Systematic revision of the limestone karst-restricted land snail genus Aenigmatoconcha (Eupulmonata: Helicarionidae), with description of a new species

Abstract

Thai limestone karsts are known to contain a rich biodiversity of animals, especially terrestrial snails, but still require further intensive exploration to evaluate their biodiversity. To date, only a few studies on the limestone karst-inhabiting land snail genera have been published. The present work focuses on the species diversity and phylogenetic relationships of the limestone karst-restricted land snail genus Aenigmatoconcha from Thailand, based on comparative morphology and molecular evidence. The results yielded three known species (A. clivicola Tumpeesuwan & Tumpeesuwan, 2017, A. sumonthai Tumpeesuwan & Tumpeesuwan, 2018, and A. mitis (Pfeiffer, 1863) comb. nov.), plus a new species (A. eunetis Pholyotha & Panha sp. nov). The phylogenetic analyses of partial fragments of the mitochondrial cytochrome oxidase c subunit I (COI) gene confirmed the monophyly of all recognized species and congruence with the traditional morphology-based species designations. Average uncorrected p-distances of COI sequences between species were 9.7–12.0% and within species were 0.2–4.2%. This study also provides the re-description of penial sculpture, penial sheath, flagellum, penial caecum, and mantle lobe morphology that were neglected from the type species description. The present discovery of a new species increases the known diversity of Thai land snails and will support the conservation planning to protect karst biodiversity.

Systematic revision, molecular phylogeny and biogeography of the antlion tribe Acanthoplectrini (Neuroptera: Myrmeleontidae: Dendroleontinae), with emphasis on the Oriental lineage

“…karst plain or karst field), peak cluster, low‐lying land, limestone caves and funnels, which create many habitat heterogeneities at small scales (Y. L. Guo et al, 2018; T. X. Yuan et al, 2014). Karsts are renowned biodiversity hotspots with high levels of endemism, due to the abundance and differentiation of microhabitats, triggering colonization of different ecological niches and species diversification (Clements et al, 2006; Foon et al, 2017; Grismer et al, 2020; Pholyotha et al, 2021; Sutcharit et al, 2020). The high diversity of karst species is particularly evident in some animals with poor dispersal capacity, for example, land snails (Mollusca, Gastropoda) and geckos (Squamata, Gekkonidae), which are highly dependent on limestone (generally for food and shelter) on a narrow geographical scale (Clements et al, 2006; Foon et al, 2017; Grismer et al, 2020; Pholyotha et al, 2021; Schilthuizen et al, 1999).…”

“…Karsts are renowned biodiversity hotspots with high levels of endemism, due to the abundance and differentiation of microhabitats, triggering colonization of different ecological niches and species diversification (Clements et al, 2006; Foon et al, 2017; Grismer et al, 2020; Pholyotha et al, 2021; Sutcharit et al, 2020). The high diversity of karst species is particularly evident in some animals with poor dispersal capacity, for example, land snails (Mollusca, Gastropoda) and geckos (Squamata, Gekkonidae), which are highly dependent on limestone (generally for food and shelter) on a narrow geographical scale (Clements et al, 2006; Foon et al, 2017; Grismer et al, 2020; Pholyotha et al, 2021; Schilthuizen et al, 1999). Most species of Myrmeleontidae are characterized by a fossorial lifestyle of the larvae (Mansell, 1999; Stange, 1994), allowing them to exploit a wide range of microhabitats, including sandy and rocky environments.…”

“…Karsts are renowned biodiversity hotspots with high levels of endemism, due to the abundance and differentiation of microhabitats, triggering colonization of different ecological niches and species diversification (Clements et al, 2006;Foon et al, 2017;Grismer et al, 2020;Pholyotha et al, 2021;Sutcharit et al, 2020). The high diversity of karst species is particularly evident in some animals with poor dispersal capacity, for example, land snails (Mollusca, Gastropoda)…”

“…and geckos (Squamata, Gekkonidae), which are highly dependent on limestone (generally for food and shelter) on a narrow geographical scale (Clements et al, 2006;Foon et al, 2017;Grismer et al, 2020;Pholyotha et al, 2021;Schilthuizen et al, 1999). Most species of Myrmeleontidae are characterized by a fossorial lifestyle of the larvae (Mansell, 1999;Stange, 1994), allowing them to exploit a wide range of (2) female gonocoxites 8 shaped as a pair of digitiform structures.…”

Uncovering local endemism from southeastern Myanmar: description of the new karst-associated terrestrial snail genus Burmochlamys (Eupulmonata, Helicarionidae)

“…Similarly, Chalepotaxis infantilis (Gredler, 1881) and some species of Sophina (i.e., S. tonywhitteni Sutcharit & Panha, 2020) exhibit this smaller tooth but it is very small (Páll-Gergely et al 2016;Sutcharit et al 2020). In contrast, all Aenigmatoconcha species do not have this smaller tooth (Pholyotha et al 2021b). The same modification of radula that present another smaller tooth located behind the larger tooth is recorded in the arboreal land snails, Amimopina macleayi (Brazier, 1876) and Rhachistia histrio (Pfeiffer, 1855), in the family Cerastidae Wenz, 1923(Solem 1973.…”