The taxonomy and phylogeny of the Cyrtodactylus brevipalmatus group (Squamata: Gekkonidae) with emphasis on C. interdigitalis and C. ngati

Abstract Convergent morphological specializations for an arboreal lifestyle in most species of the Cyrtodactylus brevipalmatus group have been a confounding factor for establishing a stable taxonomy among its species. Recent references to C. interdigitalis from throughout Thailand and Laos were made without comparisons to the type material from Tham Yai Nam Nao, Nam Nao National Park, Phetchabun Province, Thailand, but instead, were based on general morphological similarity and distribution. The taxonomy of C. interdigitalis is stabilized here by comparing the paratypes to other specimens from Thailand and Laos and recovering their phylogenetic relationships based on newly acquired genetic data, including those from the type locality. The phylogeny recovered all specimens outside the type locality to be either C. ngati from Vietnam or new species closely related to C. ngati. Cyrtodactylus interdigitalis is shown here to be a range-restricted upland endemic on the Phetchabun massif of northern Thailand. The phylogeny also indicates that C. ngati extends hundreds of kilometers farther south into northern Thailand and central Laos. We hypothesize that the significant morphological divergence in body shape of the types of C. ngati, compared to that of the Lao and Thai populations, may be due to local adaptions for utilizing karst (C. ngati) rather than vegetation (Lao and Thai populations). Additionally, phylogenetic and multivariate analyses identified a potentially new species from Phu Hin Rong Kla National Park, Phitsanulok Province, in northern Thailand and another from the Khlong Naka Wildlife Sanctuary, Ranong Province, in southern Thailand. A series of newly examined specimens from Kaeng Krachan National Park, Phetchaburi Province, Thailand represents a possible ~82 km range extension to the southeast of C. rukhadeva. This research continues to underscore the high diversity of range-restricted upland endemics in Thailand and the importance of examining type material (if possible) in the context of a phylogeny so as to construct proper taxonomies that reveal, rather than obscure, diversity

A novel approach to state bounding for discrete-time Markovian jump systems with interval time-varying delay

This paper concerns with the problem of state bounding for a class of discrete-time Markovian jump systems with interval time-varying delay. By constructing a new Lyapunov–Krasovskii functional combining with the delay-decomposition technique and the reciprocally convex approach, new delay-range-dependent conditions are derived ensuring that all state trajectories of the system are mean square bounded. These conditions are derived in terms of matrix inequalities which can be computationallysolved to find a smallest possible bound of mean square. A numerical example is provided to verify the effectiveness of the obtained result

First Record of Philautus petilus Stuart and Heatwole, 2004 (Amphibia: Anura: Rhacophoridae) from Vietnam and Its Phylogenetic Position

A small rhacophorid, Philautus petilus known from only the female holotype, is recorded for the first time outside of the type locality in Laos. Three specimens, containing the first known males of the species, were collected from Muong Nhe Nature Reserve in Dien Bien Province, northwestern Vietnam. The Vietnamese specimens are identified as P. petilus based on morphological similarities with the holotype from Laos. In addition, our molecular data verify the transfer of this species from Philautus to the genus Theloderma

Fig. 2 in Two additional records of megophryid frogs, Leptobrachium masatakasatoi Matsui, 2013 and Leptolalax minimus (Taylor, 1962), for the herpetofauna of Vietnam

Fig. 2. Leptobrachium masatakasatoi from Son La Province, Vietnam (TBU PAE.365, adult male). (a) dorsolateral view. (b) Ventral view. Photos A.V. Pham

New provincial records of skinks (Squamata: Scincidae) from northwestern Vietnam.

We report six new records of skinks from northwestern Vietnam: Eutropis macularius, Scincelladevorator , S.monticola, S.ochracea, Sphenomorphuscryptotis and S.indicus. Our new findings increase the species number of skinks (Scincidae) to nine in Dien Bien Province and to 14 in Son La Province. We also provide additional natural history data of aforementioned species

New provincial records of skinks (Squamata: Scincidae) from northwestern Vietnam.

We report six new records of skinks from northwestern Vietnam: Eutropis macularius, Scincelladevorator , S.monticola, S.ochracea, Sphenomorphuscryptotis and S.indicus. Our new findings increase the species number of skinks (Scincidae) to nine in Dien Bien Province and to 14 in Son La Province. We also provide additional natural history data of aforementioned species

Cyrtodactylus ngati Le & Sitthivong & Tran & Grismer & Nguyen & Le & Ziegler & Luu 2021, sp. nov.

