(Squamata: Gekkonidae: Phyllopezus) from Northwestern Peru
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Description of a new gecko from northwestern Peru SALAMANDRA 42 2/3 145-150 Rheinbach, 20 August 2006 ISSN 0036-3375 A remarkable discovery: description of a big-growing new gecko (Squamata: Gekkonidae: Phyllopezus) from northwestern Peru CLAUDIA KOCH, PABLO J. VENEGAS & WOLFGANG BÖHME Abstract. A new species of Phyllopezus is described from the dry forest of the upper Marañon basin (Department of Amazonas, Peru), in the northern portion of the Cordillera Central at an elevation of 900-1000 m a.s.l.. The new species differs from all described species by its large size, the absence of enlarged tubercles on head, limbs and tail, and only indistinct rows of small and flat tubercles on the dorsum. Key words. Squamata, Gekkonidae, Phyllopezus, new species, dry forest, Peru. Introduction collected in herpetological terms, and some regions have not been explored at all (LEHR In the Andes of northern Peru (Departments 2002, CAMPBELL & LAMAR 2004). As study of Piura, Cajamarca, Amazonas and San Mar- expands into these previously neglected ar- tin) the major structural and physiographic eas, numerous new records and descriptions break known as the “Huancabamba depres- of new species are published each year. sion” is found, consisting of a complex sys- A four day trip in the dry forest of the tem of relatively low ridges, basins and deep upper Marañon basin was made in July 2005, valleys (DUELLMAN & PRAMUK 1999). The searching for species occurring in this region. low altitude of the Andes in this region cause A comparatively large and obviously unde- fragmentation of montane habitats, and in- scribed species of gecko was found during troduce a complex mixture of environments the research, which, with a maximum known (CADLE 1991). snout-vent length (SVL) of 115 mm, is the One of these habitats is the dry forest of third largest gecko in South America. Only the upper Marañon basin which extends from Thecadactylus rapicauda HOUTTUYN, 1782, the Huancabamba depression to the deep val- which reaches 126 mm SVL and Phyllope- ley of the upper Marañon basin between the zus periosus RODRIGUES, 1986, which reaches Cordillera Occidental and Cordillera Cen- 120 mm SVL, are bigger. Herein we describe tral. Herpetological exploration of the upper this new species from the northern part of the Marañon basin in the last three decades has Cordillera Central, Peru. been fruitful and some new species have been discovered e.g., anurans of the gen- era Colosthetus (DUELLMAN 2004) and Eleu- Materials and methods therodactylus (DUELLMAN & PRAMUK 1999), gekkonid lizards of the genus Phyllodactylus All specimens collected were preserved in (DIXON & HUEY 1970), and tropidurid lizards 96 % ethanol and stored in 70 % ethanol. of the genus Stenocercus (FRITTS 1972, CA- Measurements of the head were taken with DLE 1991). a Vernier caliper (nearest 0.1 mm), measure- Due to the complex geography and di- ments of body and tail were taken by use of verse terrain, Peru has not been adequately a tape measure. Data from other Phyllopezus © 2006 Deutsche Gesellschaft für Herpetologie und Terrarienkunde e.V. (DGHT) http://www.salamandra-journal.com 145 CLAUDIA KOCH et al. species were taken from literature sources small granules on the dorsum; in some and examination of preserved material of the specimens few, slightly enlarged tubercules Zoologisches Forschungsmuseum Alexander present on the dorsum but seldom forming Koenig (ZFMK). The holotype and two of regular rows; enlarged tubercles absent from the paratypes were deposited at the Museo de head, limbs and tail; distal infradigital lamel- Historia Natural de la Universidad Nacional lae single; claw extends much beyond dilated Mayor de San Marcos (MHNSM), three part of basal phalanx. paratypes were deposited at the ZFMK. Comparisons: This species is distinguished from Phyllopezus periosus RODRIGUES, 1986 Results and discussion from Brazil and Phyllopezus pollicaris SPIX, Generic assignment 1825 from Argentina, Bolivia, Brazil and Paraguay (see Fig. 5) by the absence of en- Phenetically similar to Aristelliger COPE, larged, regular rows of trihedral tubercles on 1862 from the Caribbean. However, Aristel- the dorsum and from P. pollicaris also by liger is characterized by a unique synapo- larger size – maximum snout-vent length, morphy, the hemipenial bones (KLUGE 1982, 115 mm rather than 95 mm (VANZOLINI 1953, RÖSLER 1995, RÖSLER & BÖHME in press). Ab- RODRIGUES 1986). sent here. Characters of Phyllopezus PETERS, 1878 from South America are in agreement, Description of holotype: Rostral about twice except for the tubercles, but these vary in as wide as high with a short median groove other gecko genera (e.g. in the genus Hemi- of about one-third of length of rostral; nostril dactylus; RÖSLER 1995), too. According to surrounded by rostral, first labial, nasorostal, A. M. BAUER (pers. comm.) preliminary mo- supranasal and postnasal; 