Cyrtodactylus stresemanni, Rösler, Herbert & Glaw, Frank, 2008

Rösler, Herbert & Glaw, Frank, 2008, A new species of Cyrtodactylus Gray, 1827 (Squamata: Gekkonidae) from Malaysia including a literature survey of mensural and meristic data in the genus, Zootaxa 1729, pp. 8-22 : 9-20

Cyrtodactylus stresemanni sp. nov.

Figs. 1–8

Holotype ZSM 249/1911 (field number "coll. E. Stresemann 185"), adult male, from "Batang Padang-Tal, 800–900 m " (jar label) [near the town Tapah, Perak province, Malaysia], collected by E. Stresemann, on 7 Oktober 1910 during the second "Freiburger Molukken Expedition".

Diagnosis: A medium-sized Cyrtodactylus with a total length of 190 mm (SVL 95.5 mm), head distinct from neck, body slender, venter flat, tail base not enlarged. Cyrtodactylus stresemanni can be distinguished from all other species of the genus by the following combination of characters: 13 supralabials; 10 infralabials; 13 longitudinal rows of dorsal tubercles; conical tubercles along the lateral skin folds; 63 ventrals between the lateral skin folds; a deep, narrow preanal groove; femoral scales and femoral pores not enlarged; subcaudals not enlarged; tubercles on dorsal and ventral side of the tail; vertebral stripe grey-brown; three pairs of brown-olive, elongated markings on the back; tail with distinct bands.

Description of holotype: SVL 95.5 mm, TL 94.0 mm (incomplete), HL 25.0 mm, HW 18.0 mm, HH 10.2 mm, SH 44.0 mm, SE 11.4 mm, EE 9.6 mm, DE 5.0 mm, DEA 1.3 mm. Proportion of SVL / HL 3.82, SVL / SH 2.17, HL / HW 1.39, HL / HH 2.45, DE / DEA 3.85; SE / EE 1.19. Rostral scale 1.6 times broader than tall, as broad as mental, above with a straight, inversely, Y-shaped rostral suture. 13/13 supralabials (10/9 until center of eye), 4 scales between supralabial and eye; nostril in contact with rostral and first supralabial, 4/4 nasal scales, nasorostral scales 2 times larger than supranasals and 3 times larger than postnasals, 2 equally sized internasals (see Fig. 1 ); scales in contact with supralabials flat, smooth, equally sized as postnasals, scales on snout round to ovoid, conical, juxtaposed, median scales on snout 2 times larger than granules on head; snout and parietal region deepened; pupil vertical, anterior border straight, posterior border with 2 serrations; ciliaries anteriorly 3 times larger than posteriorly; ear opening oblique; interorbital region and skull posterior to interorbital region with small, round granules; several enlarged tubercles in the orbital region, 56 scales between the eyes; tubercles on posterior head and neck convex, 3 times larger than adjacent granules; no tubercles below a line marked by angle of mouth and ear opening. Mental triangular, broader than long; 10/ 10 infralabials; 2 postmentals, 3 times longer than broad, suture between postmentals separated from mental by more than 50%; 9 scales in contact with postmentals; scales on throat granular, of same size as interorbital scales (see Fig. 2 ). Dorsal scales granular, 2 times larger than interorbital scales, irregularly arranged; dorsal tubercles triangular, conical, keeled, arranged in 13 more or less regular longitudinal rows, in contact with 12 dorsals, 5–7 granules between two tubercles of one row, tubercles dorsolaterally 4 times larger than dorsals; lateral skin fold poorly developed with 17/17 large, conical tubercles, 2–7 (mostly 6–7) granules between tubercles (see Fig. 3 ). Ventral scales thickened, subimbricate, 2 times larger than dorsals, at midbody 63 ventrals between the lateral skin folds. Forelimbs dorsally with granules, mixed with conical and triangular, slightly keeled tubercles; hindlimbs dorsally with granules, mixed with conical and triangular tubercles, ventrally in femoral region a distinct border between large, slightly convex, imbricate scales anteriorly and small granules posteriorly, scales in femoral region not enlarged; ventral side of lower hindlimb with thickened, imbricate scales; fingers and toes with claws, without clearly recognizable webbing at the base, claw in contact with two scales, 13/12 subdigital lamellae below first toe (the 5/5 most basal scales enlarged) and 23/20 subdigital lamellae below fourth toe (10/7 enlarged). About 10 preanal pores in a deep, narrow, elongated groove, preanal groove in contact with 2 rows of enlarged, thickened, imbricate scales (see Fig. 4 ); 2/2 triangular, thickened, oblique, postanal tubercles (dorsally larger than ventrally). Tail round, with distinct whorls, not thickened at its base; tail dorsally with granules, 1.5 times larger than head scales, at the beginning and end of each whorl arranged in a regular transversal row; in first whorl dorsally 13 scale rows; first whorl with 10, third whorl with 9 and fifth whorl with 8 tubercles, arranged ring-shaped around the tail; tail tubercles dorsally and laterally ovoid, spiny, with single keel; ventrolateral and ventral tail tubercles flat, smooth, or keeled (see Fig. 5 and 6 ); subcaudals convex, subimbricate, at most 3 times larger than dorsal scales on tail.

