Omotrachelus parallelus Borovec, 2023

Borovec, Roman, 2023, New data on Omotrachelus Kolbe, with description of five new species (Coleoptera; Curculionidae; Entiminae; Cneorhinini), Zootaxa 5357 (4), pp. 502-514 : 510-511

Omotrachelus parallelus Borovec sp. nov.

Figs (4, 9, 15, 21)

http://zoobank.org/ urn:lsid:zoobank.org:act:C9B6181F-A225-4754-9670-CB0DC365332E

Type locality. Togo, Fazao-Malfakassa NP, 4 km S of Point de vue campsite .

Type material. Holotype: ♁, Togo, Fazao-Malfakassa NP, 4 km S of Point de vue campsite, Swamp Forest , 8°46′25.8″ N, 0°49′8.9″ E, 19–21.viii. 2018, 495m, Leaf litter/Winkler, Aristopahnous, M., Geiser, M., Moretto, P., Sanbena, B. leg. ANHRT: 2018.31, BMNH(E) 2018-148 ( BMNH) . Paratypes: 57 specs., same data as holotype ( BMNH, CMNC, RBSC) ; 1 ♁, same data as holotype, Malfakassa NP, but Mare aux crocodiles campsite, Sudanian savannah/gallery forest , 8°44′58.8″ N, 0°48′51.8″ E, 26.viii-8.ix. 2018, 505 m, General Coll. ( BMNH); 2 spec., same data as holotype, Malfakassa NP, but Point de vue campsite, Sudanian savannah , 8°48′50″ N, 0°49′3.2″ E, 16–24.viii2018, Gen. Coll. ( BMNH); 1 ♀, Nigeria: Fashola, W State, XI.1974, J. T. Medler coll. ( BMNH) .

Description. Body length 2.38–3.03 mm, holotype 2.56 mm. Body densely covered with large, rounded, finely striate, on elytra imbricated appressed scales, 3–4 across width of one interstria. All elytral interstriae with conspicuous, dense row of wide, spatulate, semi-erect setae, bent posteriad, slightly longer than half the interstria width and about as wide as half the interstria width, distance between two setae about twice the length of one seta. Setae on pronotum and head with rostrum similar, only slightly shorter and narrower than elytral ones, densely irregularly scattered. Scapes, femora and tibiae with slenderer, subspatulate, semi-appressed short setae, inconspicuously prominent from outline.

Rostrum ( Fig. 15 ) short and robust, 1.11–1.14× as wide as long, in dorsal view in very short basal part enlarging anteriad, then slightly evenly tapering anteriad with straight sides, at base 1.09–1.15× as wide as at apex; in lateral view almost flat, in apical part curved downwards. Epifrons at base almost as wide as rostrum, distinctly tapering anteriad with concave sides, at base 1.38–1.45× as wide as at apex, between antennal insertions distinctly narrower than space between eyes, dorsally longitudinally depressed. Frons very short, glabrous. Epistome short, V-shaped. Antennal scrobes in dorsal view hardly visible only in apical and basal part; in lateral view straight, narrow, directed to ventral margin of eye and teaching it. Vertex wide, flat. Eyes small, almost flat, not prominent from dorsal outline of head; in lateral view oval, placed near the middle of head.

Antennae ( Fig. 4 ) short and slender; scape almost straight, 4.7–4.8× as long as wide, in apical half weakly evenly enlarging apicad, at apex 0.8–0.9× as wide as club. Funicle segment 1 2.0–2.2× as long as wide and 1.4–1.6× as long as segment 2, this is 1.9–2.1× as long as wide; segment 3 1.1× as wide as long; segments 4–6 1.3–1.4× as wide as long; segment 7 1.4–1.5× as wide as long; club 1.6–1.8× as long as wide.

Pronotum ( Fig. 4 ) short and wide, 1.71–1.76× as wide as long, widest behind midlength with strongly rounded sides, distinctly more tapering anteriad then posteriad, behind anterior margin constricted and in lateral view flat, in posterior two thirds distinctly domed; base arched.

Elytra ( Fig. 4 ) long oval, 1.29–1.32× as long as wide, behind base in short part constricted, widest slightly before midlength, with subparallel sides at basal half, apically broadly rounded; base arched; interstria 9 with low subhumeral bump visible in dorsolateral view. Odd interstriae slightly wider than even ones; striae deep and distinct, somewhat punctured.

Protibiae short and robust, 3.8–4.0× as long as at midlength wide, apically obliquely subtruncated, densely fringed by yellow setae, inner margin not denticulate. Tarsi with segment 2 1.2× as wide as long; segment 3 1.3– 1.4× as wide as long and 1.6–1.7× as wide as segment 2; onychium subequal to segment 3 in length.

Penis ( Fig. 15 ) long, 3.11–3.47× as long as wide, subparallel-sided in basal two thirds with straight or slightly rounded sides, apical portion elongated with concave sides, tip broadly rounded; in lateral view slender, weakly regularly curved, tip elongate, straight; temones almost twice as long as body of penis. Endophallus with two halfmoon-shaped sclerites, different in size.

Spermatheca ( Fig. 21 ) with cornu short and apically broadly rounded; corpus elongated; ramus rounded, shorter than wide; collum elongate, longer than wide, straight, slightly tapering apicad. Sternite VIII with long and slender apodeme; plate umbrella-shaped, moderately small. Gonocoxites slender, evenly tapering apicad with long apical styli.

Biology. All specimens were collected from leaf litter using Winkler equipment, in swamp forest.

Etymology. The subparallel-sided elytra suggested the Latin name of this new species.

Remarks. Omotrachelus parallelus clearly differs from all other species of the genus in its small oval eyes, in lateral view placed near the middle of the head a long distance from the dorsal margin of the head, while all other Omotrachelus species have eyes large, subcircular, dorsally placed, in lateral view almost touching the dorsal margin of the head. Other specific characters of this species are as follows: semi-erect elytral setae short, conspicuously spatulate, epifrons at base as wide as rostrum, protibiae very short and robust, and tip of penis enlarging in dorsal view and distinctly curved in lateral view.

Figures

FIGURES 11–21. 11–16: penis in dorsal and lateral view. 11. Omotrachelus geiseri. 12. O. kaniai. 13. O. angulatus. 14. O. longirostris. 15. O. parallelus. 16. O. thoracomimus. 17–21: spermatheca. 17. O. geiseri. 18. O. kaniai. 19. O. angulatus. 20. O. longirostris. 21. O. parallelus. Scale 0.125 mm for 20, 21; 0.25 mm for 17–19; 0.50 mm for 11, 12, 14–16; 1.00 mm for 13.

FIGURES 1–4. Dorsal habitus. 1. Omotrachelus geiseri. 2. O. kaniai. 3. O. longirostris. 4. O. parallelus. Not to scale.