Cyrtodactylus ngati sp. nov. (Figs. 2–3) Holotype. HNUE-R00111 (Field number PT.2017.215), adult male, collected on 17 August 2017 by D. T. Le, D. T. Truong, H.Q. Nguyen, N.H. Nguyen, and A.N. Nguyen, in the karst forest near Pa Thom Cave, Pa Xa Lao Village, Pa Thom Commune, Dien Bien District, Dien Bien Province, Vietnam (21°17’N; 102°54’E, 695 m a.s.l.). Paratypes. IEBR 4829 (Field number PT.2016.07), adult female, VNUF R.2020.12 (Field number PT.2016.06), adult female, collected on 27 August 2016; HNUE-R00112 (Field number PT.2017.187), subadult female, collected on August 2017, the same data as the holotype. Diagnosis. The new Cyrtodactylus species can be distinguished from remaining congeners by the following combination of morphological characters: maximum SVL 69.3 mm; dorsal pattern consisting of six dark irregular transverse bands between limb insertions; intersupranasal single; dorsal tubercles present on occiput, body, hind limbs and on first half of tail; 17–22 irregular dorsal tubercle rows at midbody; lateral folds clearly defined, with interspersed tubercles; 32–38 ventral scales between ventrolateral folds; 13 precloacal pores separated by a diastema of 5/5 poreless scales from 7/7 femoral pores in enlarged femoral scales; precloacal and femoral pores absent in females; 1–3 postcloacal tubercles on each side; median subcaudal scales not transversely enlarged. Description of holotype. Adult male, SVL 66.5 mm; body elongate (TrunkL/SVL 0.43); head elongate (HL/ SVL 0.30), relatively wide (HW/HL 0.62), depressed (HH/HL 0.36), distinguished from neck; loreal region concave; snout long (SE/HL 0.37), obtuse anteriorly, longer than diameter of orbit (OD/SE 0.50); scales on snout small, round or oval, granular, bigger than those in frontal and parietal regions; orbit large (OD/HL 0.19), pupils vertical; supraciliaries with spinous scales posteriorly; ear oval-shaped, small (EarL/HL 0.03); rostral wider than high with a straight medial suture, bordered with first supralabial and nostril on each side; supranasals in contact with each other; nostril opening oval, surrounded by supranasal, rostral, first supralabial, and two enlarged postnasals; mental triangular, slightly wider than long (ML/MW 0.68); two enlarged postmentals; 10/9 supralabials; 8/9 infralabials; dorsal scales granular; dorsal tubercles round, conical, present from occipital region to dorsum and half of tail, tubercles in 18 irregular rows at midbody, larger at midbody, each surrounded by nine granular scales; ventrolateral body folds well defined, with interspersed tubercles; ventral scales smooth, round, midventral scales three times larger than the granules on dorsum, 38 longitudinal ventral scale rows at midbody; gular region with homogeneous, small and smooth scales; 168 ventral scales from mental to cloacal slit; precloacal groove absent; enlarged precloacal scales present; 13 contiguous precloacal pores, separated by 5/5 poreless scales and 7/7 femoral pores (FPl+PP+FPr: 7+13+7); enlarged precloacal and femoral scales present. Fore- and hind limbs moderately slender (ForeL/SVL 0.13, CrusL/SVL 0.16); enlarged tubercles on dorsal surface of forelimbs absent, but covered with slightly enlarged granules; hind limbs with distinctly developed tubercles dorsally; fingers and toes basally webbed; 16/16 lamellae under fourth finger; 12/13 lamellae under fourth toe. Tail longer than SVL (TaL 74.1 mm); 3/2 postcloacal tubercles; dorsal surface of tail bearing distinct tubercles on anterior one-half of tail; lateral rows of spinose scales present; median subcaudal scales slightly enlarged, flat, smooth. ......continued on the next page ......continued on the next page ......continued on the next page ......continued on the next page Coloration in life. Background coloration light yellowish brown, with dark brown dorsal pattern; dorsal surface of head with irregular dark brown blotches; an irregularly shaped dark nuchal loop present, edged in dark brown, butterfly-shaped; six dark transversal bands between limb insertions, somewhat irregularly shaped, somewhat muted in color; tubercles at midbody greyish brown; dorsal surface of limbs with dark spots; dorsal surface of original tail dark grey with light bands, and dark narrow ring within the latter; ventral surface of head, body and limbs cream; subcaudal region dark grey with light bands (see Fig. 2). Sexual dimorphism and variation. The females differ from males by the absence of hemipenial swellings at the tail base as well as femoral and precloacal pores. For further morphological characters of the paratypes see Table 2 and Fig. 4. Comparisons. We compared Cyrtodactylus ngati sp. nov. with other congeners from Vietnam and neighboring countries in the mainland Indochina region, including Laos, Cambodia, and Thailand based on examination of specimens (see Appendix) and data from literature (Luu et al. 2014; Nazarov et al. 2014; Nguyen et al. 2014; Panitvong