Ochthebius (Asiobates) erinaceus, Bilton, 2023

Bilton, David T., 2023, New species and new records of minute moss beetles from East Africa (Coleoptera: Hydraenidae), Acta Entomologica Musei Nationalis Pragae 63 (1), pp. 103-110 : 108-109

Ochthebius (Asiobates) erinaceus sp. nov.

( Figs 1–2 , 4 )

Type locality. Malawi, Mt. Mulanje, ca. 0.7 km ENE of Chambe Hut on Chambe Plateau, 15°54′18.7″S 35°32′50.4″E, 1953 m.

Type material. HOLOTYPE: J, labelled:“ MALAWI:Mt. Mulanje / Chambe plateau, Chambe hut / 1953m, sifting / S15°54’18.7’’ E35°32’50.4’’ / 21.XI.2018 P.Hlaváč lgt.” ( NMPC) with red holotype label . PARATYPE: 1 ♀ same data as Holotype and with red paratype label ( NMPC).

Description. Male. Colour. Dorsum ( Fig. 1C ) with head dark brown to black, ocelli paler, setae creating a weakly aeneous appearance at anterior margins of frons and on clypeal ridges; pronotum dark brown on disc, paler reddish brown on lateral areas; elytra dark reddish brown; venter rufopiceous, underside of head, metaventrite and apex of abdomen rufous; maxillary palpi, antennae and legs dark yellow-brown; antennal club darker than stem.

Head. Eyes rather small, in dorsal aspect 10 weakly convex facets in longest series. Frons shining, with dense, coarse punctures bearing short, golden suberect setae; interocular foveae large, round, deep, width of each about 1/3 width of head between compound eyes, each internally with few setiferous punctures. Clypeus smooth and shining, with medium punctures bearing short, stout, recumbent, golden setae. Labrum shining, very sparsely setiferously punctate; anterior margin with distinct, shallow apicomedian emargination.

Pronotum transverse, widest at middle.Anterior margin sinuated around middle, with narrow hyaline border and small, sharp, postocular emarginations. Sides arcuate; strongly excised in posterior 1/4, excised portion separated from anterior 3/4 by strongly acuminate acute projection; with narrow hyaline border restricted to excised portion. Posterior margin broadly arcuate around centre, with narrow hyaline border, most visible over central 1/2. Disc shining, with very coarse, dense, often confluent punctation; punctures reticulate and bearing short, stout, golden, recumbent setae. Median longitudinal sulcus distinct, deepened anteriorly and posteriorly; floor punctate. Admedian foveae distinct, elongate, anterior shorter than posterior. Adlateral foveae distinct, anterior elongate, posterior transverse, confluent with posterior admedian fovea.

Elytra stout and arched, widest at middle; shoulders sharply acuminate. Sides arcuate, with broad explanate margin.Apices narrowly separately rounded, slightly acuminate. Ten-seriate punctate, series not striate-impressed but intervals slightly tumid, particularly on disc. Serial punctures large, slightly transverse, each bearing a short, stout, erect, somewhat spathulate seta, arising from just behind anterior margin of puncture. Surface between punctures weakly shining, without visible microreticulation.

Venter. Mentum shining, with long, curved, stout setae close to anterior margin and anterolateral angles; surface moderately sparsely punctate, each puncture bearing a stout, flattened, decumbent seta. Posterior margin of compound eyes abruptly incised, with dense field of short, erect, white setae occupying sides of head below posteroventral margin of eyes. Metaventrite pubescent laterally, shining on disc, glabrous, with sparse, coarse punctures, bearing stout semi-erect setae. Abdominal ventrites 1–5 with medium, fine, reticulate punctation, punctures bearing fine, recumbent setae, some of which reach past anterior margin of next ventrite. Ventrite 6 minutely reticulated, with sparse, irregular row of fine setae close to base. Last tergite slightly acuminated apically.

Legs. Underside of basal protarsomeres with stout suction setae.

Aedeagus ( Fig. 2C ). Main piece evenly curved in lateral view, with hooked apex to terminal piece.

Female. Externally similar to male, other than absence of suction setae on fore-tarsi and last tergite strongly acuminated, with broad, flattened, modified setae close to posterior margin.

Variation. Measurements. Holotype BL = 1.75 mm; EL = 1.10; EW = 0.85 mm. Paratype female BL = 1.80 mm; EL = 1.10; EW = 0.90 mm.

Differential diagnosis. Asiobates Thomson, 1859 is a largely Palaearctic subgenus ( JÄCH 1990), with approximately 20 species known from the Americas, mainly North ( PERKINS 1980). Only five named species are known currently from the Afrotropical Region, one of which ( O. andreinii Régimbart, 1905 ) has been divided into four subspecies ( ORCHYMONT 1948). Of these, O. andronius Orchymont, 1948 was raised to species level by PERKINS & BALFOUR- BROWNE (1994), and it is likely the other three also represent good species. The new species is immediately distinguished from all other described members of the subgenus by the spathulate (sub-) erect setae on the dorsum. Aedeagus characteristic ( Fig. 2C ).

Etymology. Named in reference to the stout setae on the dorsum, which mean that the species bears some resemblance to a hedgehog (e.g. the African Hedgehogs, Atelerix Pomel, 1848 ). The specific epithet, erinaceus , is an adjective.

Distribution and ecology. Known only from the type locality, a remnant patch of indigenous forest on the Chambe Plateau, a northwestern outlier of Mount Mulanje ( Fig. 4 ). Specimens were sifted from forest litter and the species is likely terrestrial.

Figures

Fig. 1. Malawi Hydraenidae, habitus. A – Coelometopon dedzae sp. nov.; B – Hydraena mulanje sp. nov.; C – Ochthebius erinaceus sp. nov.

Fig. 2. Malawi Hydraenidae, aedeagus, lateral and ventral views. A – Coelometopon dedzae sp. nov.; B – Hydraena mulanje sp. nov.; C – Ochthebius erinaceus sp. nov.

Fig. 4. Distribution map for taxa covered in this paper. Red circles indicate localities for Decarthrocerus jeanneli Orchymont, 1948 (bordered circle type locality).