Elaeidobius piliventris Haran & Kuschel, 2020

Haran, Julien M., Beaudoin-Ollivier, Laurence, Benoit, Laure & Kuschel, Guillermo, 2020, Revision of the palm-pollinating weevil genus Elaeidobius Kuschel, 1952 (Curculionidae, Curculioninae, Derelomini) with descriptions of two new species, European Journal of Taxonomy 684, pp. 1-32 : 17-20

Elaeidobius piliventris Haran & Kuschel sp. nov.

urn:lsid:zoobank.org:act:0B74EAD6-28CE-4DC7-B12E-E8362448470C

Figs 1F , 3B , 4F , 5 J–K

Etymology

The name piliventris is a Latin adjectivised noun derived from ‘pilus’ for ‘hair’, and ‘venter’ for ‘belly’.

Material examined

Holotype

GHANA • “GHANA. Kumasi. 21.x.1977. R.A. Syed ” “ex ♂ inflorescence. oil palm” “ Elaeidobius sp. indet. A R.T. Thompson det. 2004” “ Holotype [red label] Elaeidobius . piliventris . Haran & Kuschel. Haran & Kuschel 2019”; NHMUK.

Paratypes

GHANA • 1 ♂, 1 ♀; “GHANA (Central Reg.). Egyirkom (site 8). CABI study sample” “ Elaeidobius sp. indet. A R.T. Thompson det. 2004” “Paratye. Elaeidobius . piliventris . Haran & Kuschel. Haran & Kuschel 2019”; NHMUK .

Other material

ANGOLA • 1 ♂; CE Salazar ; 9.16º S, 14.55º E; 14 May 1973; Carvalho leg.; oil palm inflorescence; TMP .

DEMOCRATIC REPUBLIC OF CONGO • 9 specs; Yambula ; 23 Jan. 2018; E. guineensis ; JHAR02182 ; CBGP .

CAMEROON • 1 ♂; Kienké ; 2009; JHAR293_0102 ; CBGP .

Description (♂ ♀)

BODY LENGTH. 2.3–3.0 mm.

COLOUR (Ƌ). Yellowish or reddish brown, pronotum usually with vague, dark stripe, elytra with a short dark stripe on interstria 6 in basal third, and an oblique stripe from near middle of interstriae 3 or 4 to 8; integument with very short, scattered recumbent white hairs, usually forming 1–2 series on each interstria of elytron; in male elytra lacking long erect setae on margins, suture and at base of interstria 4.

HEAD. Strongly punctate, punctuation party confluent towards frontal fovea; forehead flat between eyes; rostrum in male as long as or 1.1 × as long as prothorax, in female 1.2–1.4 × longer, cylindrical, 5-carinate in basal ¾, median carina widening near antennal insertion, apical ¼ smooth and punctate, underside in male lacking erect hairs and postmental tubercle; antennal scape and segments 13 of funicle reddish brown, segments 4–7 and club usually dark brown; insertion of antennae on rostrum in apical ¾ in male, antemedian in female; scape slightly curved, gradually thickening towards apex, first segment of funicle elongate, in male slightly shorter than segments 2–4, in females longer than segments 2–4, segment 2 longer than wide, 3–7 transverse, gradually widening to width of club.

PROTHORAX. Sub-trapezoidal (ratio w/l: 1.33), in male sides converging in straight or nearly straight line, in female moderately rounded, deeply bisinuous at base, concavely curved at apex; apical collar at base with a transverse row of black dots; disc in lateral view nearly flat, with a pair of large, deep foveae on either side of middle; integument with double punctuation, glabrous in appearance, with a very short pubescence mainly on sides on basal half; carina in lateral view weak towards base, sharply carinate on collar.

ELYTRA. Widest near middle (ratio w/l: 0.70), in male not tectiform, base of interstria 4 slightly swollen, not raised to a tumour, apical ¾ of suture darker, lacking row of erect setae; interstria 10 in male flat, not inflated and lacking long erect setae, interstria 9 in female costate in basal half; striae as wide as width of interstriae or narrower, gradually fading apicad; stria 9 absent basally, starting from near height of fore coxae; dark stripe on elytra generally present on interstria 6 in basal half and between middle of interstriae 3 or 4 to 8 before declivity.

LEGS. Integument pale yellow, occasionally darkened in fore and middle tibiae, mostly glabrous, with whitish suberect hairs in apical ¾ of tibiae and on tarsus; tibiae bisinuate on ventral side, with a small mucro apically; tarsi with first segment 0.5 × as long as segments 2+3; segment 3 deeply bilobate; segment 4 elongate, as long as 1+2+3; claws free, not apendiculate.

