First Report on Classical and Molecular Cytogenetics of Doi Inthanon Bent-toed Gecko, Cyrtodactylus inthanon Kunya et al., 2015 (Squamata: Gekkonidae) in Thailand

Abstract

This study analyzed the karyotype of Cyrtodactylus inthanon Kunya et al., 2015 from Doi Inthanon, Chiang Mai Province, northern Thailand. The metaphase and meiotic chromosome preparations were obtained by squash technique from bone marrow and testes, respectively. The chromosomes were stained by Giemsa staining, Ag-NOR banding and molecular cytogenetics with ?uorescence in situ hybridization (FISH) using microsatellites d(CA)₁₅, d(GC)₁₅, d(CAG)₁₀ and d(GAA)₁₀ as probes. The results showed the diploid chromosome number (2n) of 40. The chromosome types of metacentric, submetacentric, acrocentric and telocentric chromosomes were 12-4-2-22, respectively. The Ag-NORs banding technique provides the pair of nucleolar organizer regions (NORs) on the telomeric region of the long arm of acrocentric pair 12. There are no sex differences in karyotypes between males and females. We also found that during metaphase I on meiosis of C. inthanon, the homologous chromosomes appeared synapsis of 20 bivalents. The microsatellite d(CA)₁₅ signals were located on the sub-centromeric region of the metacentric pair 10, whereas the d(GC)₁₅, d(CAG)₁₀ and d(GAA)₁₀ repeats are highly accumulated throughout almost all entire chromosomes. The karyotype formula is as follows: C. inthanon (2n = 40), L^m₂ + L^sm₄ + L^t₆ + M^m₂ + M^t₈ + S^m₈ + S^a₂ + S^t₈.