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.
Highlights
The land snail Cryptozona siamensis, a terrestrial pulmonate gastropod, belongs to the family Ariophantidae [1, 2]
We have reported on the genetic diversity of the 16S rRNA and the c oxidase subunit I (COI) genes, from the C. siamensis samples taken in Thailand
The maximum likelihood tree based on the 16S rRNA and COI fragment sequences of C. siamensis revealed two main clades
Summary
The land snail Cryptozona siamensis, a terrestrial pulmonate gastropod, belongs to the family Ariophantidae [1, 2]. Cryptozona siamensis are important as intermediate hosts that promote the endemicity and transmission of Angiostrongylus cantonensis and A. malaysiensis [3, 5, 6]. The distribution of the land snails accelerates the spread of A. cantonensis [7, 8]. Cryptozona siamensis is native to Thailand, and is regarded as a cosmopolitan species, being one of the most widespread land snails in Southeast Asia [2, 10], with reports of C. siamensis from areas adjacent to Thailand, such as Malaysia, Singapore, and Laos [6, 11, 12]. Cryptozona siamensis has gained attention as an important agricultural and horticultural pest, in India, the United States of America, and Thailand [13, 14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
