Eudesis tenuissima, Jałoszyński, 2024

Jałoszyński, Paweł, 2024, Eudesis tenuissima sp. n. on Italian Peninsula (Coleoptera: Staphylinidae: Scydmaeninae), Zootaxa 5492 (4), pp. 589-595 : 590-592

Eudesis tenuissima sp. n.

( Figs 1‒15 )

Type material. Holotype: ( ITALY): ♂, four labels: “ 8.4.1985 - leg. S. Vit / Ausonia / FR / Mti Aurunci / Lazio - ITALIE” [white, printed and handwritten], “Coll. S. Vit / MHNG - 2021” [white, printed], “ Collection S. VIT” [white with black frame, printed], “ EUDESIS / tenuissima m. / P. Jałoszyński, ‘24 / HOLOTYPUS” [red, printed] ( MHNG).

Diagnosis. Body conspicuously slender, elytra 2.25 times as long as pronotum and ~1.9 times as long as broad; metaventral intermetacoxal process composed of two lateral evenly rounded lobes separated by narrow and deep indentation; endophallus with conspicuously broad and weakly recurved flagellum bearing round distal widening; each paramere with small outer subapical angulate expansion clearly demarcating weakly rounded apical margin.

Description. Body of male ( Fig. 1 ) strongly elongate, strongly flattened, yellowish brown. BL 0.80 mm.

Head ( Figs 2‒3 ) broadest near middle, eyeless, approximately quadrate with weakly rounded lateral margins, HL 0.15 mm, HW 0.15 mm; vertex and frons together about as long as broad; posterior margin of vertex weakly rounded and with indistinct median emargination; supraantennal tubercles weakly elevated, forming short and broad ‘rostrum’. Dorsum of head and most surface of genae impunctate and covered sparsely with short and nearly recumbent setae, posterior margin of genae with modified lanceolate setae directed posteriorly, and anteroventral margin of ‘neck’ region with lanceolate setae directed anteriorly ( Fig. 6 ). Antenna ( Fig. 1 ) slender, AnL 0.30 mm, with trimerous club; scape and pedicel strongly elongate, antennomeres 3–5 each about as long as broad, 6–10 each transverse, 11 slightly shorter than 9–10 combined, only slightly elongate.

Prothorax ( Figs 2–3 ) in dorsal view barrel-shaped, broadest at middle; PL 0.20 mm, PW 0.18 mm. Anterior margin evenly and weakly rounded; anterior corners obtuse-angled and blunt; lateral margins strongly rounded; posterior corners obtuse-angled and each with clearly marked tip; posterior margin weakly and evenly rounded. Lateral carinae accentuated dorsally by short antebasal margin. Pronotal disc impunctate and with evenly distributed short and nearly recumbent sparse setae. Prosternum and hypomera ( Fig. 3 ) with similar setae as those on pronotal disc.

Elytra ( Fig. 4 ) together oval and strongly elongate, broadest slightly in front of middle; EL 0.45 mm, EW 0.24 mm, EI 1.89; humeral denticle weakly developed, posteriorly prolonged by elongate elevation; base of each elytron with two foveae, inner fovea posteriorly confluent with short discal sulcus reaching about 1/3 of elytral length; elytral apices separately rounded. Punctures and setae similar to those on pronotal disc.

Mesoventrite ( Fig. 5 ) with asetose procoxal rests and several long setae behind rests, also mesoventral intermesocoxal process with several conspicuously long setae on its posterior end ( Fig. 7 ).

Metaventrite ( Fig. 5 ) slightly elongate and weakly broadening distally, posterior carinae of mesocoxal rests sharply carinate; anteromedian fovea large and filled with lanceolate setae ( Fig. 7 ); metaventrite distinctly impressed behind anteromedian fovea; metaventral intermetacoxal process composed of two lateral lobes, each with evenly rounded posterior margin, posteromedian indentation separating lobes narrow and anteriorly rounded. Surface of metaventrite sparsely covered with long recumbent setae.

Legs ( Figs 1 , 5 , 8–11 ) moderately long and slender, unmodified. Protarsus with dense ventral pad of tenent setae on tarsomeres 1–3 ( Fig. 8 ), with conspicuously short tarsomeres 1–3, and with tarsomere 4 slightly shorter than 1–3 combined ( Fig. 9 ); mesotarsus ( Fig. 10 ) as long as protarsus, with tarsomeres 1–3 similarly short as those in protarsus, and with tarsomere 4 equal in length to 1–3 combined; metatarsus ( Fig. 11 ) slightly longer than remaining tarsi, with tarsomeres 1–3 distinctly longer than in remaining tarsi, and with tarsomere 4 subequal in length to 1–3 combined.

Abdominal sternites ( Fig. 5 ) with setae similar to those on metaventrite.

Aedeagus ( Figs 12‒15 ) slender, AeL 0.13 mm; median lobe in ventral view bullet-shaped with broadly rounded apex; endophallus with conspicuously thick and weakly recurved flagellum bearing round distal ‘head’; each paramere with distal margin weakly rounded and demarcated from outer margin by small angulate expansion.

Female. Unknown.

Distribution. Central-western region of Italian Peninsula.

Etymology. The specific adjective tenuissima refers to the conspicuously slender body.

Figures

FIGURES 1–3. Eudesis tenuissima sp. n., holotype male. Dorsal habitus (1); head, prothorax and elytral base in dorsal view (2); head, prothorax and anterior region of mesothorax in ventral view (3).

FIGURES 4–5. Eudesis tenuissima sp. n., holotype male. Elytra in dorsal view (4); pterothorax and base of abdomen in ventral view (5).

FIGURES 6–11. Eudesis tenuissima sp. n., holotype male. Modified setae on venter of head (6); modified setae on mesovetral intermesocoxal process and in anteromedian metaventral fovea (7); protarsus in ventral (8) and lateral (9) views; mesotarsus in lateral view (10); metatarsus in lateral view (11).

FIGURES 12–15. Eudesis tenuissima sp. n., holotype male. Aedeagus in ventral (12, 14) and lateral (13, 15) views.