Molecular Phylogeny Reveals a New Snorkel Snail, Rhiostoma panhai sp. nov., from Thailand (Gastropoda: Caenogastropoda: Cyclophoridae)


  • Pongpun Prasankok School of Biology, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000, THAILAND


DNA barcoding, mitochondrial DNA, operculate land snail, taxonomy


The present study used two mitochondrial gene fragments (COI and 16S rRNA) and morphology to reveal a new species of Rhiostoma in Thailand: Rhiostoma panhai sp. nov. Genetic divergence between the new species and other Rhiostoma species was high, ranged from 14 to 19% p-distance. Phylogenetic analyses confirmed the novelty of this new species. The new species differs from other Rhiostoma species by having a detached whorl shorter than the aperture width (mean detached-whorl length/aperture width: 0.89±1.40), a small, curved, and slender tubular breathing device, and dark brown with paler zigzag streaks periostracum.


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How to Cite

Prasankok, P. 2023. Molecular Phylogeny Reveals a New Snorkel Snail, Rhiostoma panhai sp. nov., from Thailand (Gastropoda: Caenogastropoda: Cyclophoridae). Tropical Natural History. 7 (Sep. 2023), 251–259.



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