First record of the recently described Cyrtodactylus tripuraensis Agarwal , Mahony , Giri , Chaitanya & Bauer , 2018 ( Squamata , Gekkonidae ) in Bangladesh

Cyrtodactylus tripuraensis (Agarwal, Mahony, Giri, Chaitanya & Bauer, 2018) was recently described from Tripura state of northeast India. In June 2018, we found a subadult and an adult male individual in Lawachara National Park, ‎Maulvibazar District, Sylhet Division, Bangladesh. We identify the individuals as C. tripuraensis based on morphological study. Though the new locality of C. tripuraensis is approximately only 40 km away from the nearest locality in Tripura state, India, this is the first record of this species in Bangladesh.


Introduction
Cyrtodactylus is the most species-rich genus of geckos in the world, which commonly known as Bent-toed geckos.More than half of the species of this genus have been described in the last decade (Grismer et al. 2012, 2014, Uetz 2017).Cyrtodactylus is geographically wide-ranging and occupies diverse ecological niches.This genus is distributed eastwards throughout Southeast Asia and the Indo-Australian Archipelago, reaching the Philippines, New Guinea, northern Australia, and the Solomon Islands (Rösler et al. 2007, Uetz 2017, Wood et al. 2012, Mahony 2009, Grismer et al. 2014).Approximately 8 species of this genus are known from neighboring countries of Bangladesh (Agarwal et al. 2018a (Ahsan 1998, Khan 2004).Then Mahony et al. (2009) concluded that C. khasiensis recorded from Bangladesh is actually C. ayeyarwadyensis Bauer, 2003.In this sense, only C. ayeyarwadyensis is recorded from Bangladesh.Cyrtodactylus ayeyarwadyensis is considered to occur in the hilly areas of the northeast, east and southeast forested regions in the country (Hasan et al. 2014, Khan 2015).In this study, we collected 2 specimens from Lawachara National Park, which is situated in northeast Bangladesh and described the morphological characteristics.All the morphological characteristics are similar with the recently described C. tripuraensis, which provides the first known occurrences of C. tripuraensis in Bangladesh.

Methods
We collected 2 individuals (1 adult male and 1 juvenile) from Lawachara National Park during our regular night survey of Bengal Slow Loris (Nycticebus bengalensis Lacépède, 1800).Lawachara National Park is a semi ever-green forest situated in the North-east region of Bangladesh.Specimens were collected by hand and photographed.Subsequently they were euthanized, preserved in 10% formalin, later transferred to 70% alcohol, and deposited in the collection of the Department of Zoology, Jagannath University, Dhaka.We used a dissecting microscope to examine the preserved specimens.Morphometric measurements of adult individual were made with digital calipers (nearest 0.01 mm) following Agarwal et al. (2018b).The specimens were identified using the original species descriptions (Agarwal et al. 2018b).We also compared these specimens with C. ayeyarwadyensis collected from Bangladesh and C. khasiensis (Mahony 2009, Mahony et al. 2009).
Identification.Collected specimens are identified as C. tripuraensis based on the following characters: the snoutvent length of adult male is 66 mm; tail length is 61 mm and trunk length is 34 mm; head is longer (17 mm) than width (11 mm) and head height is 7 mm; 1 pair of elongated postmental scale situated behind the large mental scale (Fig. 1); 20 rows of circular tubercles present at mid-dorsum, 35 rows of mid-body ventral scales and 52 paravertebral tubercles present; specimen has 34 precloacofemoral pores in a single series without precloacal groove.This specimen is different from C. ayeyarwadyensis and C. khasiensis based on the difference in number of precloacal and precloacofemoral pores.Cyrtodactlyus khasiensis has 10-12 precloacal pores and C. ayeyarwadyensis has 10-28 precloacofemoral pores.
Habitat.The first specimen (subadult JnUZool-R0318) was collected from a damp and mossy trunk of Lophopetalum fimbriatum Wight, 1840 about 0.5 m from the ground.Another individual (adult male JnUZool-R0418) was collected from a hollow in a damp and mossy old brick wall 1.25 m from the ground.

Discussion
Cyrtodactylus tripuraensis is a recently described species of bent-toed gecko from Tripura state of India (Agarwal et al. 2018b).Agarwal et al. (2018b) predicted C. tripuraensis should be found in neighboring regions of eastern and southeastern Bangladesh, and southern Assam (e.g., Karimganj district) in India.Lawachara National Park is situated in Sreemongal district, which is adjacent to the state of Tripura, India.The nearest locality of C. tripuraensis in Rowa Wildlife Sanctuary is approximately 40 km from Lawachara National Park.Other known localities are not so far from the new locality, Lawachara National Park is 87 km away from Sepahijala Wildlife Sanctuary, 88 km from Chobimura and 99 km from Gumti.Habitat type of the collected holotype and paratypes are also similar to the habitat of Lawachara National Park.Agarwal et al. (2018b) found all individuals from 29 to 56 m elevation from the sea level.We found our specimens at 56 m elevation from sea level.This elevation is almost similar to the previous locality of C. tripuraensis.Southeastern Bangladesh populations and northern most Bangladesh population are considered as C. ayeyarwadyensis (Mahony et al. 2009).These populations are not far from the locality of C. tripuraensis (Table 1), including the population from Kaptaimukh Beat, which is located 100 km south of Gumti Wildlife Sanctuary in the same continuous north-south running valley.Agarwal et al. (2018b) recommended conducting further molecular studies on these southeastern populations for confirmation of taxonomic affinity in light of the morphologically similar species C. tripuraensis.A molecular study is also needed for our study, but was not possible for us.So, we conducted a morphological study and confirmed the specimen as C. tripuraensis.

Figure 1 .
Figure 1.Cyrtodactylus tripuraensis.A. Dorsal view of specimens.B. Ventral view of specimens C. Circular tubercles on the dorsal side of the body.D. Scale pattern of the ventral side of the head.

Figure 2 .
Figure 2. Map showing the previous and present localities of Cyrtodactylus tripuraensis.
).Recently Agarwal et al. (2018b) described 2 new species from West Ben-gal state (Cyrtodactylus bhupathyi) and Tripura state (C.tripuraensis) of India.Though the distributions of these species are closer to Bangladesh, only 2 species of Cyrtodactylus have been recorded here.At first, only C. khasiensis Jerdon, 1870 was reported from Bangladesh