Anchonidium perpensum Faust, 1886

Hlaváč, Peter, 2020, Review of the tribe Typoderini (Coleoptera: Curculionidae) from Caucasus with the description of a new species of Caulomorphus from Armenia, Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 60 (2), pp. 629-638 : 633-634

Anchonidium perpensum Faust, 1886 ( Figs 1d , 4e–f )

Anchonidium perpensum Faust, 1886b: 32 (original description).

Type locality. ‘Muchet’ [probably Mccheta, Georgia].

Type material. Hඈඅඈඍඒඉൾ: ♀, ‘ Muchet, Balassog [h] / Type [p, red label] / Coll.J. Faust, Ankauf 1900 [p] / Staatl. Museum für Tierkunde, Dresden [p] / HOLOTYPE Anchonidium perpensum Faust, P. Hlaváč det., 2016 [p, red label]’ ( SMTD).

Redescription. Body convex ( Fig. 1d ), dark reddish-brown, legs and antennae of same colour. Length 3.78 mm, maximum width of elytra 1.46 mm. Eyes oval, clearly visible dorsally. Rostrum curved downwards, with three longitudinal carinae, median carina wide, lateral carinae narrow. Antennal scrobe deep, straight, reaching lower border before eyes. Antennae with scape about 1.25× as long as funicule; antennomeres II and III elongate and expanded towards apex, II about 1.4× as long as III, antennomeres IV–VI subequal, quadrate, shortest, antennomere VII 1.25× as long as VI and 0.85× as long as VIII, antennal club about 2.33× as long as antennomere II and about 1.90× as long as wide. Pronotum about 1.07× as long as wide, 1.46× as long as head, widest in middle, basal margin slightly convex, with closely arranged large punctures which become smaller, even evanescent in anterior third. Elytra long, subparallel-sided, 1.35× as long as wide, 1.81× as long as pronotum, with 9 striae of large punctures, distance between punctures less than diameter of puncture, elytral interstriae flat, with macrosetae in posterior part, humeri prominent. Female terminalia. Spermatheca ( Fig. 4e ), female sternite VIII ( Fig. 4f ), plate large, with evenly rounded apex bearing short setae.

Remarks. The original description of A. perpensum is based on a unique female specimen (thus holotype by monotypy) from Muchet in Caucasus (Fൺඎඌඍ 1886b), which is most likely referring to Mccheta, ancient capital of Georgia situated close to Tbilisi. Despite many specimens of Anchonidium collected around Tbilisi, this species has never been recorded again since its original description. The study of the holotype revealed that this species is distinct from the widely distributed A. caucasicum . However, study of more specimens and particularly male would be desirable to confirm this hypothesis.

Differential diagnosis. Two Caucasian species can be separated using the key bellow.

Distribution. Georgia, so far known only from the type locality the exact location of which is not known for certain.

Key to the species of Anchonidium

from the Caucasus Region

1. Head longer, PL/HL ratio = 1.35–1.40; rostrum with dense setae; anterior median part of pronotum as densely punctate as on posterior two thirds; elytra evenly rounded; spermatheca with short corpus and cornu, corpus at apex with shallow excavation ( Fig. 4c ). ....................... A. caucasicum ( Motschulsky, 1845)

– Head shorter, PL/HL ratio = 1.46; rostrum with sparse setae; anterior median third of pronotum with smaller punctures than on posterior two thirds; surface close to anterior margin with very sparse punctation; elytra in anterior two thirds more parallel-sided; spermatheca with longer and slenderer corpus and cornu, corpus at apex rounded ( Fig. 4e ). ...... A. perpensum Faust, 1886

Figures

Fig. 1. Dorsal habitus. a – Adexius scrobipennis Gyllenhal, 1834; b – Anchonidium caucasicum Motschulsky, 1845; c – Caulomorphus kociani sp. nov.; d – Anchonidium perpensum Faust, 1886; e – Aparopion costatum (Fåhraeus, 1843); f – Pseudaparopion kadleci Borovec, Osella & Zuppa, 2002.

Fig. 4. Anchonidium caucasicum Motschulsky, 1845: a – antenna; b – abdominal ventrites I–V; c – spermatheca; d – sternite VIII. Anchonidium perpensum Faust, 1886: e – spermatheca; f – sternite VIII. Aparopion costatum (Fåhraeus, 1843): g – antenna. Scale bars: 0.2 mm.