18 scales between lecular data show that our new species indeed eye and postnasal; scales in loreal region clusters with other Phyllopezus. about two to three times larger than midor- bital scales; rear of head granular without intermixed tubercles; ten supralabials and Species description nine infralabials; ear diameter contained in eye diameter 4.3 times; mental bell-shaped, a Phyllopezus maranjonensis sp. n. bit longer than wide, bordered posteriorly by (Figs. 1-4) two postmentals; postmentals slightly larger than other chin shields; postmentals imme- Holotype: Museo de Historia Natural San diately followed by transverse row of three Marcos, MHNSM 19555, an adult male scales, followed by second row of two smaller from Quebrada Honda in the vicinity of scales; postmentals contact first infralabial of Balsas (06°49’S, 78°00’W, approximately each side; dorsum with 88 intermixed tuber- 900-1000 m above sea level), Provincia de cles, scattered irregularly; tubercles small, Chachapoyas, Departamento de Amazonas, rounded and somewhat flattened, only two Peru; collected on 10 July 2005 by C. KOCH to three times larger than granules (Fig. 3); and P. J. VENEGAS. postanal tubercles two on left side, three on right side; limbs, tail and head without Paratypes: MHNSM 19553, ZFMK 84995, tubercles; 31 scales across venter, 89 from two adult males; MHNSM 19554, ZFMK throat to vent; ventral scales about four times 84996-97, three adult females, all collected larger than scales beneath head; median row with the holotype. of scales beneath tail distinctly widened; la- mellar formula for hand 8-11-13-13-12, foot Diagnosis: A large species of Phyllopezus 6-12-14-12-13; Claw extends much beyond with a maximum known SVL of 115 mm; dilated part of basal phalanx. 146 Description of a new gecko from northwestern Peru Measurements of the holotype (in mm): gray and creamy-white bands. Snout-vent length 112.5, axilla-groin length 42.3, tail length 116.8, head length 32.2, head Distribution: The new species is only known width 22.5, eye diameter 5.7, ear diameter from the type locality. It is located in the 1.3, snout length 19.1, distance from eye to inter-Andean valleys of the upper Marañon ear 9.1. basin, in the vicinity of Balsas (Department In life, ground colour grayish tan; dor- of Amazonas), Peru. It was collected on the sum distinctly banded with broad maroon western slope of the northern portion of the band, followed by narrow dark brown band, Cordillera Central (see DUELLMAN & PRAMUK followed by broad band of ground colour; 1999), at an elevation of 900 to 1000 m above between rear of head and vent four of such sea level. sequences; margins of each band undulat- ing; colouration of dorsum continues on tail Natural history: Phyllopezus maranjonensis but more distinct, with brighter colouration; inhabits the dry forest of the upper Marañon limbs and head mottled with maroon; dorsal basin. According to BRACK (1986), this habi- surface of feet slightly lighter than ground tat forms part of the Equatorial Dry Forest colour; ventral surface of body dirty white Ecoregion. This ecoregion penetrates the with several small, dark dots on each scale, Pacific lowlands of northern Peru to the Ma- more dense on tail. rañon basin at the Abra of Proculla (BRACK In preservative, ground colour light gray; 1986), which is the lowest pass in the Andes bands on dorsum grayish or grayish-brown. between Colombia and southern Chile. Using the vegetation formations of DU- Variation: Snout-vent lengths of adult males ELLMAN & PRAMUK (1999) the dry forest of range from 104.5 to 112.5 mm (mean 107.7), the Marañon basin is known as thorn forest females from 99.8 to 115 mm (mean 107.4), (Fig. 6). This xeric habitat receives up to average for all adults 107.6 mm; tail length 500 mm of rainfall annually (DUELLMAN & ranges from 85 to 116.8 mm (44.5 to 50.9 per PRAMUK 1999), the forest being composed cent of total length); postmentals always con- principally of the following trees: Prosopis, tact first labial; scales from postnasal to eye Acacia, Capparis, and Pseudobombax, with vary from 17 to 20 (mean 18.5); scales across other drought-resistant trees, especially near venter range from 28 to 35 (mean 30.7), from streams (Bursera, Jacaranda, and Phithecolo- throat to vent from 77 to 98 (mean 88.5); dor- bium), and numerous cacti (Cereus, Opuntia, sal scales around midbody range from 117 to and Lemairocereus) that predominate on the 131 (mean 122.7); number of enlarged scales low hills of the Marañon River. in median row beneath tail vary from 58 to All individuals of Phyllopezus maranjon- 65 (mean 62); scales between postnasal and ensis were found at night perched generally eye vary from 17 to 20; supralabials range with the head pointing toward the ground, from 8 to 10 (mean 9.3), infralabials from from one to more than three metres above 7 to 10 (mean 8.4); number of intermixed the ground, on high and almost vertical rocks dorsal tubercles vary from 5 to 94 (mean of Quebrada Honda (Fig.