A remarkable new species of the millipede genus Trachyjulus Peters, 1864 (Diplopoda, Spirostreptida, Cambalopsidae) from Thailand, based both on morphological and molecular evidence

Abstract

A new, giant species of Trachyjulus from a cave in southern Thailand is described, illustrated, and compared to morphologically closely related taxa. This new species, T. magnussp. nov., is much larger than all other congeners and looks especially similar to the grossly sympatric T. unciger Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2012, which is widespread in southern Thailand. Phylogenetic trees, both rooted and unrooted, based on a concatenated dataset of the COI and 28S genes of nine species of Cambalopsidae (Trachyjulus, Glyphiulus, and Plusioglyphiulus), strongly support the monophyly of Trachyjulus and a clear-cut divergence between T. magnussp. nov. and T. unciger in revealing very high average p-distances of the COI gene (20.80–23.62%).

Figure 10 from: Srisonchai R, Sutcharit C, Likhitrakarn N (2021) The giant pill-millipede genus Zephronia Gray, 1832 from Thailand, with a redescription of Z. siamensis Hirst, 1907 and descriptions of three new species (Diplopoda, Sphaerotheriida, Zephroniidae). ZooKeys 1067: 19-56. https://doi.org/10.3897/zookeys.1067.72369

“…Recent intense collecting efforts made by Thai specialists in collaboration with the Department of National Parks, Wildlife and Plant Conservation across the country have revealed numerous interesting millipedes, especially in limestone areas. From these efforts, several new genera and numerous new species have been recorded and described (Pimvichai et al 2018(Pimvichai et al , 2020Srisonchai et al 2018a, b, c, d;Likhitrakarn et al 2020Likhitrakarn et al , 2021. The present contribution provides descriptions of three new species of the genus Zephronia, as well as a redescription of Z. siamensis Hirst, 1907 as based both on topotypes and near-topotypes.…”

The Oriental millipede genus Nepalella Shear, 1979, with the description of a new species from Thailand and an updated key (Diplopoda, Chordeumatida, Megalotylidae)

“…Cavernicoly seems to be restricted to the karsts of the southern half of China alone, whereas more to the south, even in the abundant karsts of Thailand or Myanmar, all Nepalella encounters appear to be only epigean and increasingly sporadic (Table 1). Moreover, there seem to be no troglobionts among the Chordeumatida presently known to occur in Thailand or Myanmar, although at least the cave millipede faunas of Thailand and Indochina are quite well studied (e.g., Golovatch 2015;Likhitrakarn et al 2015Likhitrakarn et al , 2016Likhitrakarn et al , 2017Likhitrakarn et al , 2018Likhitrakarn et al , 2020aLikhitrakarn et al , 2020bLikhitrakarn et al , 2021. The most common group, likewise both highly diverse and abundant, that clearly dominates the subterranean millipede faunas of Southeast Asia together with southern China is long known to be the family Cambalopsidae (Spirostreptida) (Golovatch 2015;Likhitrakarn et al 2018Likhitrakarn et al , 2020aLikhitrakarn et al , b, 2021.…”

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

“…The country boasts many unique limestone formations (Naggs et al 2006;Ridd et al 2011;Latinne et al 2013). Thus, Thailand houses many endemic cave-dwelling animals, such as various groups of vertebrates (e.g., Latinne et al 2013;Pauwels et al 2014;Sumontha et al 2017) and invertebrates (e.g., Sedgwick & Schwendinger 1990;Srisonchai et al 2018;Likhitrakarn et al 2020), especially several families of land snails (e.g., Tongkerd et al 2004;Siriboon et al 2014;Dumrongrojwattana & Tanmuangpak 2020;Pholyotha et al 2020bPholyotha et al , 2021Sutcharit et al 2020b). Although the recent studies of karst-associated land snail species in Southeast Asia have flourished, the number of new species discovered has increased every year, supporting that the Thai fauna on limestone karsts, especially land snails, still remains mostly unexplored.…”