First Cytogenetic Study of Puff-Faced Water Snake, <i>Homalopsis buccata</i> (Squamata, Colubridae) by Conventional Staining, Ag-NOR Banding and GTG-Banding Techniques

Abstract

SummaryThe first cytogenetics of the puff-faced water snake (Homalopsis buccata) from Khon Kaen Province, Thailand was obtained from the present study. Mitotic chromosome was prepared directly from the spleens of specimens after in vivo colchicines treatment. The metaphase spreads were performed on microscopic slides and air-dried. Conventional staining, Ag-NOR banding, and GTG-banding techniques were applied to stain the chromosome with Giemsa s solution. Results showed that the number of diploid chromosome was 2n=36, while the fundamental number (NF) was 52 in both males and females. The types of macrochromosome were four large metacentric, two medium metacentric, six small metacentric, and two small acrocentric chromosome, and 20 microchromosomes. It was found that nucleolar organizer regions (NORs, the representative of chromosome marker) locate on the long arms near centromeres of a pair of microchromosomes, pair 15. The Z chromosome was a small metacentric chromosome, while the W chromosome was a small submetacentric chromosome. From the GTG-banding technique, it was found that each chromosome pairs could be clearly differentiated and the numbers of bands in the H. buccata was 109. The karyotype formula is as follows:2n (

Karyotypes of Six Species of Colubrid Snakes from the Western Hemisphere, and the 140-Million-Year-Old Ancestral Karyotype of Serpentes

“…Nevertheless, Ota (1999) found in Pareas iwasakii (representing the related family Pareatidae) the same basic karyotype as occurs in Lampropeltis triangulum, and it was also found in 41 out of 43 species of the Viperidae, representing diverse genera from several continents (see literature review by Cole, 1990). The same basic karyotype was also found in Homalopsis buccata by Pinthong et al (2013). Deviations from this ancestral karyotype, as in Oxybelis aeneus reported here and in North American natricines (Baker et al, 1972;Eberle, 1972) Bianchi et al, 1969;De Smet, 1978) and Eunectes murinus (see De Smet, 1978) have karyotypes extremely similar to those of Xenopeltis unicolor ( fig.…”

Why Do Some Vertebrates Have Microchromosomes?

“…This high variation is arguably driven by dynamic repeated fusion of macro- and microchromosomes. Furthermore, certain squamate reptiles may harbor very few or no dot-shaped microchromosomes, for example, in lacertid lizards (Lacertidae) and geckos (Gekkonidae) [ 56 , 58 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 ], whereas other squamates can carry as many as 36 microchromosomes [ 99 ]. The most common chromosome number in snakes is 2 n = 36, comprising 16 macrochromosomes and 20 microchromosomes, while worm lizards show a large variation in chromosome number (2 n = 30–50) [ 88 , 100 ].…”

Cytogenetic of Skink (Reptilia, Scincidae) from Thailand: II: Chromosome Analyses of Stripe Tree Skink (<i>Lipinia vittigera</i>)

“…For L. vittigera, we found a diploid chromosome number of 2n=28 in all studied samples, of which 16 pairs were macrochromosomes and 12 pairs were microchromosomes. The chromosomes of some reptile groups are highly variable in terms of size and morphology, and are characterized by bimodal or asymmetric karyotypes composed of macrochromosomes and microchromosomes (Pinthong et al 2013, Siripiyasing et al 2013.…”