Cyphochilus obscurus Sharp 1876
Creators: name: Sabatinelli, Guido
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Melolonthidae
Cyphochilus
Cyphochilus obscurus

description: Cyphochilus obscurus Sharp, 1876
Figs 4, 50-52, 87
Cyphochilus obscurus Sharp, 1876: 83.
Type material examined: Holotype: MNHN: 1 ♂; LAOS: // Cyphochilus obscurus / Laos. Type / D. S. (H) // Laos (H) / Mouhot (P) // Ex Musaeo / D. Sharp 1890 (P) // Muséum Paris / 1952 / Coll. R. Oberthur (P) // Typus (H on red) //. (Figs 4, 87).
Additional material examined: 8 specimens.
LAOS: ISNB; 1 ♂; Paklay; 15.VIII.1917; R. Vitalis de Salv [aza] – ISNB; 1 ♂; Luang Prabang; 27.VIII.1917; R. Vitalis de Salv [aza]. – ISNB; 2 ♂; Laos, Pak. [?]; 24.IX.1919; coll. R. Vitalis de Salv [aza].
THAILAND: PCMN; 2 ♂; Chiang Mai; X.1989. – MHNG; 3 ♂; Nan; VIII.1993. – MHNG; 3 ♂; Wiang Papao, 80 km NE Chiang Mai, 1992.
Redescription of the holotype male: Size – BL: 16.4 mm, BW: 7 mm, BWX: 8.7 mm, situated at midpoint of elytra. Color – Integument light brown; surface with white scales densely aggregated on the sides of pronotum. Head – CW/L: 2.6; clypeus largely rounded; (F/O: 3.4); antennal club slightly longer than antennomeres 2-7 (A2-7/CL: 0.8). Pronotum – (PnW/L: 2); apical angles and lateral margins largely flattened, apical angles right, not protuberant; basal lateral margins straight, basal angles obtuse. Elytra – Without any visible striae. Thoracic sterna – Surface with short, white pubescence and scales; mesosternum feebly developed (MstL: 0.47 mm) however, visible in lateral view between the mesocoxae. Abdomen – Sternites only with scattered scales; pygidium convex with apical margin very narrowly reflected. Legs – Protibia tridentate with the basal tooth vestigial; slender apical tooth as long as the middle tooth; claws of all tarsi bifid at apex. Aedeagus – Parameres strongly asymmetric with 5 appendices 50-52; the right paramere in form of club with an apical spike directed externally (Fig. 51).
Variability: BL: 16-17.5 mm. Specimens from Thailand have the vestiture with ochre scales instead of white, however, this is a variation observed also in other species of Cyphochilus.
Female: Unknown.
Type locality: The type locality is given as Laos.
Distribution: The species is known from only a few specimens, all from North Laos and North Thailand.
Remarks: Sharp (1876) thought that the holotype of C. obscurus was a female, however it is a male. Cyphochilus obscurus can be readily separated from all other congeners by the unique form of the parameres. Moreover, the bifid claws are an astonishing character since all other Cyphochilus have claws with a thorn in medial position, never bifid. Actually, this is a quite strong character utilized to separate group of genera in the Rhizotrogini, however, all other characters attribute this species to genus Cyphochilus without any doubt.
description: Published as part of Sabatinelli, Guido, 2020, Taxonomic notes on the genus Cyphochilus Waterhouse, 1867 (Coleoptera, Scarabaeoidea, Melolonthinae) with description of 10 new species, pp. 157-181 in Revue suisse de Zoologie 127 (1) on page 172, DOI: 10.35929/RSZ.0014, http://zenodo.org/record/5743429