Euconnus (Rhomboconnus) maya, Jałoszyński, 2020

Jałoszyński, Paweł, 2020, Euconnus (Rhomboconnus): redescriptions of species described by Schaufuss and Sharp, and descriptions of five new Mexican species (Coleoptera, Staphylinidae Scydmaeninae), Zootaxa 4759 (2), pp. 209-222 : 220-221

Euconnus (Rhomboconnus) maya sp. n.

( Figs 8 , 15 , 49–53 )

Holotype: Mexico (Chiapas State): ♂, two labels: “Mex.: Chis; Palenque / 2.-23.VII.1983 / S. & J. Peck, 80 m / 2nd growth FIT” [white, printed], “ EUCONNUS / ( RHOMBOCONNUS ) / maya m. / P. Jałoszyński, 2020 / HOLO- TYPUS ” [red, printed] ( MHNG).

Diagnosis. Head in male stout, with short and rounded posterior margin of vertex; tempora distinctly rounded and strongly narrowing posterad; pronotum subconical with rounded sides, broadest in posterior third, with sharply marked transverse antebasal groove distinctly deepened at each end and with short but distinct sublateral carinae; dorsum moderately densely setose, setae conspicuously broadened, flattened, curved and contrastingly light compared to dark cuticle; antennomeres VII–X slightly elongate (X the longest); aedeagus with ventral plate in distal half nearly rod-like, parallel-sided and narrow; endophallus with long and moderately broad sclerites, of which the longest is pointed at apex, with strongly asymmetrical distal portion.

Description. Body of male ( Fig. 8 ) strongly convex and relatively stout, with moderately long and slender legs and with conspicuously long, moderately slender antennae, BL 2.09 mm; cuticle glossy, dark brown with reddish hue, vestiture contrastingly lighter than cuticle, yellowish.

Head ( Fig. 15 ) stout, strongly narrowing posteriorly, broadest at eyes, HL 0.49 mm, HW 0.43 mm; vertex and frons confluent, together evenly convex, posterior margin of vertex short and rounded; tempora distinctly rounded, only 2.5 × as long as eyes in dorsal view; supraantennal tubercles barely marked; eyes moderately large, finely faceted and relatively strongly projecting from silhouette of head. Punctures on vertex and frons fine and inconspicuous; vestiture composed of two kinds of setae: fine, recumbent, numerous short setae barely discernible under magnification 100 × distributed on median area of frons and anteromedian area of vertex, and conspicuously broad and flattened, curved, long and suberect setae on sides and in posterior region of head, additionally posterior portion of each temple with several dense thick setae, obscured by long dorsal setae. Antennae slender and strikingly long, AnL 1.45 mm; all antennomeres except III distinctly to strongly elongate, III slightly transverse, XI nearly slightly shorter than IX–X together, about twice as long as broad; distal portion of antenna from antennomere VIII gradually flattened.

Pronotum ( Fig. 15 ) in dorsal view subconical with relatively broad anterior margin and rounded sides, broadest in posterior third and moderately strongly narrowing anterad, PL 0.45 mm, PW 0.55 mm; anterior margin nearly straight, posterior margin indistinctly bisinuate, base with sharply marked transverse groove distinctly deepened at each end, and with short and distinct sublateral carinae extending from posterior margin to slightly beyond the level of transverse groove. Punctures inconspicuous; disc covered with modified setae similar to those on head, additionally sides with long and dense thick bristles.

Elytra together suboval, broadest near middle, EL 1.15 mm, EW 0.95 mm, EI 1.21; apices rounded together. Punctures on elytral disc slightly more distinct than those on head and pronotum but superficial and inconspicuous; disc covered with modified setae similar to those on head and pronotum.

Legs moderately long and slender; unmodified.

Aedeagus ( Figs 49–53 ) stout, AeL 0.40 mm, in ventral view drop-shaped with apical region rapidly narrowed; endophallus with moderately broad complex of sclerites ( Fig. 53 ), of which the longest is strongly asymmetrical in apical region, with slender, pointed apex; parameres slender, each with three long apical and subapical setae.

Female. Unknown.

Distribution. Southern Mexico.

Etymology. After the indigenous Maya people and culture of southern Mexico (noun in apposition).

Remarks. This remarkable species differs from all congeners in the dense vestiture of modified, broadened, flattened and curved yellow setae, strongly contrasting with dark cuticle.

Figures

FIGURES 1–8. Dorsal (1–3, 5–8) and lateral (4) habitus of Euconnus (Rhomboconnus). Euconnus cavifrons (L.W. Schaufuss) (1); E. giraffa Sharp (2); E. agiraffa sp. n. (3–4); E. oaxacanus sp. n. (5); E. bicarinatus sp. n. (6); E. cordobanus sp. n. (7); E. maya sp. n. (8).

FIGURES 9–15. Head and pronotum of Euconnus (Rhomboconnus) in dorsal view. Euconnus cavifrons (L.W. Schaufuss) (9); E. giraffa Sharp (10); E. agiraffa sp. n. (11); E. oaxacanus sp. n. (12); E. bicarinatus sp. n. (13); E. cordobanus sp. n. (14); E. maya sp. n. (15). Abbreviations: ami, anteromedian impression; abg, antebasal groove; abp, antebasal pit; slc, sublateral carina.

FIGURES 44–53. Aedeagus in ventral (44, 46, 49, 51) and lateral (45, 47, 50, 52) views, and endophallic sclerites in ventral view (48, 53) of Euconnus cordobanus sp. n. (44–48); E. maya sp. n. (49–53).