Taxonomic Revision of the Pseudogekko Compresicorpus Complex (Reptilia: Squamata: Gekkonidae), with Descriptions of Three New Species

Herpetological Monographs, 28 2014, 110–139 E 2014 by The Herpetologists’ League, Inc. TAXONOMIC REVISION OF THE PSEUDOGEKKO COMPRESICORPUS COMPLEX (REPTILIA: SQUAMATA: GEKKONIDAE), WITH DESCRIPTIONS OF THREE NEW SPECIES 1,6 2 3 1 1 CAMERON D. SILER ,LUKE J. WELTON ,DREW R. DAVIS ,JESSA L. WATTERS ,CONNER S. DAVEY , 4 5 6 ARVIN C. DIESMOS ,MAE L. DIESMOS , AND RAFE M. BROWN 1 Department of Biology and Sam Noble Oklahoma Museum of Natural History, University of Oklahoma, 2401 Chautauqua Avenue, Norman, OK 73072-7029, USA 2 Department of Biology, Brigham Young University, 401 WIDB, Provo, UT 84602, USA 3 Department of Biology, University of South Dakota, 414 E. Clark Street, Vermillion, SD 57069, USA 4 Herpetology Section, Zoology Division, Philippine National Museum, Rizal Park, Burgos Street, Manila, Philippines 5 University of Santo Tomas, Espana Boulevard, Manila, Philippines 6 Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, 1345 Jayhawk Boulevard, Lawrence, KS 66045-7593, USA ABSTRACT: Recent phylogenetic analysis of false geckos, genus Pseudogekko, revealed unrecognized diversity within these exceedingly rare and enigmatic Philippine forest geckos. Newly available genetic datasets revealed that two of the four currently recognized species are complexes of multiple, deeply divergent evolutionary lineages. In this paper we evaluate species diversity in the Pseudogekko compresicorpus Complex and describe three new species in this unique clade of endemic Philippine geckos. For nearly a century, P. compresicorpus has been recognized as a single, ‘‘widespread’’ species with a geographic range spanning three major faunal regions and several isolated islands. This perception of the species’ wide geographic range has persisted due to the rarity of this species. We evaluate morphological data, in light of a recent phylogenetic study on the genus, to define species limits in P. compresicorpus, finding character-based evidence that unambiguously supports the recognition of four unique evolutionary lineages within the complex, three of which we describe as new species. These evolutionary species correspond to monophyletic lineages supported in recent molecular studies. We also address the historically controversial generic affiliation of Pseudogekko labialis and conclude that this poorly known species is a member of the genus Lepidodactylus. All species recognized in this study possess allopatric geographic ranges and differ from congeners by numerous diagnostic characters of external morphology and, therefore, should be recognized as full species in accordance with any lineage-based species concept. This study nearly doubles the known diversity of Philippine false geckos. Key words: Biodiversity; Conservation; Endemism; False geckos; Philippines; Species complex; Taxonomy PHILIPPINE gecko diversity represents an gliding locomotion with highly specialized impressive array of diversification in morphol- cutaneousstructures(e.g.,Ptychozoon and ogy, behavior, and ecology (Brown and Alcala, Luperosaurus; Brown et al., 1997, 2012a; 1978). From ancient, micro-endemic lineages Dudley et al., 2007). with small ranges on larger islands (Ro¨sler Other than the work of Taylor (1922a), et al., 2006; Linkem et al., 2010) to several Brown and Alcala (1978) published the only widespread species groups (Siler et al., 2010), comprehensive systematic review of Philip- and to species limited to tiny isolated islets pine geckos. Their work summarized taxo- (Brown and Alcala, 2000; Brown et al., 2011a; nomic diversity, provided an identification Siler et al., 2012a), Philippine geckos are guide, and recognized 31 species. Many of quite ecologically variable, considering that these had been observed rarely in natural only 57 species are currently recognized conditions and were known only on the basis (PhilBREO, 2014). The archipelago’s gekko- of one or two specimens in museum collec- nids also range from morphologically conser- tions. Although Brown and Alcala’s (1978) vative gecko generalists (Brown and Alcala, foundational work has remained the only 1978) to delicate forest vegetation specialists synopsis of the archipelago’s geckos, species and to several lineages capable of derived diversity has now nearly doubled since its original publication. Remarkably, of the 6 CORRESPONDENCE: e-mail, [email protected] country’s 57 species, 47 (82%) are Philippine 110 2014] HERPETOLOGICAL MONOGRAPHS 111 FIG. 1.—Maximum clade credibility topology of Pseudogekko derived from Bayesian analyses in the recent phylogenetic study of Siler et al. (2014a). Numbers below nodes indicate maximum likelihood bootstrap values (left) and Bayesian posterior probabilities (right). Boxed numbers correspond to numbered sampling localities shown on the associated topographic map of the Philippines. endemics (Brown et al., 2008, 2009, 2011a,b). 