Mecistocephalus ongi Takakuwa, 1934

Published, First, 2007, The Mecistocephalidae of the Japanese and Taiwanese islands (Chilopoda: Geophilomorpha), Zootaxa 1396, pp. 1-84 : 44-45

Mecistocephalus ongi Takakuwa, 1934

Fig. 53

[1] Mecistocephalus ongi Takakuwa 1934d — Trans. Nat. Hist. Soc. Formosa 24: 221 (original description); fig. 1 Mecistocephalus ongi: Takakuwa 1934a — Annot. Zool. Japon. 14: 360; fig. 9–10 Mecistocephalus ongi: Takakuwa 1934c — Bot. & Zool. Tokyo 2: 884

[2] Mecistocephalus (Mecistocephalus) ongi: Takakuwa 1936b — Trans. Nat. Hist. Soc. Formosa 26: 434 (key) Mecistocephalus (Mecistocephalus) ongi: Takakuwa 1938a — Annot. Zool. Japon. 17: 354 Mecistocephalus ongi: Verhoeff 1939 — Zool. Jahrb. Syst. 72: 86

[3] Mecistocephalus (Mecistocephalus) ongi: Takakuwa 1940 — Fauna Nippon. 9: 69 (key); fig. 65 Mecistocephalus ongi: Gressitt 1941 — Ann. Mag. nat. Hist. 8: 56 Mecistocephalus ongi: Takakuwa 1942b — Micron. Sci. 5: 17

[4] Mecistocephalus ongi: Takakuwa 1942c — Trans. Nat. Hist. Soc. Formosa 32: 359 Mecistocephalus ongi: Takakuwa 1943 — Bull. Biogeogr. Soc. Japan 13: 170 Mecistocephalus ongi: Attems 1947 — Ann. Naturhistor. Mus. Wien 55: 101 (key) Mecistocephalus ongi: Murakami 1993 — List Species Anim. Japan 5: 105 Mecistocephalus ongi: Wang & Mauriès 1996 — Mém. Mus. natn. Hist. Nat. Paris 169: 89 Mecistocephalus ongi: Shinohara 1999 — Pictorial Keys Soil Anim. Japan: 709

Diagnosis. A Mecistocephalus species with 49 leg­bearing segments. Body length reaching at least 3 cm in adults. Trunk without dark patches. Head 1.7 times as long as wide. Areolate part of the clypeus without smooth insulae, each side with about 10 setae; clypeal ratio about 2–3. Buccae with setae in the posterior half only. Sternal sulcus furcate. Sternum of the last leg­bearing segment as wide as long.

Type material. Syntypes: number, sex and age not stated, length up to 30 mm ( Takakuwa, 1934d), at least one adult male (age inferred from original drawings).

Type locality. ‘ Tainan (Formosa)’, Taiwan ( Takakuwa, 1934d) .

Depository of type material. The syntypes are probably lost (see Discussion).

Material examined. None.

Description. Body size reaching at least 3 cm in adults. Body colour yellow, without dark patches; head and forcipular segment darker. Head 1.7 times as long as wide. Clypeus: clypeal ratio 2–3; areolate part without smooth insulae; about 10 setae on each side of the clypeus; plagulae without evident sensilla or setae. Labrum: anterior ala subtriangular, posterior margin of each side­piece sinuous, slightly convex close to the internal and external ends. Spiculum present, buccae with setae on the posterior half only. Mandible: about 5 well­developed lamellae; first lamella with about 7 teeth; average intermediate lamella with about 10 teeth. Forcipules: article I with two teeth, similar in size; articles II and III each with a small tooth. A total of 49 legbearing segments. Sternal sulcus furcate, with a right angle between the branches. Last leg­bearing segment: sternum subtriangular, about as wide as long; about 13–14 coxal pores on each coxopleuron.

Distribution in the considered area.

Ogasawara Islands: ‘Chichi­jima, Ogasawara­shoto’ [3].

Taiwan: ‘Tainan’ [1]; ‘Kakeirin, Taiwan, Kagi, Miyosi’ [2], Jiayi, Jiayi­xian; Huaxi, Hualianxi­xian; Sanhao; Tainan, Tainan­xian; Dong­gang, Gaoxiong­xian or Yilan­xian; Xizhou, Zhanghua­xian; Xinying, Tainanxian; Houguilin [3] (transcribed from Japanese); Shilin (Shilin, Taibei, Taibei­xian) [4] (transcribed from Japanese) .

General distribution. Ogasawara Islands, Taiwan and Micronesia [3].

Remarks. Notwithstanding the lack of detailed information this species can be easily distinguished from all other mecistocephalid species occurring in the Japanese­Taiwanese area for the unusually high clypeal ratio (about 2 according to the original description and illustration, 2–3 according to Takakuwa 1936b), and the presence of about 10 setae on each side of the clypeus. M. brevisternalis appears very similar to M. ongi , the only known difference being in the sternum of the last leg­bearing segment, which is about as wide as long in M. ongi , but about 2 times as wide as long in M. brevisternalis . Worth notice is that both species were described by the same author in the same paper.