Colour in preservative (ca. 70% alcohol, after almost 100 years): Head dorsally brown-olive, labials and ciliaries with a pattern of light and dark; a broad brown-olive stripe from nostril to anterior eye; neck with triangular, blackish-olive, darkly bordered spot; broad, brown-olive postocular stripe to neck; throat yellowolive; vertebral stripe grey-brown, anteriorly V-shaped, fusing at midbody with the light lateral colouration, posteriorly with the first band on the tail; dorsolaterally three distinctly bordered, brown-olive, elongated spots, the two anterior ones 4 times longer than broad, the posterior one in the region of the tail base 2 times longer than broad, the anterior one in contact with postocular stripe (see Fig. 7 ); ventral side olive, preanal region yellow-olive; tail dorsally with a narrow band at its base, followed by two broad, pale brown rings, broad interspace blackish-olive; tail ventrally olive, interrupted by the light rings.

Comparisons: Cyrtodactylus stresemanni is only known from a single individual which, however, is apparently distinguishable from all other Cyrtodactylus species by the presence of large tubercles on the ventral side of the tail. Furthermore, C. stresemanni differs by more ventral scales (see table 1) from C. aaroni Günther & Rösler, 2003 , C. adleri Das, 1997 , C. aequalis Bauer, 2003 , C. agusanensis (Taylor, 1915) , C. angularis (Smith, 1921) , C. annandalei Bauer, 2003 , C. ayeyarwadyensis Bauer, 2003 , C. baluensis (Mocquard, 1890) , C. biordinis Brown & McCoy, 1980 , C. brevidactylus Bauer, 2002 , C. brevipalmatus (Smith, 1923) , Cyrtodactylus buchardi David, Teynié & Ohler, 2004 , C. caovansungi Orlov, Truong, Nazarov, Ananjeva & Sang, 2007 , C. chanhomeae Bauer, Sumontha & Pauwels, 2003 , C. chauquangensis Quang, Orlov, Ananjeva, Johns, Thao & Vinh, 2007 , C. chrysopylos Bauer, 2003 , C. condorensis (Smith, 1921) , C. cracens Batuwita & Bahir, 2005 , C. darmandvillei (Weber, 1890) , C. derongo Brown & Parker, 1973 , C. deveti ( Brongersma, 1948) , C. edwardtaylori Batuwita & Bahir, 2005 , C. elok Dring, 1979 , C. feae ( Boulenger, 1893) , C. fraenatus ( Günther, 1864) , C. fumosus (Müller, 1895) , C. gansi Bauer, 2003 , C. gubernatoris ( Annandale, 1913) , C. ingeri Hikida, 1990 , C. interdigitalis Ulber, 1993 , C. intermedius ( Smith, 1917) , C. irianjayaensis Rösler, 2000 , C. irregularis (Smith, 1921) , C. jarujini Ulber, 1993 , C. jellesmae ( Boulenger, 1897) , C. khasiensis ( Jerdon, 1870) , C. laevigatus ( Darevsky, 1964) , C. malcolmsmithi ( Constable, 1949) , C. matsuii Hikida, 1990 , C. mimikanus (Boulenger, 1914) , C. oldhami (Theobald, 1876) , C. papilionoides Ulber & Grossmann, 1991 , C. paradoxus ( Darevsky & Szczerbak, 1997) , C. peguensis ( Boulenger, 1893) , C. phongnhakebangensis Ziegler, Rösler, Herrmann & Vu 2003 , C. quadrivirgatus Taylor, 1962 , C. russelli Bauer, 2003 , C. ramboda Batuwita & Bahir, 2005 , C. seribuatensis Youmans & Grismer, 2006 , C. sermowaiensis ( De Rooij, 1915) , C. slowinskii Bauer, 2002 , C. soba Batuwita & Bahir, 2005 , C. subsolanus Batuwita & Bahir, 2005 , C. sumonthai Bauer, Pauwels & Chanhome, 2002 , C. sworderi ( Smith, 1925) , C. thirakhupti Pauwels, Bauer, Sumontha & Chanhome, 2004 , C. tigroides Bauer, Sumontha & Pauwels, 2003 , C. tiomanensis Das & Lim, 2000 , C. tuberculatus (Lucas & Frost, 1900) , C. variegatus (Blyth, 1859) , C. wakeorum Bauer, 2003 , C. wetariensis ( Dunn, 1927) , and C. yoshii Hikida, 1990 . Cyrtodactylus stresemanni differs by a larger SVL and the presence of a preanal groove from C. annulatus (Taylor, 1915) , C. consobrinoides ( Annandale, 1905) , and C. malayanus ( De Rooij, 1915) ; by a smaller SVL and the absence of preanofemoral pores from C. loriae (Boulenger, 1898) , C. louisiadensis ( De Vis, 1892) , and C. novaeguineae (Schlegel, 1837) ; by small instead of enlarged subcaudals from C. consobrinus (Peters, 1871) ; by fewer dorsal rows of tubercles from C. lateralis ( Werner, 1896) and C. murua Kraus & Allison, 2006 ; by the absence of femoral pores from C. redimiculus King, 1962 (table 1).

