Epistomius janaki, Borovec & Skuhrovec, 2017

Borovec, Roman & Skuhrovec, Jiří, 2017, Epistomius, a new genus of African forest litter Trachyphloeini, with descriptions of seven new species (Coleoptera: Curculionidae: Entiminae), Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 57 (2), pp. 645-676 : 661-663

Epistomius janaki sp. nov.

( Figs 3C , 7A–G )

Type locality. South Africa, KwaZulu Natal, Howick, Karkloof Range, 29°19.1′S, 30°15.5′E, 1325 m a.s.l.

Type material. HOLOTYPE: ♂, ‘ South Africa, KwaZulu Natal , Howick, Karkloof Range, 29°19.1′ S 30°15.5′ E, 23.xi.2006, 1325 m, J. Janák lgt.’ ( TMSA) . PARATYPES: 16 ♂ ♀, the same data as holotype ( JJRC, JSPC, NMPC, RBSC) ; 7 ♂ ♀, ‘ South Africa, KwaZulu Natal, Karkloof NR, 29°18.5′ S 30°13.2′ E, 2.i.2015, indig. forest, J. Janák lgt.’ ( JJRC, RBSC) ; 23 ♂ ♀, ‘RSA (E) [ South Africa, East], KwaZulu-Natal, Doreen Clark Nat. Res. nr. Pietermaritzburg , 29.5787 S / 30.2892 E, 7.11.2013, 1110 m, sifted litter, leg. M. Wanat’ ( MNHW) ; 17 ♂ ♀, ‘ South Africa, KwaZulu-Natal, Fort Nottingham Nat. Reserve , 29°24.6′ S 29°54.8′ E, 22.i.2016, ind. forest, Berlese extraction, leaf & log litter, sifting, J. Janák lgt.’ ( JJRC, RBSC) ; 1 ♂, ‘ South Africa, KwaZulu Natal, PMB env.- Sweetwaters NR, 29°35.65′ S 30°18.0′ E, 3.i.2015, indig. forest, J. Janák lgt.’ ( RBSC) ; 2 ♂ ♀, ‘ South Africa, KwaZulu Natal, Nkandla Forest Reserve , 28°43.8′ S 31°8.3-8.4′ E, 4.i.2015, indig. forest, J. Janák lgt.’ ( RBSC) .

Description ( Figs 7A–G ). Body length 1.63–2.06 mm, holotype 1.65 mm. Body dark brownish, basal half of scape or complete scape, funicle, club, short apical part of tibiae and tarsi reddish brown, tarsi sometimes paler. Elytra with moderately sparse appressed scales, 3–4 across width of one interval, irregularly subcircular, finely longitudinally striate. Pronotum and head with rostrum with dense subcircular scales, with fine fan-shaped striae, creating short, fine and dense fringes on almost half of circumference, almost covering integument. Appressed scales on scape, femora and tibiae similar to pronotal ones, slightly smaller. Elytra with subspatulate setae, apically rounded, finely longitudinally striate, creating one regular row on each interval, distance between two setae on posterior part slightly longer than length of one seta, very different on anterior third and posterior declivity. Anterior third with setae semiappressed, inconspicuous, about as long as half width of interval, posterior declivity with setae erect, about as long as width of one interval. Pronotum and head with rostrum with semiappressed subspatulate setae similar to those on anterior part of elytra, irregularly scattered, setae on interocular space twice as long as the others. Scape, femora and tibiae with short, long-oval semiappressed setae, densely irregularly scattered, hardly visible, not prominent from outline. Body vestiture light brownish, raised setae paler, greyish brown.

