Orphnus (Orphnus) brevialatus Frolov & Akhmetova, 2020

Frolov, Andrey V. & Akhmetova, Lilia A., 2020, Description of a new brachypterous scarab species, Orphnus brevialatus (Coleoptera: Scarabaeidae: Orphninae) from East Africa, with notes on flightlessness in the orphnines, Zootaxa 4750 (3), pp. 425-431 : 426

Orphnus (Orphnus) brevialatus Frolov & Akhmetova , new species

( Figs. 1 A–D, 2A–D)

Type material. Holotype, male with the label “ TANZANIA 16.XII.2006 Chunya to Mbeya, 2500 m Werner leg.” ( ZIN) . Paratype, female with the same data as the holotype ( ZIN) .

Description. Holotype, male ( Figs. 1 A–C, 2A–C). Body elongate, convex, shiny; length 11.8 mm, maximum width 5.8 mm. Color uniformly dark brown.

Head: Clypeus wide, with convex anterior margin, rounded laterally, finely crenulate. Genae small, not protruding past eyes. Frontal suture indistinct. Clypeus with long, slender horn, slightly curved posteriad ( Figs. 1B, C ). Dorsal surface of head almost impunctate. Labrum deeply sinuate in the middle, distinctly protruding past clypeus.

Pronotum: with rounded sides, about 1.2 times wider than long, with deeply concave disc and large lateral ridges almost triangular in lateral view ( Fig 1C ). Anterior angles acute; posterior angles rounded, indistinct in dorsal view. Pronotum bordered on anterior margin and base. Base of pronotum rugose. Sides with coarse, rounded punctures separated by about 0.5–1.0 puncture diameters. Lateral margins with long, sparse, brown setae.

Scutellum : wide, semicircular, about 1/16 the length of elytra.

Elytra: convex, about as wide as long, widest in the middle, with almost indistinct humeral umbones. Striae indistinct. Elytra with coarse, ocellate punctation; punctures denser near base and sparser on disc and in apical part.

Wings: reduced, about 1/3 length of elytra.

Legs: Protibiae with 3 outer teeth. Lateral margin basad of outer teeth not crenulate. Apical spur of protibia absent. Protarsi of the holotype broken. Middle legs and hind legs similar in shape; metafemora and metatibiae about 1/8 longer than the mesofemora and mesotibiae. Meso- and metatibiae somewhat triangular with 2 apical spurs, inner margin almost straight, with 1 transverse keel. Upper spur of tibiae as long as two basal tarsomeres. Claws 1/3 length of apical tarsomere. Femora almost impunctate.

Abdomen: Abdominal sternites irregularly punctate, pubescent, with sparse, long setae. Visible sternite 6 medially about 2 times longer than sternites 2–5 combined.

Pygidium: Surface irregularly punctate with transverse punctures.

Aedeagus: with relatively long (0.6 length of phallobase), curved downwards parameres tapering apically ( Fig. 2B ). Parameres spear-shaped in dorsal view, with angulate lateral teeth. Endophallus with 2 groups of microspinules and a cluster of larger spinules ( Fig. 2C ).

Female ( Fig. 1D ) differs from the male in having a relatively smaller pronotum without armature, frontoclypeus without process, presence of prothoracic spur. Body length of the female paratype 10.5 mm.

Diagnosis. From the other flightless Orphnus species, O. brevialatus new species differs in having a welldeveloped pronotal armature with two long, acute lateral processes. In the shape of the head, pronotum, and male genitalia it is similar to O. compactilis Quedenfeldt, 1884 but differs from it, in addition to the reduced wings and shorter body, in the shape of the endophallic armature.

Distribution. The new species is known from a single locality in Kipengere Range (Livingstone Mountains), the eastern escarpment of the East African Rift in East Africa. The label does not contain exact locality but suggests that the specimens were collected on the road between towns of Chunya and Mbeya ( Fig. 2D ).

Etymology. From Latin adjectives in the nominative singular brevis (= short), and alatus (= winged), referring to the reduced wings.

Figures

FIGURES 1A–D. Orphnus brevialatus Frolov & Akhmetova, new species, habitus. A–C, holotype, male (abdomen dissected); B, paratype, female.

FIGURES 2A–D. Orphnus brevialatus Frolov & Akhmetova, new species. A–C, holotype, male. A, aedeagus in lateral view; B, parameres in dorsal view; C, endophallus; D, locality map (red circle—O. brevialatus new species, black circle—O. longicornis Frolov et Akhmetova, white circle—O. valeriae Frolov et Akhmetova; terrestrial ecoregions: 1—tropical and subtropical moist broadleaf forests, 2—tropical and subtropical grasslands, savannas, and shrublands, 3—flooded grasslands and savannas, 4—montane grasslands and shrublands, 5—mangroves, 6—lakes).