et al. 2014; Pauwels et al. 2014; Pauwels & Sumontha 2014; Schneider et al. 2014 a,b; Nurngsomsri et al. 2014; Grismer et al. 2015; Luu et al. 2015; Sumontha et al. 2015; Pauwels et al. 2016; Le et al. 2016; Luu et al. 2016a,b,c, 2017; Nguyen et al. 2017; Chuaynkern et al. 2018; Pauwels et al. 2018; Nazarov et al. 2018; Murdoch et al. 2019; Pham et al. 2019; Sitthivong et al. 2019; Schneider et al. 2020; Ostrowski et al. 2020, 2021). The new species can be differentiated from other known species of the genus Cyrtodactylus by morphological characters (see Table 3). Below we compared the new species with the Cyrtodactylus brevipalmatus group data obtained from Smith (1923); Dring (1979); Ulber (1993); Nurngsomsri et al. (2014); and Chuaynkern et al. (2018). In comparison with the species from the brevipalmatus group, comprising C. interdigitalis Ulber, C. elok Dring, and C. brevipalmatus (Smith), the new species can be distinguished from C. interdigitalis by its smaller size (maximum SVL 69.3 mm versus 80.0 mm), having fewer precloacal pores (13 versus 14–16), more body bands (6 versus 3), the absence of tubercles on forelimbs (versus present), the presence of dark narrow ring in each light tail band (versus absent), and the presence of slightly enlarged subcaudal scales (versus absent); from C. elok by its smaller size (maximum SVL 69.3 mm versus 83.0 mm), having fewer ventral scales (32–38 versus 52), more body bands (6 versus 3), more precloacal pores in males (13 versus 8), the presence of enlarged femoral scales and femoral pores in males (versus absent), and the presence of slightly enlarged subcaudal scales (versus absent); from C. brevipalmatus by having more femoral pores in males (13 versus 9 or 10), more body bands (6 versus 3), the absence of precloacal pores in females (versus present), and dorsal pattern banded (versus blotched). For more details see Table 4. Distribution. Cyrtodactylus ngati sp. nov. is currently known only from the type locality in Dien Bien Province, Vietnam (Fig. 4). Etymology. We name this new species in honor of our colleague, Assoc. Prof. Dr. Ngat Nguyen Le, Hanoi National University of Education, Vietnam, in recognition of his contribution to herpetological research in Vietnam. As common names, we suggest Ngat’s Bent-toed Gecko (English) and Thằn lằn ngón ngật (Vietnamese). Ecological notes. Specimens were found between 19:00 and 21:00, on limestone cliffs and in rock crevices, approximately 1–2 m above the ground. The surrounding habitat was disturbed evergreen forest of small hardwoods and shrubs on the mountain slope. The humidity was approximately 74–76% and the air temperature ranged from 23 to 26 oC (Fig. 5). All other members of the Cyrtodactylus brevipalmatus group are arboreal, have prehensile tails carried above their back in a coiled position, and usually are found only on vegetation (Grismer et al. 2020). This is the first member of the group that apparently lacks a prehensile tail and occurs on karst. Grismer et al. (2020) demonstrated that an arboreal habitat preference was the ancestral condition for the C. brevipalmatus group and these findings represent tthe first record of a potential transition of an arboreal habitat to a karst habitat preference in Cyrtodactylus.Published as part of Le, Dzung Trung, Sitthivong, Saly, Tran, Tung Thanh, Grismer, L. Lee, Nguyen, Truong Quang, Le, Minh Duc, Ziegler, Thomas & Luu, Vinh Quang, 2021, First record of the Cyrtodactylus brevipalmatus group (Squamata: Gekkonidae) from Vietnam with description of a new species, pp. 492-510 in Zootaxa 4969 (3) on pages 495-505, DOI: 10.11646/zootaxa.4969.3.3, http://zenodo.org/record/475141

First record of the Cyrtodactylus brevipalmatus group (Squamata: Gekkonidae) from Vietnam with description of a new species

A new species of the genus Cyrtodactylus is described from Dien Bien Province, northwestern Vietnam based on morphological and molecular data. Cyrtodactylus ngati sp. nov. can be distinguished from remaining congeners by the following combination of characters: maximum SVL 69.3 mm; dorsal pattern consisting of six dark irregular transverse bands between limb insertions: inter-supranasals one; dorsal tubercles present on occiput, body, hind limbs and on first half of tail; 17-22 irregular dorsal tubercle rows at midbody; lateral folds clearly defined, with interspersed tubercles; 32-38 ventral scales between ventrolatcral folds; 13 precloacal pores separated by a diastema of 5/5 poreless scales from a series of 7/7 femoral pores in enlarged femoral scales; precloacal and femoral pores absent in females; 1-3 postcloacal tubercles on each side; transversely enlarged median subcaudal scales absent. In the molecular analyses, the new species is shown to be the sister taxon to C. interdigitalis from Thailand. This is the 47th species of the genus Cyrtodactylus and the first member of the C. brevipalmatus species group recorded from Vietnam