ABDOMEN. Tergites 3–6 undivided on midline; tergite 7 strongly impinging into 6, with a row of granules on basal ¾ and about 15 granules on basal half visible at 50 × magnification; ventrites with short suberect, scattered whitish hairs; in male ventrites 1–2 deeply impressed, depression flanked by longer, semi-erect hairs.

GENITALIA. Penis a little longer than combined length of last three ventrites, body about 2 × as long as wide (ratio w/l: 0.48), symmetrical, with relatively long, tapering apex ( Fig. 4F ); internal sac with a pair of small median sclerites.

Life history

All the specimens collected recently were found on the inflorescences of the oil palm, Elaeis guineensis (Arecaceae) (JH pers. obs.).

Distribution

Angola (Amboim); Cameroon (Bota); Democratic Republic of Congo (Haut-Lopori); Ghana (Egyirkom, Kumasi).

Remarks

Elaeidobius piliventris sp. nov. is distinguished in the male by sides of the ventral impression flanked by longer semi-erect hairs ( Fig. 5 J–K). Females of E. piliventris sp. nov., E. pilimargo sp. nov. and E. singularis cannot be assigned to their specific males based on morphology of the current material of this study. Elaeidobius piliventris sp. nov. is closest to E. pilimargo sp. nov. (2.88% and 2.7–3.0% on COI and COII respectively) and E. singularis (2.6–2.9% on COII).

Figures

Fig. 1. Habitus of males and females of species of Elaeidobius Kuschel, 1952. A. E. bilineatus (Hustache, 1924) comb. nov., Dakar, Senegal. B. E. spatulifer (Marshall, 1950) comb. nov., holotype, Thysville, Democratic Republic of Congo (MRAC). C. E. subvittatus (Faust, 1898), Dakar, Senegal. D. E. kamerunicus (Faust, 1898) comb. nov. (JHAR00209). E. E. pilimargo Haran & Kuschel sp. nov. (JHAR00409). F. E. piliventris Haran & Kuschel sp. nov. (JHAR02182). G. E. plagiatus (Fåhraeus, 1844) comb. nov. (JHAR00272). H. E. singularis (Faust, 1898) comb. nov. (JHAR00283). Scale bars = 1 mm.

Fig. 3. Head and prothorax in lateral view of species of Elaeidobius Kuschel, 1952 (Part 2). A. E. pilimargo Haran & Kuschel sp. nov. (JHAR00409). B. E. piliventris Haran & Kuschel sp. nov. (JHAR02182). C. E. plagiatus (Fåhraeus, 1844) comb. nov. (JHAR00272). D. E. singularis (Faust, 1898) comb. nov. (JHAR00283). Not to scale.

Fig. 4. Penis of males of species of the genus Elaeidobius Kuschel, 1952 in dorsal (left) and lateral (right) view. A. E. bilineatus (Hustache, 1924) comb. nov., Dakar, Senegal. B. E. spatulifer (Marshall, 1950) comb. nov., holotype, Thysville, Democratic Republic of Congo (MRAC). C. E. subvittatus (Faust, 1898), Dakar, Senegal. D. E. kamerunicus (Faust, 1898) comb. nov. (JHAR00209). E. E. pilimargo Haran & Kuschel sp. nov. (JHAR00409). F. E. piliventris Haran & Kuschel sp. nov. (JHAR02182). G. E. plagiatus (Fåhraeus, 1844) comb. nov. (JHAR00272). H. E. singularis (Faust, 1898) comb. nov. (JHAR00283). Scale bars = 100 µm.

Fig. 5. Details of morphology of Elaeidobius spp. A. Pronotum of E. subvittatus (Faust, 1898) in dorsal view showing the flat pronotum and the lateral cuticular expansion near head. B. Pronotum of E. subvittatus (Faust, 1898) in ventral view, showing the trilobate cuticular expansion between the coxae. C. Pronotum of E. plagiatus (Fåhraeus, 1844) comb. nov. in dorsal view showing the fovea on either side of midline. D. Apex of rostrum of E. bilineatus (Hustache, 1924) comb. nov. in lateral view. E. Apex of rostrum of E. subvittatus (Faust, 1898) in lateral view showing the protruding tubercle on underside. F. Elytra of E. bilineatus (Hustache, 1924) comb. nov. in dorsal view. G. Elytra of E. subvittatus (Faust, 1898) in dorsal view. H. Elytra of E. singularis (Faust, 1898) comb. nov. in lateral view. I. Elytra of E. kamerunicus (Faust, 1898) comb. nov. in lateral view. J–K. Abdominal sternites of male of E. piliventris Haran & Kuschel sp. nov. showing the median impression of the first two segments, flanked by a fringe of semi-erect hairs. L. Scutellum of E. plagiatus (Fåhraeus, 1844) comb. nov. in lateral view showing erect setae on tumescent base of interstria 4. M. Pronotum of dark specimens of E. subvittatus (Faust, 1898) in dorsal view. Not to scale.