. m. on a tree trunk at a roosting height of about 2.5 meters. The tree was in an open and sunny spot inside a forest fragment. However, unpublished records report the sighting of P. mutabilis -like specimens on granitic rocks in Anja (Böhle, pers. comm.), and this record most probably refers to P. gouldi . No other Phelsuma species were found around the type locality.

Etymology. We name this new species in honour of Stephen Jay Gould, a paleontologist, evolutionary biologist, historian of science and supreme writer of popular science who also provided invaluable contributions to the public appreciation of natural history and of science in general.

Available names. Two junior synonyms are currently recognised for Phelsuma mutabilis and need to be considered as possible earlier available names for P. g o u l d i (see Hallmann et al. 2008; Glaw et al. 2009): Phelsuma androyensis Mocquard (originally described as Phelsuma androyense ) and Phelsuma micropholis Boettger. The synonymy with P. mutabilis of both taxa was discussed in detail in Glaw et al. (2009). Based on comparisons of throat scalation and the number of transversely enlarged subdigital lamellae under fourth toe (11/10 and 11/ 11 in P. androyensis and 10/11, 11/10, 10/10, 11/ 11 in P. micropholis ; vs. 7/ 9 in P. gouldi ) it is evident that these two nomina are not conspecific with Phelsuma gouldi (see Table 1 in Glaw et al. 2009 for additional details).

Mitochondrial DNA variation, differentiation and phylogenetic relationships. The phylogenetic analyses resulted in a tree with largely unresolved basal relationships ( Fig. 4 View FIGURE 4 ) but with good support for the monophyly of P. mutabilis samples from across its range and clearly indicating the distinctness of P. gouldi from all the other three currently recognised species of the P. mutabilis group. The uncorrected genetic distance of P. gouldi to the three other Phelsuma species is: 8.1% to P. mutabilis , 12.8% to P. breviceps , and 8.5% to P. borai . The phylogenetic analyses identified three major mitochondrial clades within P. mutabilis . Clade 1, although not resolved, encompasses samples of P. mutabilis from the south east (Tranomaro), south west (Ifaty and Ejeda), and west (Makay and Antsalova); clade 2 includes the samples of P. mutabilis from the north west (Ankarafantsika) and from a locality between Tranoroa and Ampaniny (south west); finally, only samples coming from Toliara in the south west belong to the clade 3 (see Fig. 4 View FIGURE 4 ). Genetic distances within P. mutabilis amount to 4.7% between the clades and range between 0.2% to 4.5% within clades.