Euconnus (Cladoconnus) sagittarius Jałoszyński, 2024, sp. nov.
Creators: name: Jałoszyński, Paweł
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Euconnus
Euconnus sagittarius

description: Euconnus (Cladoconnus) sagittarius sp. nov.
(Figs 2, 4, 9–12)
Material studied. Holotype: ♂ (CHINA: Gansu): "CHINA: S-Gansu [CH12-07] / Mts. 36 km SE Longnan, / 33°13’20’’N, 105°15’10’’E, 2170 m, / N-slope with shrubs and scattered / coniferous trees, litter & mushrooms / sifted, 31.VII.2012, leg. M. Schülke " [white, printed], " EUCONNUS / (CLADOCONNUS) / sagittarius m. / P. Jałoszyński, 2024 / HOLOTYPUS" [red, printed] (MNHB). Paratypes: 2 ♀♀, same data as for holotype (cPJ, MNHB).
Diagnosis. Ventral plate of median lobe broad and arrowhead-shaped with proximal and distal regions subequal in width; endophallus with three asymmetrical sclerites, of which two are extremely long and one short and situated in proximal region of endophallus, in ventral view left long sclerite weakly curved except strongly curved apex, median long sclerite bifurcate, in distal half divided into two slender and pointed arms parallel to long axis of aedeagus, and right short sclerite bifurcate L-shaped with distal arm directed distally and laterally, and proximal arm transverse in relation to long axis of aedeagus and directed laterally.
Description. Body of male (Fig. 2) elongate but moderately slender, moderately convex, with long appendages, BL 1.68 mm; cuticle glossy, pigmentation dark brown, head and pronotum slightly darker than elytra, vestiture of setae light brown.
Head in dorsal view round, broadest across eyes, HL 0.30 mm, HW 0.33 mm; tempora in dorsal view nearly twice as long as eyes, but in lateral view each temple subequal to longest diameter of eye; vertex and frons confluent, weakly and evenly convex, vertex slightly bulging posterodorsally; supraantennal tubercles small but distinctly elevated. Eyes moderately large, coarsely faceted, distinctly but not strongly projecting laterally from head silhouette, in lateral view oval. Punctures on vertex and frons inconspicuous, small and sparse; setae short and sparse, suberect, thick bristles present on vertex and tempora. Antennae (Fig. 4) slender, indistinctly longer than half BL, AnL 0.98 mm; antennomeres 1–2 each elongate, 3 indistinctly elongate, 4–7 each about as long as broad, 8 modified, at base broader than 7, elongate, with its mesal margin concave and with strongly projecting mesal proximal corner, mesal distal corner weakly projecting, antennomere 9 modified, indistinctly longer than 8, with its mesal margin concave and its mesal distal corner distinctly projecting, 10 distinctly shorter than 9, about as long as broad, 11 longer than 10 but much shorter than 9–10 combined, about twice as long as broad.
Pronotum broadest in front of middle, PL 0.40 mm, PW 0.36 mm; anterior margin arcuate, lateral margins rounded in anterior half and sinuate in posterior half, posterior corners slightly obtuse-angled, blunt. Pronotal base with barely marked median longitudinal wrinkle separating pair of large pits, each posterior corner with short and fine sublateral carina and pit between carina and lateral margin. Punctures on pronotal disc inconspicuous; setae moderately dense and long, suberect and mixed with thick bristles.
Elytra oval, broadest slightly in front of middle, EL 0.98 mm, EW 0.73 mm, EI 1.34; elongate adsutural area in anterior third flattened, but not impressed; basal impressions deep, humeral calli prominent, elytral apices separately rounded. Punctures on elytral disc inconspicuous, superficial; setae longer than those on pronotum, moderately dense and suberect to erect. Hind wings long, functional.
Legs long and slender, unmodified.
Aedeagus (Figs 9–12) stout, drop-shaped, AeL 0.38 mm; median lobe broadest near middle, rapidly narrowed in distal half, with dorsal apical plate elongate subtriangular with convex lateral margins; ventral apical plate arrowhead-shaped with remarkably large distal region; endophallus with three asymmetrical sclerites, of which two are extremely long and one short and situated in proximal region of endophallus, in ventral view left long sclerite weakly curved except strongly curved apex, median long sclerite bifurcate, in distal half divided into two slender and pointed arms parallel to long axis of aedeagus, and right short sclerite bifurcate L-shaped with distal arm directed distally and laterally, and proximal arm transverse in relation to long axis of aedeagus and directed laterally. Setae on dorsal wall short and visible only in lateral view (Fig. 12); parameres broad and short, each with two long apical setae.
Female. Similar to male but slightly larger, antennae shorter in relation to BL and with unmodified antennomeres 8 and 9, and with distinctly smaller eyes, in dorsal view tempora almost 3 times as long as eye. BL 1.73–1.75 mm; HL 0.33–0.35 mm, HW 0.33–0.35 mm, AnL 0.85 mm; PL 0.43 mm, PW 0.36–0.38 mm; EL 0.98 mm, EW 0.70– 0.73 mm, EI 1.34–1.39.
Distribution. Central China: SE Gansu.
Etymology. The name sagittarius (noun in apposition) refers to the ventral plate of the aedeagus being shaped like an arrowhead.
Remarks. Euconnus sagittarius has the ventral plate of the median lobe arrowhead-shaped, and this structure is similar to those known in the members of the E. ussuriensis species group: E. ussuriensis Kurbatov, 1988 (Russian Far East), E. nakahamai Hoshina & Miyata, 2018 (in Hoshina et al. 2018) (Shikoku), and E. rudimentalis Jałoszyński, 2019b (South Korea). However, in these species the ventral plate of the aedeagus has the arrowhead apex less than half as wide as its base, while in E. sagittarius the distal region is almost as wide as the proximal portion. Moreover, the distal arrowhead region in E. sagittarius is much longer than in the remaining species, and the shapes and arrangement of endophallic sclerites is different. Interestingly, males of E. pingpong and E. sagittarius have almost all measurements identical, with the exception of AnL, which is slightly greater for the latter species. They differ externally in antennal modifications, E. sagittarius having more concave mesal margins of antennomeres 8 and 9, and their aedeagi are remarkably different.
description: Published as part of Jałoszyński, Paweł, 2024, Subgenera Cladoconnus Reitter and Tetramelus Motschulsky of Euconnus Thomson discovered in China (Coleoptera, Staphylinidae, Scydmaeninae), pp. 232-256 in Zootaxa 5514 (3) on pages 235-237, DOI: 10.11646/zootaxa.5514.3.2, http://zenodo.org/record/13849780