Eleven Cyrtodactylus species ( agamensis , aurensis , cavernicolus , marmoratus , papuensis , philippinicus , pubisulcus , pulchellus , rubidus , sadleiri , semenanjungensis ) and C. stresemanni are known to have a preanal groove. C. stresemanni differs by a larger SVL and fewer dorsal rows of tubercles from C. agamensis (Bleeker, 1860) , C. cavernicolus Inger & King, 1961 , C. papuensis ( Brongersma, 1934) , C. philippinicus ( Steindachner, 1867) , and C. pubisulcus Inger, 1957 ; by more ventral scales and fewer dorsal rows of tubercles from C. marmoratus Gray, 1831 , C. sadleiri Wells & Wellington, 1985 , and C. semenanjungensis Grismer & Leong, 2005 ; by more ventral scales and not enlarged subcaudals from C. aurensis Grismer, 2005 , C. pulchellus Gray, 1828 , and C. rubidus ( Blyth, 1860) (see table 1).

Cyrtodactylus stresemanni differs from all species of the subgenus Geckoella sensu Rösler (2000) by larger SVL and the presence of a preanal groove and furthermore by more ventral scales from C. (Geckoella) albofasciatus (Boulenger, 1885) , C. (G.) deccanensis ( Günther, 1864) , C. (G.) jeyporensis (Beddome, 1877) , C. (G.) nebulosus (Beddome, 1870) , and C. (G.) triedrus ( Günther, 1864) and by more supralabials and infralabials from C. (G.) collegalensis (Beddome, 1870) and C. (G.) yakhuna (Deraniyagala, 1945) .

Further characters (head tubercles, tubercles on the lateral skin fold, tubercles on limbs, subdigital lamellae below fourth toe) which allow a distinction of C. stresemanni from other Cyrtodactylus species are provided in table 1. Among the Cyrtodactylus species which are known to have a preanal groove there is only one with a junior synonym (syn. fide De Rooij 1915): Cyrtodactylus marmoratus quadrilineatus Werner, 1896 . This taxon differs from C. stresemanni by the lack of tubercles on the lateral skin folds ( Werner 1896).

Etymology: The species is dedicated to the famous ornithologist Erwin Stresemann who has collected the holotype.

