Abstract
We herein describe a new species of Cyrtodactylus from Kachugaon, in the Kokrajhar District of Assam, India. Morphological characteristics combined with ND2 mitochondrial gene sequence data support its placement within the Cyrtodactylus khasiensis group, identifying Cyrtodactylus raimonaensis sp. nov. as the sister lineage to Cyrtodactylus septentrionalis. It is characterised by a moderate adult size (maximum SVL 71.1 mm), rounded, bluntly conical, and weakly keeled dorsal tubercles arranged in 20 or 21 longitudinal rows, and 36–38 paravertebral tubercles between the axilla and groin. Other diagnostic features include 32–38 mid-ventral scale rows, 13 precloacal pores in male, 13 precloacal pits in females, 17–20 subdigital lamellae beneath the fourth toe, absence of a single row of transversely enlarged subcaudal scales, 7 or 8 pairs of dark dorsal blotches between the axilla and groin, and a tail bearing alternating dark and light bands.
References
- Agarwal, I., Mahony, S., Giri, V.B., Chaitanya, R. & Bauer, A.M. (2018a) Two new species of Cyrtodactylus Gray, 1827 (Squamata: Gekkonidae) with comments on name-bearing types from northeast India. Zootaxa, 4420 (3), 334–356. https://doi.org/10.11646/zootaxa.4420.3.2
- Agarwal, I., Mahony, S., Giri, V.B., Chaitanya, R. & Bauer, A.M. (2018b) Six new Cyrtodactylus (Squamata: Gekkonidae) from northeast India. Zootaxa, 4524 (5), 501–535. https://doi.org/10.11646/zootaxa.4524.5.1
- Bauer, A.M. (2002) Two new species of Cyrtodactylus (Squamata: Gekkonidae) from Myanmar. Proceedings of the California Academy of Sciences, 53 (7), 75–88.
- Bauer, A.M. (2003) Descriptions of seven new Cyrtodactylus (Squamata: Gekkonidae) with a key to the species of Myanmar (Burma). Proceedings of the California Academy of Sciences, 54, 463–498.
- Bharali, M., Thaosen, K., Vabeiryureilai, M., Lalremsanga, H.T., Purkayastha, J., Bhattacharjee, R., Das, M. & Bohra, S. (2026) A new species of Cyrtodactylus Gray, 1827 (Reptilia: Squamata: Gekkonidae) from the montane forests of Dima Hasao District, Assam, India. Journal of Asia-Pacific Biodiversity, 18 (3), 399–410.
- Bhattarai, S., Gautam, B., Neupane, B.P., Khandekar, A., Thackeray, T., Agarwal, I., Tillack, F., Olson, A.R., Hogan, F. & Wright, W. (2025) A review of the genus Cyrtodactylus Gray, 1827 (Squamata: Gekkonidae) of Nepal with descriptions of three new species. Zootaxa, 5594 (3), 401–451. https://doi.org/10.11646/zootaxa.5594.3.1
- Bohra, S.C., Nguyen, T.V., Vogel, G., Lalremsanga, H.T., Biakzuala, L., Das, M., Warjri, H., Thongni, G., Poyarkov, N.A. & Purkayastha, J. (2025) Same but different: A systematic reassessment of the Hebius khasiensis Boulenger, 1890 (Reptilia: Squamata: Natricidae) species complex from the Indo-Burma biodiversity hotspot supports the revalidation of Natrix gilhodesi Wall, 1925 as a valid species. Zootaxa, 5604 (4), 465–504. https://doi.org/10.11646/zootaxa.5604.4.3
- Bohra, S.C., Zonunsanga, H.T., Das, M., Purkayastha, J., Biakzuala, L. & Lalremsanga, H.T. (2022) Morphological and molecular phylogenetic data reveal another new species of bent-toed gecko (Cyrtodactylus Gray: Squamata: Gekkonidae) from Mizoram, India. Journal of Natural History, 56 (41–44), 1585–1608. https://doi.org/10.1080/00222933.2022.2119178
- Boruah, B., Narayanan, S., Aravind, N.A., Lalronunga, S., Deepak, V. & Das, A. (2024) Description of six new species of Cyrtodactylus Gray (Squamata: Gekkonidae) from northeastern India. Vertebrate Zoology, 74, 453–486. https://doi.org/10.3897/vz.74.e124752
- Darevsky, I.S., Helfenberger, N., Orlov, N. & Shah, K. (1998) Two new species of the genus Gonydactylus (Sauria: Gekkonidae) from eastern Nepal. Russian Journal of Herpetology, 4 (2), 89–93. https://doi.org/10.30906/1026-2296-1997-4-2-89-93
