Caccothryptus arakawae, Matsumoto, 2021

Matsumoto, Keita, 2021, Six new species of the genus Caccothryptus from the Himalayas (Coleoptera: Limnichidae), European Journal of Taxonomy 739, pp. 168-184 : 171-173

Caccothryptus arakawae sp. nov.

urn:lsid:zoobank.org:act:FB863BA1-2C04-435A-869C-5C6A16C82964

Figs 2 , 7B

Diagnosis

Caccothryptus arakawae sp. nov. is within the C. testudo group and can be distinguished by several genital characters: (1) apex of median lobe narrows with tip slightly pointed in ventral view; (2) concave structure between apical emargination narrow U-shaped with rounded end; (3) dorsal side of parameres bisinuate in lateral view; (4) apical emargination of parameres V-shaped in ventral view.

Etymology

This species is named after Hiromi Arakawa, who is a Japanese manga artist.

Material examined

Holotype NEPAL • ♂; “NEPAL: 5600’ Kathmandu Dist. , Godawari, 24.v.-6.vi.1983. // M.J.D.Brendell BMNH(E) 1983-222 // At light // NHMUK011225268 ”; BMNH.

Paratypes NEPAL • 3 ♂♂; same collection data as for holotype with additional label; “ NHMUK011225269 ”, “ NHMUK011225270 ”, “ NHMUK011225271 ”; BMNH • 2 ♀♀; same collection data as for holotype with additional label; “ NHMUK011225272 ”, “ NHMUK011225273 ”; BMNH .

Description

Male

BODY. Elongate, oval, dorsum convex, EL: 3.39 mm, EW: 2.36 mm, PL: 0.93 mm, PW: 2.03 mm. Colour: dorsal side brown; venter brown, tibia reddish brown, tarsal claws light brown. Dorsal surface densely covered with long setae with patches of white setae forming a wavy pattern, ventral surface with relatively long setae.

DORSUM. Head: partially retracted into pronotum; overall surface smooth, densely punctured across surface. Antennae: 11 segmented, filiform, fully pubescent, antennomeres long and slender, 1 st AS widest, 2 nd AS narrow and long, 3 rd AS smallest, 4 th –11 th AS long, thin and obtusely angled on one side. Pronotum: transverse, widest at posterior end, narrowest at anterior end, narrower than elytra; anterior margin convex, posterior margin trisinuate, lateral margin convex; surface covered with dense punctation, surface between punctures smooth and shiny. Scutellum: subtriangular, large, lateral sides nearly straight. Elytra: Longer than wide; anterior margin slightly convex, sinuate; anterior lateral angle nearly right angled, rounded; lateral margins strongly bordered; surface with mixtures of small fine and medium sized punctuations; surface between punctures smooth and shiny.

VENTER. Prosternum: concave on anterior margin, outer lateral margin concave; prosternal process as long as wide, lateral margin sinuated, posterior margin rounded. Mesoventrite: wider than long, narrowed towards posterior; anterior end concave where prosternal process fits, discrimen visible; laterally subparallel and gently curved, posteriorly flat, anteriorly trisinuate. Metaventrite: long and wide, flat on middle; discrimen not clearly visible. Abdomen: five clearly visible ventrites. Intercoxal process with pointed apex. Posterior margin of 1 st and 2 nd ventrites convex, 3 rd –4 th ventrites slightly concave around middle, 5 th ventrite curved. Surface covered with long, light yellow, recumbent setae.

LEGS. Tibia: protibia with outer and inner lateral ends curved. Meso- and metatibia with outer lateral margin almost straight, inner lateral margin straight. Tarsi: simple, segments increase in length towards apex, 5 th tarsal segment as long as 1 st –4 th tarsal segment combined. Tarsal claws: long, narrow, symmetrical.

GENITALIA. Aedeagus: elongate, strongly sclerotised. Base: asymmetrical, widest around basal 0.2 from lateral, relatively consistent width in ventral view. Median lobe: approximately 2 / 5 length of genitalia; longer than parameres; slightly bisinuate on dorsal side, bisinuate on ventral side, widest at near apical end, narrowing towards the apex, apex rounded in lateral view; apex flat split into two on anterior half and edge pointed, lower half of lateral end relatively straight in dorsal view; lower half narrows, upper half oval and tip slightly rounded in lateral view; apical end smooth and narrows inwards in ventral view. Parameres: wider than median lobe in ventral view; apical emargination V-shaped, concave structure between parameres elongated slightly narrow and deep U-shape with rounded end; bisinuate, lower half of sinuation long and shallow, upper half short and slightly deep on dorsal side in lateral view; gently curved on ventral side in lateral view; apex rounded and ever so slightly overlapping with median lobe, majority of parameres do not overlap median lobe with two spaces visible in lateral view.

Female

No morphological difference from male except for the longer 5 th abdominal ventrite. Ovipositor long, gonocoxites strongly tapering to a point.

Morphological variation

EL: 3.68‒ 3.39 mm, EW: 2.52‒ 2.35 mm, PL: 1.00‒ 0.90 mm, PW: 2.11‒ 2.03 mm.

Distribution

Caccothryptus arakawae sp. nov. is known only from the type locality.

Figures

Fig. 2. Caccothryptus arakawae sp. nov., ♂, holotype (NHMUK011225268). A. Dorsal habitus. B. Genitalia, dorsal. C. Genitalia, lateral. D. Genitalia, ventral.

Fig. 7. Close-up of Caccothryptus spp. genitalia ventral apex, ♂, holotype. A. C. brendelli sp. nov. (NHMUK011225276). B. C. arakawae sp. nov. (NHMUK011225268). C. C. championi sp. nov. (NHMUK011225382). D. C. larryi sp. nov. (NHMUK011225324). E. C. tardarsauceae sp. nov. (NHMUK011225274). F. C. abboti sp. nov. (NHMUK011225275).