 |
| Siamoconus gen. nov. three new species with keeled shells (Siamoconus boreas sp. nov., S. coleus sp. nov., and S. geotrochoides sp. nov.) and one new species with rounded shell (S. destitutus sp. nov.) in Pholyotha, Panha, Sutcharit, Jirapatrasilp, Seesamut, Liew & Tongkerd, 2023. DOI: 10.1071/IS23012 |
Abstract
The Euconulidae is a globally distributed land snail family, but there is no record of this family from Thailand. In this study, we describe a new genus, Siamoconus gen. nov., based on comparative studies of the shell characteristics, external morphology of animals, radula, genital and spermatophore structures, and molecular phylogeny. We performed phylogenetic analyses of two mitochondrial (cytochrome c oxidase I [COI] and 16S rRNA) and one nuclear (28S rRNA) gene fragments to clarify its relationships to other euconulid genera and its position in the superfamily Trochomorphoidea. We also analyzed shell morphometrics, male genitalia, and mantle pigmentation of Siamoconus gen. nov., confirming the status of three new species with keeled shells (S. boreas sp. nov., S. coleus sp. nov., and S. geotrochoides sp. nov.) and one new species with rounded shell (S. destitutus sp. nov.). These new species are restricted to limestone areas in northern and northeastern Thailand. We also reexamined the status of other genera in the superfamily Trochomorphoidea based on shell features, body pigmentation, radula, genital anatomy, spermatophore morphology and a phylogenetic analysis of all available trochomorphoidean DNA sequences. Our analysis suggests that the family Geotrochidae, previously synonymized with the Trochomorphidae, should be resurrected to represent the genus Geotrochus from Borneo, and this family is retrieved as the sister clade of the Dyakiidae.
Keywords: land snail, limestone, Mainland South-East Asia, new genus, new species, phylogeny, systematics, taxonomy.
Arthit Pholyotha, Somsak Panha, Chirasak Sutcharit, Parin Jirapatrasilp, Teerapong Seesamut, Thor-Seng Liew and Piyoros Tongkerd. 2023. Molecular Phylogeny of the Land Snail family Euconulidae in Thailand and Its Position in the Superfamily Trochomorphoidea (Stylommatophora: Limacoidei), with description of A New Genus. Invertebrate Systematics. 37(8); 571-605. DOI: 10.1071/IS23012
