Euconnus (Rhomboconnus) rhombomiramaranus, Jałoszyński, 2017

Jałoszyński, Paweł, 2017, Euconnus (Rhomboconnus) of Panama (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 4323 (1) : -

Euconnus (Rhomboconnus) rhombomiramaranus sp. n.

( Figs 7 , 15 , 37–38, 45–46, 55)

Holotype: Panama (Bocas del Toro Province): ♂, two labels: "PANAMA, near Miramar / 30/07/2014 / 8,95- 8,99°N / 82,19-82,24°W, / car-net, leg. Tim Struyve" [white, printed], " EUCONNUS / ( RHOMBOCONNUS ) / rhombomiramaranus m. / P. Jałoszyński, '17 / HOLOTYPUS" [red, printed] (MNHW).

Diagnosis. BL <2 mm; head with well-visible, long, moderately dense, suberect setae; tempora strongly narrowing posteriorly with very short, barely discernible posterior portions bent mesally and visible only in lateral or dorsolateral view; pronotum broadest near posterior third and strongly narrowed anteriorly but very weakly so posteriorly; pronotal base with vestigial transverse groove marked at middle as an indistinct, diffuse impression; parameres not broadened in subapical region.

Description. Body of male ( Fig. 7 ) strongly convex, elongate, with moderately long appendages, BL 1.95 mm; cuticle glossy, uniformly dark brown, vestiture slightly lighter than cuticle.

Head ( Fig. 15 ) strongly narrowing posteriorly, broadest at eyes, HL 0.48 mm, HW 0.35 mm; vertex and frons confluent, evenly and weakly convex except frons in front of eyes which steeply declines anteriorly, posterior margin of vertex projecting posteriorly as rounded subtriangular lobe broader than 1/3 of HW; tempora very weakly convex with extremely short, barely noticeable posterior portion bent posteromesally and visible only in lateral or dorsolateral view; supraantennal tubercles barely marked; eyes large, finely faceted and weakly projecting from silhouette of head. Punctures on vertex and frons very fine and inconspicuous; setae sparse but long and suberect; sparse long bristles distributed along posterior margin of vertex and posteriorly on tempora. Antennae slender, AnL 1.03 mm; all antennomeres except III elongate, III slightly transverse; antennomeres VII– XI forming indistinctly delimited club, antennomere XI only slightly longer than X, ~1.7 times as long as broad, indistinctly flattened.

Pronotum ( Fig. 15 ) in dorsal view broadest near posterior third and strongly narrowing anteriorly, but very weakly posteriorly, PL 0.45 mm, PW 0.50 mm; base with indistinct trace of transverse groove marked at middle. Punctures as fine as those on frons and vertex, pronotal disc covered with extremely short and recumbent setae, sides of pronotum with bristles.

Elytra suboval, broadest near middle, EL 1.03 mm, EW 0.83 mm, EI 1.24; apices separately rounded. Punctures and setae similar to those on pronotal disc.

Legs moderately long and slender; protrochanter with slightly expanded ventral margin forming short and broadly subtriangular tooth near middle.

Aedeagus (Figs 37–38, 45–46) stout, AeL 0.38 mm, in ventral view drop-shaped with sides in subapical region rapidly but weakly narrowed; endophallus with three long and one short sclerites ( Fig. 55 ), of which the longest one has its apical portion gradually narrowed and slightly recurved; parameres not broadened in subapical region.

Female. Unknown.

Distribution. Western Panama, Bocas del Toro Province, Chiriquí Grande District.

Etymology. Combination of the subgeneric name Rhomboconnus and the corregimiento of Miramar.

Remarks. Euconnus rhombomiramaranus is a small (<2 mm BL) Rhomboconnus with a rather inconspicuous body shape. However, it is the only known species of this subgenus with only the head bearing long setae, the anterior margin of frons subtriangular in dorsal view, and the pronotal base with a barely discernible trace of the transverse groove marked at middle.

Figures

FIGURES 1 – 8. Dorsal habitus of Rhomboconnus species, males. Euconnus plaumannioloides sp. n. (1); E. timstruyvei sp. n. (2); E. silvafortunensis sp. n. (3); E. rhombopanamensis sp. n. (4); E. rhombocartianus sp. n. (5); E. meteti sp. n. (6); E. rhombomiramaranus sp. n. (7); E. rhomboimitator sp. n. (8).

FIGURES 9 – 16. Head and pronotum of Rhomboconnus species, males, in strictly dorsal view. Euconnus plaumannioloides sp. n. (9); E. timstruyvei sp. n. (10); E. silvafortunensis sp. n. (11); E. rhombopanamensis sp. n. (12); E. rhombocartianus sp. n. (13); E. meteti sp. n. (14); E. rhombomiramaranus sp. n. (15); E. rhomboimitator sp. n. (16).

FIGURES 49 – 56. Endophallic sclerites of Rhomboconnus species in ventral view (not to the same scale). Euconnus plaumannioloides sp. n. (49); E. timstruyvei sp. n. (50); E. silvafortunensis sp. n. (51); E. rhombopanamensis sp. n. (52); E. rhombocartianus sp. n. (53); E. meteti sp. n. (54); E. rhombomiramaranus sp. n. (55); E. rhomboimitator sp. n. (56).