- Edgar, R.C. (2004) MUSCLE: multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Research, 32 (5), 1792–1797. https://doi.org/10.1093/nar/gkh340
- Grismer, L.L., Poyarkov, N.A., Quah, E.S.H., Grismer, J.L. & Wood, P.L. Jr. (2022) The biogeography of bent-toed geckos, Cyrtodactylus (Squamata: Gekkonidae). PeerJ, 10, e13153. https://doi.org/10.7717/peerj.13153
- Grismer, L.L., Wood, P.L. Jr., Poyarkov, N.A., Le, M.D., Kraus, F., Agarwal, I., Oliver, P.M., Nguyen, S.N., Nguyen, T.Q., Karunarathna, S., Welton, L.J., Stuart, B.L., Luu, V.Q., Bauer, A.M., O’Connell, K.A., Quah, E.S.H., Chan, K.O., Ziegler, T., Ngo, H., Nazarov, R.A., Aowphol, A., Chomdej, S., Suwannapoom, C., Siler, C.D., Anuar, S. & Grismer, J.L. (2021) Phylogenetic partitioning of the third-largest vertebrate genus in the world, Cyrtodactylus Gray, 1827 (Reptilia; Squamata; Gekkonidae) and its relevance to taxonomy and conservation. Vertebrate Zoology, 71, 101–154. https://doi.org/10.3897/vz.71.e59307
- Grismer, L.L., Wood, P.L. Jr., Quah, E.S.H., Thura, M.K., Herr, M.W. & Lin, A.K. (2019) A new species of forest-dwelling Cyrtodactylus Gray (Squamata: Gekkonidae) from the Indawgyi Wildlife Sanctuary, Kachin State, Myanmar. Zootaxa, 4623 (1), 1–25. https://doi.org/10.11646/zootaxa.4623.1.1
- Grismer, L.L., Wood, P.L. Jr., Thura, M.K., Quah, E.S.H., Murdoch, M.L., Grismer, M.S., Herr, M.W., Lin, A. & Kyaw, H. (2018) Three more new species of Cyrtodactylus (Squamata: Gekkonidae) from the Salween Basin of eastern Myanmar underscore the urgent need for the conservation of karst habitats. Journal of Natural History, 52 (19–20), 1243–1294. https://doi.org/10.1080/00222933.2018.1449911
- Jerdon, T.C. (1870) Notes on Indian herpetology. Proceedings of the Asiatic Society Bengal, March 1870, 66–85.
- Kalyaanamoorthy, S., Minh, B.Q., Wong, T.K., von Haeseler, A. & Jermiin, L.S. (2017) ModelFinder: fast model selection for accurate phylogenetic estimates. Nature Methods, 14, 587–589. https://doi.org/10.1038/nmeth.4285
- Kamei, R.G. & Mahony, S. (2021) A new species of bent-toed gecko (Squamata: Gekkonidae: Cyrtodactylus Gray, 1827) from the Garo Hills, Meghalaya State, north-east India, and discussion of morphological variation for C. urbanus. Herpetological Journal, 31 (3), 177–196. https://doi.org/10.33256/31.3.177196
- Kumar, S., Stecher, G. & Tamura, K. (2016) MEGA7: molecular evolutionary genetics analysis version 7.0 for bigger datasets. Molecular Biology and Evolution, 33 (7), 1870–1874. https://doi.org/10.1093/molbev/msw054
- Lalremsanga, H.T., Chinliansiama, H., Bohra, S.C., Biakzuala, L., Vabeiryureilai, M., Muansanga, L., Malsawmdawngliana, F., Hmar, G.Z., Decemson, H.T., Siammawii, V., Das, M. & Purkayastha, J. (2022) A new bent-toed gecko (Cyrtodactylus Gray: Squamata: Gekkonidae) from the state of Mizoram, India. Zootaxa, 5093 (4), 465–482. https://doi.org/10.11646/zootaxa.5093.4.5
- Lalremsanga, H.T., Colney, Z., Vabeiryureilai, M., Malsawmdawngliana, F., Bohra, S.C., Biakzuala, L., Muansanga, L., Das, M. & Purkayastha, J. (2023) It’s all in the name: another new Cyrtodactylus Gray (Squamata: Gekkonidae) from northern Mizoram, north-east India. Zootaxa, 5369 (4), 553–575. https://doi.org/10.11646/zootaxa.5369.4.5
- Lanfear, R., Frandsen, P.B., Wright, A.M., Senfeld, T. & Calcott, B. (2017) PartitionFinder 2: new methods for selecting partitioned models of evolution for molecular and morphological phylogenetic analyses. Molecular Biology and Evolution, 34 (3), 772–773. https://doi.org/10.1093/molbev/msw260
- Li, P.P. (2007) Description of a new subspecies of Cyrtodactylus khasiensis from China. Acta Zootaxonomica Sinica, 32, 733–737.
