Hylomus Cook & Loomis, 1924

Srisonchai, Ruttapon, Enghoff, Henrik, Likhitrakarn, Natdanai & Panha, Somsak, 2018, A revision of dragon millipedes I: genus Desmoxytes Chamberlin, 1923, with the description of eight new species (Diplopoda, Polydesmida, Paradoxosomatidae), ZooKeys 761, pp. 1-177 : 1

Genus Hylomus Cook & Loomis, 1924 stat. rev.

Hylomus Cook & Loomis, 1924: 105

Notes.

Hylomus was established as a monotypic genus by Cook and Loomis (1924), who were so impressed by the remarkable external features of the type species, H. draco Cook & Loomis, 1924, viz., the strongly elevated paraterga (like trees), that they placed the new species not only in a new genus but even in a new family, Hylomidae .

Jeekel (1964, 1968) maintained Hylomus as a valid genus, including only H. draco , and moved it into family Paradoxosomatidae , stating that the genus Pratinus Attems, 1937 (= Desmoxytes ) was closely related to Hylomus .

Later, Jeekel (1980a) re-assessed the generic allocation of all members of Hylomus , Desmoxytes Chamberlin, 1923, Pratinus Attems, 1937, Prionopeltis Pocock, 1895 and Ceylonesmus Chamberlin, 1941, leading to the recognition of three genera: Hylomus , Desmoxytes (= Prionopeltis , Pratinus , Ceylonesmus ) and Pteroxytes Jeekel, 1980. Jeekel (1980a) stated that the morphological characters of Hylomus showed clear differences from Desmoxytes and Pteroxytes (paranota antler-shaped and detail of gonopodal apex). The same author emphasised that his work was just a preliminary outline, and that "the discovery of new species … may considerably change the picture".

Golovatch and Enghoff (1994) disagreed with Jeekel’s idea (1980a) to maintain Hylomus and Pteroxytes as separate genera. Based on new evidence from examination of old and new material, previous literature and the first cladistic analysis based on morphology, the authors synonymised Hylomus and Pteroxytes under Desmoxytes and assigned the genus to tribe Orthomorphini , of which they regarded Hylomini a synonym.

As mentioned above, our morphological analysis, as well as the initial molecular study, support recognition of Hylomus as a valid genus in agreement with Jeekel (1980a). We therefore consider Hylomus as a valid genus, separate from Desmoxytes . We further reallocate 33 species of Desmoxytes s.l. from China (19 species), Vietnam (ten species), Laos (three species) and Thailand (one species) to Hylomus (see Table 2).