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This paper describes a new species of gigantic terrestrial earthworm Metaphire taiwanensis sp. nov. from western Taiwan. It reached the maximum length of 860 mm for a living clitellate and 637 mm after preservation. It is an autochthonous species found in Mt Beidongyan and the Meifeng area of the Central Mountain Range at elevations of 1800-2100 m. M. taiwanensis is octothecate and protandric, characters shared by Metaphire stephensoni (Michaelsen) of Indochina, and Metaphire bununa Tsai, Tsai and Liaw and Metaphire paiwanna Tsai, Tsai and Liaw of Taiwan. These four species are combined as a new species-group called the stephensoni -group within the genus Metaphire Sims and Easton. It is closely related to the congeneric ignobilis species-group, which is also octothecate but holandric. It differs from holandric and quadrithecate Metaphire magna (Chen) of Hainan Island, in which the length also reaches 700 mm. Specific variation and evolutionary trends in sizes and segment numbers of the Pheretima genus-group are discussed. [ABSTRACT FROM AUTHOR]

This paper describes a new species of athecate earthworm belonging to the illotus species-group of the genus Amynthas Kinberg from Taiwan. It is Amynthas hohuanmontis sp. nov. from Mt Hohuan at an elevation of 3000 m in the Central Mountain Range. The athecate earthworm Amynthas pusillus (Ohfuchi) from Ishigaki Island, Riukiu is found to be synonymous with Amynthas assacceus (Chen) from Hainan Island, China. Accordingly, the A. illotus species-group currently consists of A. hohuanmontis sp. nov. from Taiwan, A. illotus (Gates) from Yunnan and Riukiu, A. assacceus (Chen) of Hainan and Riukiu, A. sheni (Chen) from Hong Kong and A. oyuensis (Ohfuchi) from Japan. Based on characters of particularly the porophore structure, the five species are divided into two species-subgroups: the sheni species-subgroup of A. sheni and A. hohuanmontis , and the assacceus species-subgroup of A. illotus, A. assacceus and A. oyuensis. The two subgroups might have differentiated from two independent ancestors. The five species show an arc-shaped distribution in the peripheral regions of the East Asian continent (Yunnan, Hainan, Hong Kong, Taiwan, Riukiu and Japan), suggesting them to be survivors from the Pleistocene ice ages. [ABSTRACT FROM AUTHOR]

Earthworm specimens collected in southern Taiwan consisted of seven new species of Amynthas and several previously known species, mostly widely distributed peregrines. The new species are A. nanrenensis of the octothecal A . corticis species group, A. monsoonus and A . huangi of the sexthecal A . aelianus species group, and four proandric octothecal species: A . chaishanensis , A . hengchunensis , A . kaopingensis and A . ailiaoensis . Amynthas chaishanensis has dorsal intrasegmental spermathecal pores, but the other three proandric species have dorsal, lateral or ventral intersegmental spermathecal pores, respectively. The proandric species are united by several features, including the enclosure of segment xi in a sac, as in A. formosae (also proandric), octothecal with spermathecae in vi-ix, spermathecal diverticula stalks generally kinked and often enclosed in membrane, and prostatic ducts divided polytomously into numerous small ductlets, which may be grouped into bundles of two to five. In A. ailiaoensis the prostatic duct trunk contains up to seven separate lumens in the ental half, surrounded by the circular muscle of the duct, while in A . chaishanensis the prostatic duct trunk contains about 40 small lumens. Of the previously known species in the collection, Pontodrilus litoralis and Metaphire houlleti are first reported from Taiwan. Additional locations for A . incongruus and A . robustus are given, and in the latter case the material appears to be the usual male-sterile morph. Other species found are Pontoscolex corethrurus , Amynthas corticis , A . gracilis , Metaphire californica , and Polypheretima elongata . [ABSTRACT FROM AUTHOR]