A revision of dragon millipedes II: the new genus Nagaxytes gen. nov., with the description of three new species (Diplopoda, Polydesmida, Paradoxosomatidae)

Abstract

The ‘acantherpestes’ group of dragon millipedes, formerly placed in the genus Desmoxytes Chamberlin, 1923, is revised and assigned to the new genus Nagaxytes Srisonchai, Enghoff & Panha gen. nov. Desmoxytes acantherpestes Golovatch & Enghoff, 1994 is the type species of the new genus and is redescribed as N. acantherpestes (Golovatch & Enghoff, 1994) gen. et comb. nov. Three new species are described from Thailand: N. erecta Srisonchai, Enghoff & Panha gen. et sp. nov. and N. gracilis Srisonchai, Enghoff & Panha gen. et sp. nov. from Kanchanaburi Province, and N. spatula Srisonchai, Enghoff & Panha gen. et sp. nov. from Tak Province. All new species are endemic to western Thailand and all are restricted to limestone habitats. Complete illustrations of external morphological characters, an identification key, and a distribution map are provided.

A revision of dragon millipedes IV: the new genus Spinaxytes, with the description of nine new species (Diplopoda, Polydesmida, Paradoxosomatidae)

“…Based on a comparatively large number of specimens and species of the new genus, our study confirmed that gonopod characters can be used confidently to discriminate the species, just as we found in Desmoxytes and Nagaxytes (Srisonchai et al 2018a, 2018b). Using the gonopods in combination with other morphological characters, such as modification of male femora, sternal lobe between male coxae 4, and number of tubercles/cones/spines on collum and on metaterga, further facilitates reliable taxonomic identification.…”

“…The discovery rate of new dragon millipede species has been increasing in recent years (Liu et al 2014, 2016; Likhitrakarn et al 2015; Golovatch et al 2016; Srisonchai et al 2016, 2018a, 2018b, 2018c). Including the nine new species described here, the diversity of dragon millipedes ( Desmoxytes + Hylomus + Nagaxytes + Gigaxytes + Spinaxytes gen. n.) has now reached 59 species.…”

“…We use morphological terminology according to previous taxonomic publications (Chamberlin 1923; Jeekel 1964, 1980, 2003; Golovatch and Enghoff 1994; Enghoff et al 2007; Golovatch et al 2012; Srisonchai et al 2016, 2018a, 2018b, 2018c. Details of gonopodal terms are shown in the gonopod terminology section below.…”

“…Larvae of ? Leptus have previously been found on species of Desmoxytes ( D.cervina ) and Nagaxytes ( N.acantherpestes (Golovatch & Enghoff, 1994)) (Srisonchai et al 2018a, 2018b, see also Southcott 1992). …”

“…Srisonchai et al (2018a) provided general information on dragon millipedes, split Desmoxytes Chamberlin, 1923, sensu Golovatch and Enghoff (1994) into five genera based on morphological and genetic data, and revised the genus Desmoxytes in its new, restricted sense. Subsequently, Srisonchai et al (2018a, b) described two new genera of dragon millipedes containing several new species and several species transferred from Desmoxytes . In the present study, we describe nine new species constituting the group that we (Srisonchai et al 2018a) provisionally named the ‘ spiny ’ group, of which no species has hitherto been named, and assign them to Spinaxytes gen. n.…”