Genetic analysis of Cryptozona siamensis (Stylommatophora, Ariophantidae) populations in Thailand using the mitochondrial 16S rRNA and COI sequences

Abstract

Cryptozona siamensis , one of the most widespread land snails, is native to Thailand, and plays a key role as an agricultural pest and intermediate host for Angiostrongylus spp. However, its genetic diversity and population structure has not yet been investigated, and are poorly understood. Therefore, a genetic analysis of the C . siamensis population in Thailand was conducted, based mitochondrial 16S rRNA (402 bp) and COI (602 bp) gene fragment sequences. Cryptozona siamensis randomly collected from 17 locations in four populations across Thailand, between May 2017 and July 2018. Fifty-eight snails were used to examine the phylogeny, genetic diversity, and genetic structure. The maximum likelihood tree based on the 16S rRNA and COI fragment sequences revealed two main clades. A total of 14 haplotypes with 44 nucleotide variable sites were found in the 16S rRNA sequences, while 14 haplotypes with 57 nucleotide variable sites were found in the COI sequences. The genetic diversity of C . siamensis in term of the number of haplotypes and haplotype diversity, was found to be high but the nucleotide diversity showed low levels of genetic differentiation for the COI sequence as also noted with the 16S rRNA sequence. The population genetic structure of C . siamensis revealed genetic difference in most populations in Thailand. However, low genetic difference in some populations may be due to high gene flow. This study provides novel insights into the basic molecular genetics of C . siamensis .

Multigene phylogeny reveals the ribbed shell morphotypes in the land snail genus Sarika (Eupulmonata: Ariophantidae), with description of two new species from Thailand and Myanmar

“…1). Sarika siamensis has a wide distribution, currently known from Thailand, Myanmar, Laos, Malaysia, Singapore, Cambodia, and southern China (Prasankok & Panha, 2011;Abu-Bakar et al, 2014;Tan et al, 2016;Inkhavilay et al, 2019;Boonmachai & Nantarat, 2020;Dumidae et al, 2020;Sutcharit et al, 2020b). Its distribution in Vietnam and other countries needs further studies.…”

“…Naninia [sic] mouhoti: Hemmen & Hemmen, 2001: 45. Cryptozona siamensis: Panha, 1996Hemmen & Hemmen, 2001: 43;Prasankok & Panha, 2011;Abu-Bakar et al, 2014;Tan et al, 2016;Inkhavilay et al, 2019: 75, 76, figs 35a, 56b;Boonmachai & Nantarat, 2020;Dumidae et al, 2020;Sutcharit et al, 2020b: 24, 25, fig. 4d;Pholyotha et al, 2021. Material examined.…”

“…Its distribution in Vietnam and other countries needs further studies. All records of S. siamensis come from sandstone, rocky, limestone, mountainous habitats, and human disturbed areas (Prasankok & Panha, 2011;Tan et al, 2016;Inkhavilay et al, 2019;Boonmachai & Nantarat, 2020;Dumidae et al, 2020;Sutcharit et al, 2020b).…”

“…This species has been classified to the Indian genus Cryptozona since the classification of Panha (1996); however, its generic position has been uncertain. Most studies on this species have concentrated at the population level because this species is the most widespread species in mainland Southeast Asia (Prasankok & Panha, 2011;Tan et al, 2016;Inkhavilay et al, 2019;Boonmachai & Nantarat, 2020;Dumidae et al, 2020;Sutcharit et al, 2020b) and is currently reported as the intermediate host for the rat lungworm that causes eosinophilic meningitis in human (Vitta et al, 2016;Dumidae et al, 2020). There were no records of S. siamensis in Myanmar until our survey in 2016, where a S. siamensis population was discovered in an urban area (Hpa-An City, Myanmar), but we could not find them in suburban or rural areas.…”

Analysis of Genetic Diversity and Structure of Eight Populations of Nerita yoldii along the Coast of China Based on Mitochondrial COI Gene

“…The mitochondrial COI gene has advantages, including high conservatism, a low mutation rate, and maternal inheritance [ 18 , 19 , 20 ]. Consequently, it has emerged as a widely utilized molecular marker in genetic studies of almost all groups of animals, protists, and plants, especially for investigating phylogeny and genealogical geography [ 21 , 22 , 23 , 24 , 25 , 26 , 27 ]. It also has been widely used in Mollusca, such as Ruditapes philippinarum [ 28 ], Haliotis diversicolor [ 29 ], freshwater mussels [ 30 ], and so on.…”