Karyomorphological delineation, and the NOR loci on the sex chromosome in three species of Chrysopeleinid (Chrysopeleinae: Colubridae) from Thailand

NATTASUDA DONBUNDIT (Biology Program, Faculty of Science, Khon Kaen University. Munag, Khon Kaen 44000, Thailand)
PHICHAYA BAUSRIYOD (Biology Program, Faculty of Science, Khon Kaen University. Munag, Khon Kaen 44000, Thailand)
ALONGKLOD TANOMTONG (Biology Program, Faculty of Science, Khon Kaen University. Munag, Khon Kaen 44000, Thailand)
NATTAPONG SRISAMOOT (Division of Biotechnology, Faculty of Agricultural Technology, Kalasin University. Muang, Kalasin 46000, Thailand)
MONTRI SUMONTHA (Ranong Marine Fisheries Research and Development Station. 157 Chaloem Phrakiat Rd., Paknam, Muang, Ranong 85000, Thailand)
WEERA THONGNETR (Walai Rukhavej Botanical Research Institute, Mahasarakham University. Kantharawichai, Maha Sarakham, Thailand)
ISARA PATAWANG (Department of Biology, Faculty of Science, Chiang Mai University. Muang, Chiang Mai, Thailand)
WEERAYUTH SUPIWONG (Faculty of Interdisciplinary Studies, Nong Khai Campus, Khon Kaen University. Muang, Nong Khai 43000, Thailand)
SUKHONTHIP DITCHAROEN (Division of Biology, Faculty of Science and Technology, Rajamangala University of Technology Thanyaburi. Khlong 6, Khlong Luang, Pathum Thani 12110, Thailand)
NAWARAT MUANGLEN (Department of Fisheries, Faculty of Agricultural Technology, Sakon Nakhon Rajabhat University. Sakon Nakhon 47000, Thailand)
PUNTIVAR KAEWMAD (Major of Biology, Faculty of Science and Technology, Mahasarakham Rajabhat University. Muang, Maha Sarakham 44000, Thailand)

Biodiversitas Journal of Biological Diversity
Vol. 23 No. 7 (2022)

Abstract. Donbundit N, Bausriyod P, Tanomtong A, Srisamoot N, Sumontha M, Thongnetr W, Patawang I, Supiwong W, Ditcharoen S, Muanglen N, Kaewmad P. 2022. Karyomorphological delineation, and the NOR loci on the sex chromosome in three species of Chrysopeleinid (Chrysopeleinae: Colubridae) from Thailand. Biodiversitas 23: 3813-3819. The description of chromosomal characteristics of three snakes from Thailand namely, Ahaetulla fusca, A. prasina, and Chrysopelea ornata was by using conventional staining and Ag-NOR banding techniques. The results showed that the same diploid chromosome number (2n) = 36 (16 macrochromosomes + 20 microchromosomes) and the fundamental number (NF) was 54 while the karyotype formulae in these three species are as follows: A. fusca; 2n(36) = Lm6 + Sm2+ Ssm4 + Sa2+ ZZ/ZW + 20 microchromosomes, A. prasina; 2n(36) = Lm6+ Sm6+ Sa2+ ZZ/ZW + 20 microchromosomes and C. ornata; 2n(36) = Lm4+ Lsm2+ Sm2 + Ssm4+ Sa2+ ZZ/ZW + 20 microchromosomes. Besides, the ZZ/ZW sex chromosome was observed in all species, whereas C. ornata was discovered the heteromorphic sex chromosome for the first time. Nucleolar organizer regions (NORs) are located on telomeric region of one pair in all species, while located on microchromosomes in A. fusca and A. prasina, whereas C. ornata was detected on sex chromosomes. Therefore, the Z chromosome revealed the NOR on the telomeric region of the long arm, while NOR of the W chromosome was located on the telomeric region of the short arm.