Four new species of Amynthas earthworms (Oligochaeta: Megascolecidae) from the Central Mountain Range of southern Taiwan

Four new species of terrestrial earthworms belonging to the genus Amynthas (Megascolecidae: Oligochaeta) are described from the Central Mountain Range in southern Taiwan. Two octothecate species, Amynthas pavimentus sp. nov. and Amynthas biorbis sp. nov., were found at elevations of 2000-2700 m and 4121000 m, respectively, on both east and west slopes. Amynthas pavimentus has patched genital papillae between setal line and intersegmental furrow in VIII-IX and XVII-XX. Amynthas biorbis has a pair of large papillae adjacent to male porophores in XVIII. The other two species are the octothecate Amynthas libratus sp. nov., found at 1000 m, and the sexthecate Amynthas hongyehensis sp. nov., found at 950-1000 m, on the eastern slope. Amynthas libratus is related to A. pavimentus but has horizontal rows of papillae along setal lines or intersegmental furrows in VII-IX and XVII-XX. Amynthas hongyehensis has two pairs of large, presetal papillae medial to male porophores in XVIII and XIX.