A new country record of Smooth-backed Gliding Gecko Gekko lionotum (Annandale, 1905) (Squamata: Gekkonidae) from Bangladesh

We report a new record in Bangladesh of the Smooth-backed Gliding Gecko Gekko lionotum Annandale, 1905, recorded from a biodiversity hotspot area at Bandarban located at the southeastern side of the country.  A freshly dead specimen was collected and donated to the Padma Bridge Museum for further identification and display.  We confirmed identification by comparing morphometric and meristic characteristics with literature records.  Gekko lionotum is distributed in Myanmar and northeast India, but was not recorded previously from Bangladesh.  The camouflaging color pattern and cryptic lifestyle of this species, together with and absence of research efforts, likely account for the lack of previous records for this species in Bangladesh territory. 


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Gliding geckos are cryptic species distributed in the tropical forests of southeastern Asia, including southern China (Pawar & Biswas 2001). Among the 60 species of Gekko, four gliding geckos are placed under the subgenus Ptychozoon (Wood et al. 2020), restricted to India, Indonesia, Singapore, the Philippines, and the mainland southeastern Asian countries (Uetz et al. 2020). Although species of this subgenus have been recorded from northeastern India (Pawar & Biswas 2001) and Myanmar (Grismer et al. 2018 We found a freshly dead specimen, later donated to Padma Bridge Museum, Dogachi, Sreenagar, Munshiganj. In the museum this specimen was identified as a Smoothbacked Gliding Gecko Gekko lionotum Annandale, 1905 based on the body features and other morphometric measurements. Considered a rare specimen and a valuable resource for future studies, the gecko was preserved in alcohol as a wet specimen. According to The Reptile Database (www.reptile-database.org/), this species is distributed in India (Mizoram), Myanmar (Rakhine and Bago), Laos, Malaysia, Cambodia, Vietnam, and Thailand.
We combined characters to identify the species after Brown et al. (1997), Brown (1999), and Grismer et al. (2018). The key characters were: snout-vent length 94.8mm; the absence of imbricated scales to support parachute, dorsal tubercles and postorbital stripe; the presence of predigital notch in preantebrachial expansion; 14-15 lamellae in 4 th toe; five caudal lobes fused to form terminal lobe of the tail and denticulated laterally with expansion; absence of caudal tubercles in tail terminus; angling is slight between caudal lobes. We compared these characteristics with other species of the subgenus Ptychozoon (Table 1). The characteristics clearly show the present specimen is G. lionotum.
Morphometric data and coloration: We measured morphometric characteristics using regular slide calipers

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with an accuracy of 0.1mm (Table 2). We compared our morphometric data with the described specimen of Pawar & Biswas (2001). Our comparison matches the description given by Grismer et al. (2018) and the nearest specimen from Mizoram, India (Pawar & Biswas 2001). We also observed the color pattern and body shape of our specimen. The upper parts of the body are gray to dark gray and the underparts are yellowish with black spots (Image 1 & 2). The anterior ventral part is light grayish-yellow and the posterior is dark grayishyellow. Ten transverse, distinct, wavy, blackish-gray
Located in the southeast of the country, Bandarban District is a global biodiversity hotspot of the Indo-Malayan region (Nishat et al. 2002), although the forest vegetation has been degraded by settlers, local inhabitants and others (IRG 2012). We believe that more new species can be found if proper effort is given, however, the richest biodiversity zone also attracts organized poachers to traffic wildlife resources, timber and illegal drugs. The discovery of the lizard species indicates the probability of getting more novel species in this area. We suggest more research work to expand our knowledge and strictly manage the diversity of the zone with the leadership of the Bangladesh Forest Department. www.threatenedtaxa.org The Journal of Threatened Taxa (JoTT) is dedicated to building evidence for conservation globally by publishing peer-reviewed articles online every month at a reasonably rapid rate at www.threatenedtaxa.org. All articles published in JoTT are registered under Creative Commons Attribution 4.0 International License unless otherwise mentioned. JoTT allows allows unrestricted use, reproduction, and distribution of articles in any medium by providing adequate credit to the author(s) and the source of publication.