Paraphloeostiba acrolochaoides, Shavrin, 2024

Shavrin, Alexey V., 2024, New species and records of Paraphloeostiba Steel, 1960 and Xanthonomus Bernhauer, 1926 from the eastern Palaearctic, Oriental and Papuan regions (Coleoptera: Staphylinidae: Omaliinae), Zootaxa 5514 (6), pp. 589-597 : 590-591

Paraphloeostiba acrolochaoides sp. nov.

( Figs 1–4 )

Type material. Holotype ♂ (dissected): ‘Stn. No. | 194.’ <printed>, ‘ NEW GUINEA: [underlined by red] | E.Highland Dist., | Mt. Wilhelm, c. 8000ft. | 20–23.ii.1965.’ <printed>, ‘ M.E. Bacchus. | B.M. 1965-120’ <printed>, ‘HOLOTYPE | Paraphloeostiba | acrolochaoides sp. nov. | Shavrin A.V. des. 2024’ <red, printed> ( BMNH) .

Paratypes: 10 ♂♂ (four specimens dissected): same data as the holotype ( BMNH) ; 1 ♂: same data as the holotype, with an additional label: ‘? Phloeonomus [handwritten in black] | sp. [handwritten in black] | P.M. Hammond | det. 1975[“5” - handwritten]’ <printed> ( BMNH) . All paratypes with additional red printed label: ‘ PARATYPE | Paraphloeostiba | acrolochaoides sp.n. | Shavrin A.V. des. 2024’.

Description. Measurements (n=13): HW: 0.40–0.47; HL: 0.24–0.29; OL: 0.11–0.15; AL (holotype): 0.69; PL: 0.26–0.39; PWmax: 0.53–0.60; PWmin: 0.41–0.52; ESL: 0.55–0.67; EW: 0.66–0.79; MTbL (holotype): 0.35; MTrL (holotype): 0.13 (MTrL 1–4: 0.06; MTrL 5: 0.07); AW: 0.65–0.77; AedL: 0.42–0.55; BL: 1.90–2.45 (holotype: 2.19).

Body yellow-brown to reddish-brown, with paler lateral parts of pronotum and darker abdomen; antennomeres 6– 11 brown; mouthparts, antennomeres 1–5 and legs yellow-brown; tarsi yellow. Head with very dense fine punctation, with interspaces in middle about as diameter of one nearest puncture; neck with dense fine punctation; punctation of pronotum similar to that of middle part of head, sometimes indistinctly larger, finer in basal part; scutellum without punctures; elytra with dense, moderately large and deep punctation, sometimes indistinct in middle and apical portions; abdomen with indistinct sparse and fine punctures, invisible in some specimens in middle. Apical part of head with regular, dense and transverse microsculpture; neck with fine transverse or isodiametric meshes; pronotum without microreticulation; scutellum with dense transverse meshes; elytra with dense isodiametric microsculpture, finer and subdiagonal around scutellum and finer along suture in some specimens; abdomen with dense and moderately coarse isodiametric microreticulation.

Head flattened, indistinctly elevated in middle, with wide and moderately deep anteriomedian depressions, 1.6 times as broad as long, with short and deep, sublinear anteocellar foveae, almost reaching level of middle length of eyes; postocular carina missing or indistinct, obtuse, located very close to posterior margin of eyes. Ocelli large, located distinctly below level of posterior margins of eyes; distance between ocelli about as distance between ocellus and posterior margin of eyes or slightly greater. Apical maxillary palpomere about twice narrower and 1.4–1.5 times longer than preapical segment. Antenna reaching basal part of elytra when reclined, with slightly transverse antennomeres 6–7 and distinctly transverse antennomeres 8–10; basal antennomere about twice as long as broad, antennomere 2 shorter and slightly narrower than basal antennomere, 3 distinctly narrower and longer than 2, 4 small, but slightly longer than broad, 5 slightly broader than 4, 6 slightly shorter than 5, 7 distinctly broader than 6, 8–10 slightly broader than 7, apical antennomere 1.7–1.8 times as long as 10, from about middle strongly narrowed toward acute apex.

Pronotum slightly convex, 1.5 times to twice as broad as long, 1.2–1.3 times as broad as head, widest slightly above middle, gradually rounded toward anterior angles and strongly narrowed posteriad toward obtuse posterior angles; laterobasal margins in front of hind margins sometimes widely concave; anterior angles not protruded anteriad; anterior margin straight or slightly concave in middle, slightly shorter than rounded posterior margin; middle portion with very wide and deep semicircular depression (sometimes indistinctly separated in two impressions), deeper in mediobasal portion; laterobasal depressions wide and deep.

Elytra 1.1–1.2 times as broad as long, 1.7 time to twice as long as pronotum, indistinctly broadened posteriad, with narrowly impressed lateral margins; some specimens with slightly impressed mediobasal part; posterior margin straight or widely rounded. Hind wings fully developed.

Metatarsi distinctly more than twice shorter than metatibia.

Abdomen slightly broader than elytra, with two small oval and sometimes indistinct round tomentose spots in middle of abdominal tergite IV; apical margin of abdominal tergite VII with narrow palisade fringe.

Male. Posterior margin of abdominal tergite VIII truncate ( Fig. 2 ). Posterior margin of abdominal sternite VIII widely and deeply concave ( Fig. 3 ). Aedeagus wide, with protruded narrow latero-apical parts; median lobe moderately wide, from about middle gradually narrowing toward small rounded apex; apical parts of aedeagus with paired curved pocesses connected with median lobe and narrow latero-apical portions; parameres longer than apex of median lobe, with narrow apical parts, with two moderately short apical setae and five to six setae along inner preapical margins on each paramere; internal sac complicated, wide and moderately long, with two large and wide sclerotized structures in apical and two elongate structures in basal portions ( Fig. 1 ). Lateral aspect of the aedeagus as in Fig. 2 .

Female unknown.

Comparative notes. Based on the general shape of the body and the aedeagus, and the presence of median depression on the pronotum, P. acrolochaoides sp. nov. is similar to P. vitiosa Shavrin, 2024 , recently described from Western New Guinea. The new species can be distinguished from it by the more transverse antennomeres 8–10, the presence of long transverse processes in medioapical part of the aedeagus, narrower median lobe and parameres with finer apical setation, and different structure of the internal sac.

Distribution. Paraphloeostiba acrolochaoides sp. nov. is known only from the type locality in Wilhelm Mt. in Papua New Guinea.

Etymology. The name of the new species is derived from the fact that the apical part of the aedeagus is somewhat similar to some species of the Holarctic Acrolocha Thomson, 1858 (Omaliini).

Bionomics. Specimens were collected at elevation about 2400 m a.s.l. The detailed bionomical data are unknown.

Figures

FIGURES 1–4. Paraphloeostiba acrolochaoides: 1—aedeagus, parameral view, 2—aedeagus, lateral view, 3—male abdominal tergite VIII, 4—male abdominal sternite VIII. Scale bars: 0.1 mm.