Plaumanniola cayennensis, Jałoszyński, 2018

Jałoszyński, Paweł, 2018, A new species of Plaumanniola Costa Lima in French Guiana (Coleoptera: Staphylinidae), Zootaxa 4508 (3), pp. 431-434 : 432

Plaumanniola cayennensis sp. n. ( Figs 1–9 )

Material studied. Holotype: FRENCH GUIANA: ♂, two labels: "NLT(LP) x3: Amazon Natu- / re Lodge (282m), Kaw mts / 45 km SW from Cayenne / [FR. GUIANA] / N04° 33'59'' W52° 12'42'' / 3-4.ii.2017, S.Nomura leg." [white, printed], " PLAUMANNIOLA / cayennensis m. / P. Jałoszyński, '18 / HOLOTYPUS " [red, printed] ( NSMT) . Paratypes: 3 ♂♂, same data as for holotype ( NSMT, cPJ) .

Diagnosis. Head slightly broader than long and much narrower than pronotum; pronotum only slightly narrower than elytra, broadest near middle and with sides strongly, evenly rounded; antenna with club composed of five antennomeres, of which IX–XI are compactly assembled, and VII is only slightly broader than VI; legs weakly flattened, with mesotrochanter in males bearing a long ventral projection; aedeagus in ventral view slender and rapidly narrowed distad, each paramere with two long subapical setae near apex and one short seta inserted far from apex.

Description. Body of male ( Figs 1–2 ) stout and weakly convex, brown, covered with light brown vestiture. BL 1.86–1.95 mm.

Head ( Fig. 3 ) in dorsal view subtrapezoidal, strongly flattened, broadest clearly behind eyes, HL 0.38–0.40 mm, HW 0.49–0.50 mm; vertex strongly transverse and weakly, evenly convex, anteriorly confluent with weakly convex frons; tempora in dorsal view slightly shorter than eyes; supraantennal tubercles absent; eyes large and coarsely faceted. Vertex and frons covered with distinct but small punctures separated by spaces 2–3 times as wide as diameters of punctures, and with sparse, long, suberect setae, posteriorly replaced by thick bristles; cuticle of head dorsum with fine and diffuse microreticulation. Antennae ( Fig. 3 ) relatively long and slender, with flattened pentamerous club about as long as half AnL, AnL 0.80–0.83 mm, antennomeres I and II elongate, III–X distinctly transverse, VII only slightly broader than VI, XI indistinctly shorter and much narrower than IX–X, about twice as long as broad; club with sparse and conspicuously long erect setae.

Pronotum more convex than head, broadest near middle; PL 0.46–0.50 mm, PW 0.65–0.68 mm. Anterior margin with a narrow median emargination, anterior corners broadly rounded and projecting anterad, sides strongly and evenly rounded, posterior corners strongly obtuse-angled and barely discernible, posterior margin arcuate. Microsculpture similar to that on head but even more diffuse and superficial, setae and punctures as those on frons and vertex, lateral bristles only slightly thicker than setae on disc.

Elytra more convex than pronotum, oval, broadest between middle and anterior third; EL 1.00– 1.08 mm, EW 0.83– 0.85 mm, EI 1.21–1.30. Elytral base with weakly elevated, small humeral calli. Punctures similar to those on head and pronotum; setae distinctly longer, strongly erect; microsculpture absent.

Legs only weakly flattened, robust; mesotrochanters modified ( Fig. 4 ), each with a ventral rod-like projection.

Aedeagus ( Figs 5–8 ) elongate and relatively slender; AeL 0.40 mm; median lobe in ventral view broadest near basal third and gradually narrowing to subapical region, where it is narrowed rapidly to form a subtrapezoidal apex; internal armature asymmetrical and complicated; parameres slender, each with 3 subapical setae, of which two long and curled ones are inserted near apex, and one short and straight far from the apex.

Female. Unknown.

Distribution. Northeastern French Guiana ( Fig. 9 ).

Etymology. Locotypical, after the capital city of French Guiana.

Remarks. Plaumanniola cayennensis is externally most similar to the Bolivian P. simplicissima ; these species share not only the adult body shape, but also the antennal structure, with antennomeres IX–XI compactly assembled and VII– VIII loosely assembled, the basal stalks of the latter exposed, as in proximal antennomeres. The aedeagi, however, differ markedly, that of P. cayennensis being much more slender. The aedeagus of P. cayennensis is most similar to that of P. octosetosa , both being most slender of the copulatory organs found among species of Plaumanniola . Externally, these species differ remarkably, with the body of P. octosetosa being Euconnus -like, i.e., with a subtrapezoidal pronotum broadest near base, and that of P. cayennensis strongly transverse and broadest near middle.

Figures

FIGURE 9. Distribution of Plaumanniola.

FIGURES 1–8. Plaumanniola cayennensis sp.n. Dorsal (1) and lateral (2) habitus of male; head in dorsal view (3); middle leg (4); aedeagus in ventral (5, 7) and lateral (6, 8) views.