- Liu, S. & Rao, D. (2021) A new species of Cyrtodactylus Gray, 1827 (Squamata: Gekkonidae) from western Yunnan, China. Journal of Natural History, 55, 713–731. https://doi.org/10.1080/00222933.2021.1921871
- Macey, J.R., Larson, A., Ananjeva, N.B., Fang, Z. & Papenfuss, T.J. (1997) Two novel gene orders and the role of light-strand replication in rearrangement of the vertebrate mitochondrial genome. Molecular Biology and Evolution, 14, 91–104. https://doi.org/10.1093/oxfordjournals.molbev.a025706
- Mahony, S. & Kamei, R.G. (2021) A new species of Cyrtodactylus Gray (Squamata: Gekkonidae) from Manipur State, northeast India, with a critical review highlighting extensive errors in literature covering bent-toed geckos of the Indo-Burma region. Journal of Natural History, 55 (39–40), 2445–2480. https://doi.org/10.1080/00222933.2021.1994667
- Mahony, S. (2009) Taxonomic status of Cyrtodactylus khasiensis tamaiensis (Smith, 1940) and description of a new species allied to Cyrtodactylus chrysopylos Bauer, 2003 from Myanmar (Reptilia: Gekkonidae). Hamadryad, 34 (1), 62–74.
- Minh, B.Q., Nguyen, M.A.T. & von Haeseler, A. (2013) Ultrafast approximation for phylogenetic bootstrap. Molecular Biology and Evolution, 30 (5), 1188–1195. https://doi.org/10.1093/molbev/mst024
- Mirza, Z.A., Bhosale, H., Ansari, F., Phansalkar, P., Sawant, M., Gowande, G. & Patel, H. (2021) A new species of geckos of the genus Cyrtodactylus Gray, 1827 from Arunachal Pradesh, India. Evolutionary Systematics, 5, 13–23. https://doi.org/10.3897/evolsyst.5.61667
- Mirza, Z.A., Bhosale, H.S., Thackeray, T., Phansalkar, P., Sawant, M., Gowande, G.G. & Patel, H. (2022) A new species of bent-toed geckos of the genus Cyrtodactylus Gray, 1827 from western Arunachal Pradesh, India. Herpetozoa, 35, 65–76. https://doi.org/10.3897/herpetozoa.35.e80610
- Nguyen, L.T., Schmidt, H.A., von Haeseler, A. & Minh, B.Q. (2015) IQ-TREE: a fast and effective stochastic algorithm for estimating maximum-likelihood phylogenies. Molecular Biology and Evolution, 32 (1), 268–274. https://doi.org/10.1093/molbev/msu300
- Purkayastha, J., Das, M., Bohra, S.C., Bauer, A.M. & Agarwal, I. (2020) Another new Cyrtodactylus (Squamata: Gekkonidae) from Guwahati, Assam, India. Zootaxa, 4732 (3), 375–392. https://doi.org/10.11646/zootaxa.4732.3.2
- Purkayastha, J., Lalremsanga, H.T., Bohra, S.C., Biakzuala, L., Decemson, H.T., Muansanga, L., Vabeiryureilai, M., Chauhan, S. & Rathee, Y.S. (2021) Four new bent-toed geckos (Cyrtodactylus Gray: Squamata: Gekkonidae) from northeast India. Zootaxa, 4980 (1), 451–489. https://doi.org/10.11646/zootaxa.4980.3.2
- Purkayastha, J., Lalremsanga, H.T., Litho, B., Rathee, Y.S., Bohra, S.C., Vabeiryureilai, M., Biakzuala, L. & Muansanga, L. (2022) Two new Cyrtodactylus (Squamata, Gekkonidae) from Northeast India. European Journal of Taxonomy, 794, 111–139. https://doi.org/10.5852/ejt.2022.794.1659
- Tamura, K. & Nei, M. (1993) Estimation of the number of nucleotide substitutions in the control region of mitochondrial DNA in humans and chimpanzees. Molecular Biology and Evolution, 10, 512–526. https://doi.org/10.1093/oxfordjournals.molbev.a040023
- Tamura, K., Stecher, G. & Kumar, S. (2021) MEGA11: Molecular Evolutionary Genetics Analysis version 11. Molecular Biology and Evolution, 38 (8), 3022–3027. https://doi.org/10.1093/molbev/msab120
- Uetz, P., Freed, P. & Hošek, J. (2025) The reptile database. Available from: http://www.reptiledatabase.org (accessed 22 July 2025)