Distribution and habitat: The single known specimen of C. stresemanni was collected almost 100 years ago in a mountain range that was largely covered with rainforest and inhabited by a native tribe called "Sakai". Since no additional specimens have been discovered in the meantime, it appears likely that the new species might be locally endemic in western Malaysia. Stresemann provided additional information about the expedition in a letter to his parents ( Haffer 1997: 864–866) which may allow future expeditions to locate the type locality more precisely: " Wie ich Euch schon schrieb, erfuhren wir hier bei unserer Ankunft am 15. September, dass unser Boot erst am 30. Oktober hier eintreffen würde. Wir entschlossen uns bald zu einer kleinen Expedition nach der Halbinsel und zwar in das Gebirge von Perak, um dort zoologisches und ethnologisches Material zu sammeln. Nach etwa 10 Tagen waren wir mit unseren Vorbereitungen zu Ende und fuhren mit der äußerst komfortablen Bahn Singapore-Penang, die meist mitten durch unzugänglichen Urwald führt, in etwa 6 Stunden zu unserem Ausgangspunkt Tapah, ein größerer Ort mit buntgemischter Bevölkerung [...]. Nach 3 Tagen begann von hier der Marsch ins Gebirge, das Gepäck konnte zunächst mit Ochsenwagen 12 Meilen weit geführt werden, wo sich ein stattliches Rasthaus befand. Wir nahmen hier abermals mehrtägigen Aufenthalt, ich begann zu sammeln und wir machten unsere erste Bekanntschaft mit den Sakais [...] und wir brachten es nach einigen Tagen dahin, daß wir mit 21 Sakaiträgern zu unserem weiteren Marsch in die höheren Gebirgslagen aufbrechen konnten: nach 3 interessanten Marschtagen, stets durch dichten Urwald mit oft sehr schönen Flußtälern und herrlicher Palmenvegetation, erreichten wir in etwa 1200 m Höhe unser vorgesehenes Stammquartier. Hier an der Grenze der Staaten Perak und Parang befand sich eine vom Staate vor vielen Jahren errichtete, mit Blechplatten gedeckte Hütte, die bereits vor uns von einer Expedition als Stammquartier genutzt worden war. Wir gedachten hier etwa 3 Wochen zu bleiben und zu sammeln. Zoologisch war alles hier sehr interessant und wertvoll, auf Exkursionen erreichten wir den Gipfel des höchsten Berges der Umgebung mit 1800 m ".

Systematic position: The large tubercles on the ventral side of the tail of C. stresemanni appear to be unique in the genus Cyrtodactylus . The combination of the characters: (1) tubercles on the lateral skin fold, (2) presence of a preanal groove, and (3) not enlarged subcaudals reveal morphological similarities to C. papuensis , C. philippinicus , C. pubisulcus , and C. rubidus . However, close relationships of C. stresemanni with any of these species appear to be unlikely. The closest relative of C. papuensis is possibly C. marmoratus (Rösler et al. in press). In C. philippinicus the preanal pores are visible and not hidden in the preanal groove. In C. annulatus , the preanal pores are visible and arranged in a very acute angle (see Fig. 2 in Brown & Alcala 1978). C. rubidus was placed in the C. pulchellus group ( Smith 1935). The geographic distribution also does not suggest close relationships of C. stresemanni with one of the four species which are all island-endemics without recognizable relations to Malaysia: C. papuensis (New Guinea), C. philippinicus ( Philippines) , C. pubisulcus (Borneo) , and C. rubidus (Andaman islands). C. stresemanni shares a close overall resemblance to two other Malaysian species, C. brevipalmatus and C. elok (Grismer, pers. comm.). However, C. stresemanni differs from C. brevipalmatus by larger maximum SVL (95.5 vs. 72 mm), presence of tubercles on the head, number of ventral scales (63 vs. 35–44), presence of a preanal groove, absence of femoral pores and nonenlarged median subcaudals (see table 1). C. stresemanni differs from C. elok by larger maximum SVL (95.5 vs. 67.5 mm), number of supralabials (13 vs. 11–12), number of longitudinal rows of dorsal tubercles (13 vs. 6–10), number of ventral scales (63 vs. 44), presence of a preanal groove, number of preanal pores (10 vs. 8), number of subdigital lamellae/scales on 4th toe (20–23 vs. 18–19), and non-enlarged median subcaudals (see table 1).

Figures

FIGURE 1. Nasal region of Cyrtodactylus stresemanni, holotype ZSM 249 / 1911.

FIGURE 2. Mental region of Cyrtodactylus stresemanni, holotype ZSM 249 / 1911.

FIGURE 3. Lateral skin fold with tubercles of Cyrtodactylus stresemanni, holotype ZSM 249 / 1911.

FIGURE 4. Preanal groove of Cyrtodactylus stresemanni, holotype ZSM 249 / 1911.

FIGURE 5. Dorsal view of anterior part of tail of Cyrtodactylus stresemanni, holotype ZSM 249 / 1911.

FIGURE 6. Subcaudals and tubercles on ventral side of the tail of Cyrtodactylus stresemanni, holotype ZSM 249 / 1911.

FIGURE 7. Holotype (ZSM 249 / 1911) of Cyrtodactylus stresemanni, dorsal view.

FIGURE 8. Holotype (ZSM 249 / 1911) of Cyrtodactylus stresemanni, ventral view.