2014a) for species of Pseudogekko. Yet even Despite this dramatic improvement in our in the absence of dense population genetic understanding of this predominantly endemic sampling, Siler et al. (2014a) revealed a fauna, a few genera are very poorly known considerable degree of cryptic genetic diver- (i.e., Luperosaurus; Brown et al., 2007, sity and high levels of genetic divergence 2011b, 2012a). A case in point is the between clades. As currently recognized, the extremely rare, endemic genus Pseudogekko distribution of each of these species spans (Taylor, 1915, 1922a), a group of four small, multiple recognized faunal regions or Pleisto- delicate, distinctly elongate, highly secretive, cene Aggregate Island Complexes (PAICs; and entirely arboreal forest geckos (Brown Brown and Guttman, 2002; Brown and and Alcala, 1978). Diesmos, 2009). In fact, as currently defined In the last two decades, our comprehensive (Brown and Alcala, 1978; Siler et al., 2012b), biodiversity surveys throughout the Philip- the species Pseudogekko compresicorpus is pines (e.g., Siler et al., 2012b; Brown et al., distributed across three distinct faunal regions 2013a,b) resulted in only a handful of (Luzon, Mindanao, and Visayan PAICs) and vouchered genetic samples (Siler et al., an isolated island group (Romblon Island 112 HERPETOLOGICAL MONOGRAPHS [No. 28 Group; Fig. 1). Currently, there are few In this study, we investigate species diver- examples of seemingly widespread species of sity within the Pseudogekko compresicorpus Philippine vertebrates that truly defy these Complex, with the understanding that several regional biogeographic boundaries (Brown of the divergent populations identified here and Diesmos, 2002, 2009; Brown et al., may represent threatened, and possibly en- 2002, 2013a). Phylogenetic studies support dangered, unique evolutionary lineages (Siler many species as more range-restricted, with et al., 2014a), worthy of both formal taxonom- patterns generally consistent with inferred ic recognition and prioritization for immediate PAIC formation (Siler et al., 2012c,d); Brown conservation action. The taxonomic revisions et al., 2013a). In fact, phylogenetic analyses herein are guided by the results of the recent reveal unique lineages of P. compresicorpus phylogenetic study on geckos of the genus with apparent distributions corresponding to Pseudogekko (Siler et al., 2014a). circumscribed biogeographic subregions of the archipelago (Brown and Diesmos, 2009; TAXONOMIC HISTORY Brown et al., 2013a; Siler et al., 2014a). Taylor (1915) described Luperosaurus com- Species of the genus Pseudogekko represent presicorpus on the basis of one specimen a critical conservation urgency (Alcala et al., collected from Limay, Bataan Province, Lu- 2004; Brown and Diesmos, 2009; Brown et al., zon Island. In this description, Taylor (1915) 2012a); the named taxa are nearly all micro- expressed uncertainty about the placement of endemics threatened by habitat destruction in this species in Luperosaurus (as opposed to the form of anthropogenic forest removal. erecting a new genus to accommodate the one First, all species are arboreal and considered specimen), noting that the new species had an obligate primary forest taxa or Pandanus spp. elongate, compressed body form (a character- (screw pines) plant microhabitat specialists istic generally shared with the other known (Brown and Alcala, 1978). Second, based on species of Luperosaurus; see Brown et al., the little information known about population 2000). Later, Taylor (1922a) transferred this health and microhabitat preferences, popula- species to a novel genus, Pseudogekko, where it tions apparently have decreased over the last remained a monotypic genus until the descrip- 100 yr (IUCN, 2013; Siler et al., 2014a). To tion of a new species, Pseudogekko shebae, make matters worse, the preferred habitat from the Soloman Islands (Brown and Tanner, (lowland and coastal forests) of these species 1949). Unfortunately, the type specimen of P. has been near completely removed from compresicorpus (Philippine Bureau of Science, throughout the Philippines (Catibog-Sinha No. 1781) was destroyed during World War II and Heaney, 2006; Brown and Diesmos, (Brown and Alcala, 1978), which limited 2009; Siler et al., 2014b). Finally, the genus comparisons of this species with other newly has had a complex taxonomic history (Brown described gekkonids from this region. Howev- and Alcala, 1978). Members of Pseudogekko er, the collection of additional specimens of P. previously have been assigned alternatively and compresicorpus from Mindanao and Bohol with little confidence (Taylor, 1922a; Brown

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