Arrup dentatus (Takakuwa, 1934)

Published, First, 2007, The Mecistocephalidae of the Japanese and Taiwanese islands (Chilopoda: Geophilomorpha), Zootaxa 1396, pp. 1-84 : 13-15

Arrup dentatus (Takakuwa, 1934)

Figs. 10–13

[1] Prolamnonyx dentatus Takakuwa 1934a — Annot. Zool. Japon. 14: 359; fig. 7–8 (original description) Prolamnonyx dentatus: Takakuwa 1934b — Bot. & Zool. Tokyo 2: 707 (key) Prolamnonyx dentatus: Takakuwa 1934c — Bot. & Zool. Tokyo 2: 883; fig. 27–33 Prolamnonyx dentatus: Takakuwa 1938a — Annot. Zool. Japon. 17: 355 Prolamnonyx dentatus: Takakuwa 1938b — Bot. & Zool. Tokyo 6: 2030 (key)

[2] Prolamnonyx dentatus: Takakuwa 1940 — Fauna Nippon. 9: 94 (key); fig. 98–100 Prolamnonyx dentatus: Takakuwa 1943 — Bull. Biogeogr. Soc. Japan 13: 165 Prolamnonyx dentatus: Attems 1947 — Ann. Naturhistor. Mus. Wien 55: 105 (key) Prolamnonyx dentatus: Takashima 1949 — Acta Arachn. 11: 13 Prolamnonyx dentatus: Takashima & Shinohara 1952 — Acta Arachn. 13: 9 (key) Arrup dentatus: Crabill 1964 — Proc. Biol. Soc. Washington 77: 166

[ 3] Prolamnonyx dentatus: Shinohara 1972 — Mem. Nat. Sc. Mus. Tokyo 5: 66

[4] Prolamnonyx dentatus: Titova 1975 — Zool. Zh. 54: 47 (redescription, key); fig. 4b Prolamnonyx dentatus: Murakami 1993 — List Species Anim. Japan 5: 105 Prolamnonyx dentatus: Shinohara 1999 — Pictorial Keys Soil Anim. Japan: 709 Arrup dentatus: Bonato et al. 2003 — Syst. Entom. 28: 550, 551 Arrup dentatus: Foddai et al. 2003 — J. Nat. Hist. 37: 1261

Diagnosis. An Arrup species with body length reaching about 2 cm. Frontal line curved. Distal article of the telopodite of the second maxillae with a claw. Forcipular article III with a well developed tooth. Poison calyx only reaching the distal part of forcipular article I both in males and in females. Telopodites of the last leg­

bearing segments swollen in males, slender in females. Sternum of the last leg­bearing segment wider than long.

Type material. Holotype: male, 20 mm long, subadult ( Takakuwa, 1934a).

Type locality. ‘ Zyôzankei (bei Sapporo)’, Hokkaido ( Takakuwa, 1934a) .

Depository of type material. The holotype is probably lost (see Discussion).

Material examined. 3 specimens: 1 male, adult (17 mm), and 2 females, subadult (19 and 21 mm), from Mt. Soranuma­dake, Sapporo­shi , Hokkaido, 21.V.1985, M. Ohara leg., coll. AM and TT .

Description. Body length of adults reaching at least about 2 cm. Body colour yellow, without dark patches. Head 1.2–1.3 times as long as wide; frontal line curved. Antennae 2.1–2.5 times longer than the head width; apical sensilla about 10 m long. Clypeal setae: a median pair anterior to the plagulae and a group on each side of the clypeus, reaching the anterior corners. Clypeal ratio between about 2.0 and 2.5. Labrum: anterior ala triangular, medial margin reduced to a vertex; internal margins of side­pieces parallel, not touching each other; posterior margin of each side­piece sinuous, slightly convex close to the internal and external ends. First maxillae: anterior corners of coxosternum not projecting; each medial projection only slightly longer than wide, the internal margin with very short spines, the distal lobe about as long as wide; each telopodite about 2.5 times as long as wide, the distal lobe attenuated; hyaline scales on the dorsal sides of medial projections. Second maxillae: article I of the telopodite about 2.0 times as long as wide; article III about 2.5 times as long as wide, with a few setae only; apical claw present, quite stout. Forcipular segment: width to length ratio of exposed part of coxosternum about 1.1–1.3; cerrus absent; each pleuron with a distinct dorsal ridge, scapular point not reaching the anterior margin of coxosternum. Forcipules: article I about 1.5 times as long as wide, distal tooth well developed; article II almost without teeth; article III with a well developed tooth; tarsungulum with one basal, obtuse tooth; poison calyx only reaching the distal part of article I, in both sexes. Last leg­bearing segment: sternum sub­triangular, about 1.5–1.7 times as wide as long; telopodites more swollen in males than in females, with dense short setae on the ventral side, as dense in male as in female; one short apical spine.

Distribution in the considered area.

Hokkaido: ‘Zyôzankei’ [1] [currently Jyozankei] (type locality); Wakkanai, Engaru­cho (Monbetsu­gun), Konbu (Niseko, Niseko­cho, Abuta­gun) [2] (transcribed from Japanese); ‘ Poroshiri­sansô at the foot of Mt. Poroshiri­dake’ [3]; Mt. Soranuma­dake (new) .

General distribution. The species is known from Hokkaido, the Sikhote­Alin mountains [4] and the Kuril Islands .

[4]

Remarks. Arrup dentatus was described as new in two different papers published by the same author in the same year ( Takakuwa, 1934a, 1934c). Because we were not able to assess the actual date of publication of these papers, we provisionally consider the description by Takakuwa (1934a) as the original one, following the opinion of other authors ( Crabill, 1964; Shinohara, 1972).