Head ( Figs 7A–D ). Rostrum in both sexes ( Figs 7B–C ) in basal third tapered apicad, in apical two thirds regularly enlarged apicad, in males more than in females, in males ( Fig. 7B ) 1.10–1.16× as wide as long, at apex 1.04–1.05× as wide as at base; in females ( Fig. 7C ) 1.18–1.22× as wide as long, at base as wide as at apex, in both sexes at apex distinctly narrower than head including eyes. Epifrons with slender longitudinal median stria, when cleared of scales shiny with two very slender keels, distinctly enlarged apicad from fovea at interocular space and creating triangular, shallowly deepened space with several fine punctures and short striae and with very slender and fine longitudinal median stria. Frons deepened, shortly densely and finely longitudinally striate. Epistome in males wider than epifrons at midlength, in females narrower, about equally wide as epifrons at midlength. Head when cleared of scales convex with fine longitudinal striae, radiate from fovea posteriad. Eyes weakly prominent from outline of head.

Antennae ( Fig. 7A ). Antennal scape 4.9–5.0× as long as wide and 1.5–1.6× as long as funicle, at apex equally wide as club. Funicle segment I 1.7–1.8× as long as wide and 1.7–1.8× as long as segment II, which is 1.3–1.4× as long as wide; segments III–V 1.3–1.4× as wide as long; segment VI 1.4–1.5× as wide as long; segment VII 1.3–1.4× as wide as long. Club 1.9–2.0× as long as wide.

Pronotum ( Fig. 7A ) in males 1.50–1.53×, in females 1.56–1.64× as wide as long, widest just behind midlength, with distinctly rounded sides. When cleared of scales regularly convex, shiny, sparsely irregularly coarsely punctured, punctures shallow with small ring inside, distance between two punctures shorter than diameter of one puncture, anterior border dark brownish, bordered by transverse dense row of fine punctures. Pronotum in lateral view slightly convex, behind anterior border lowered.

Elytra ( Fig. 7A ) in males 1.12–1.14×, in females 1.20–1.28× as long as wide.

Legs ( Figs 7A, E ). Tarsomere II 1.5–1.6× as wide as long; tarsomere III 1.3× as wide as long and 1.2–1.3× as wide as tarsomere II; onychium 1.5× as long as tarsomere III.

Male genitalia ( Figs 3C , 7G ). Penis longer than wide, slender, widest in apical third, apically broadly rounded with separated small tip.

Etymology. The new species is dedicated to a long-time friend of the first author, Jiří Janák (Rtyně nad Bílinou, Czech Republic), an eminent specialist in Staphylinidae of the Palaearctic and Afrotropical Regions and collector of part of the type material, who directed the first author to specialise in weevils, when both had just started their interest in entomology.

Biology. The type material was sifted from native forest litter.

Distribution. South Africa: KwaZulu-Natal ( Fig. 4 ).

Differential diagnosis. The species is characterized by elytral setae on apical declivity semierect to erect, rostrum in males enlarged apicad, with epistome wider than epifrons, and it is thus similar to E. colonnellii sp. nov., from which it can be distinguished by the following characters: elytral setae on posterior declivity subspatulate, rounded apicad, 4–5× as long as inconspicuous setae on basal half; tarsomere II 1.5–1.6× as wide as long; elytra in males shorter, 1.12–1.14× as long as wide; and penis distinctly longer than wide, with separated tip at apex and concave before it.

Figures

Fig. 3. Apex of penis.A – Epistomius bulirschi sp. nov.; B – Epistomius colonnellii sp. nov.; C – Epistomius janaki sp. nov.; D – Epistomius natalensis sp. nov.; E – Epistomius ngomiensis sp. nov.; F – Epistomius niger sp. nov.; G – Epistomius wanati sp. nov.

Fig. 7. Epistomius janaki sp. nov. A – habitus, dorsal view, holotype, male; B – rostrum, male, dorsal view; C – rostrum, female, dorsal view; D – rostrum, male, lateral view; E – protibia, male; F – spermatheca; G – aedeagus. Scale bars: 1 mm (A), 0.5 mm (G) and 0.2 mm (F).

Fig. 4. Distribution of Epistomius species in South Africa; Epistomius bulirschi sp. nov. (yellow circle); Epistomius colonnellii sp. nov. (brown circles); Epistomius janaki sp. nov. (violet circles); Epistomius natalensis sp. nov. (blue circles); Epistomius ngomiensis sp. nov. (red circles); Epistomius niger sp. nov. (green circles); and Epistomius wanati sp. nov. (orange circle).