Loeblites pseudominor sumatrensis subsp. n., 2024

Jałoszyński, Paweł, 2024, Three new species, one subspecies, and new records of the Oriental genus Loeblites Franz (Coleoptera: Staphylinidae: Scydmaeninae), Zootaxa 5471 (4), pp. 422-432 : 429-430

Loeblites pseudominor sumatrensis subsp. n.

( Figs 4, 8 , 24–28 , 32 )

Material studied. Holotype: INDONESIA (Jambi Province): ♂, two labels: “SUMATRA: Jambi / Mt. Kerinci , 1750- / 1850 m, 11-12.XI. / 1989, Agosti, Löbl / Burckhardt #11” [white], “ LOEBLITES / pseudominor / sumatrensis m. / det. P. Jałoszyński, 2024 / HOLOTYPUS” [red, printed] (MHNG).

Diagnosis. As in nominotypical subspecies (vide supra), but body large (BL> 2.9 mm), pronotum much darker than remaining body parts; distribution: Sumatra.

Description. Body of male ( Fig. 4 ) slender and strongly convex, moderately dark brown with pronotum clearly darker than remaining body parts, covered with light brown vestiture. BL 2.95 mm.

Head in dorsal view transverse, broadest at eyes, HL 0.48 mm, HW 0.65 mm; vertex strongly transverse and evenly convex, anteriorly confluent with frons; frons flattened between prominent supraantennal tubercles; tempora in dorsal view as long as eyes; eyes small, oval, with slightly concave posteroventral margin, finely faceted. Vertex and frons covered with fine, inconspicuous punctures and sparse, moderately long, suberect setae. Antennae long and slender, slightly shorter than BL, AnL 2.40 mm, all antennomeres elongate, as in Fig. 8 .

Pronotum elongate, as wide as head, broadest slightly in front of anterior third; PL 0.83 mm, PW 0.65 mm. Anterior margin broadly rounded, sides strongly rounded in anterior third, posteriorly broadly and weakly constricted; posterior margin nearly straight. Four dorsal antebasal pits large and deep, two lateral pits at each side distinct. Pronotum with small but sharply marked and distinct punctures, on central area separated by spaces as wide as 1–2 puncture diameters; setae long, sparse and suberect.

Elytra more convex than pronotum, oval, broadest distinctly in front of middle; EL 1.65 mm, EW 1.03 mm, EI 1.61. Humeral calli weakly elevated, elongate; apex of each elytron subtriangular, sharply-angled but with blunt tip. Punctures more diffuse and less conspicuous than those on pronotal disc; setae similar to those on pronotum.

Legs long and slender; femora abruptly clavate, dorsal longitudinal grooves on femoral clava complete and with distinct glandular opening at highest site of each femur; all tibiae nearly straight.

Aedeagus ( Figs 24–28 ) elongate but relatively stout; AeL 0.63 mm; median lobe in ventral view equally broad near base and near middle, distal region rapidly narrowing towards truncate apex; endophallus ( Fig. 28 ) with pair of strongly elongate and oblique lateral sclerites ( Fig. 28 ; lsc) distally connected with large and conspicuously darkly pigmented median sclerotized structure, which is strongly transverse and has its distal margin weakly and broadly rounded, proximally lateral sclerites connected with sclerotized median proximal complex, with its proximal margin rounded and strongly convex; parameres shorter than median lobe and their apices only slightly exceeding apex of median lobe, lacking setae.

Female. Not known.

Distribution. Central western Sumatra ( Fig. 32 ).

Etymology. After Sumatra, the type locality.

Remarks. The largest specimens of L. pseudominor from Sabah, Malaysia, and from Bang Lang National Park, Thailand reach 2.50 mm of body length and are uniformly dark brown. A single male from Sumatra, which has the aedeagus with identical endophallus, is remarkably larger (BL 2.95 mm) and has the pronotum clearly darker than remaining body parts. No other species of Loeblites shows such a great variation in the body length (i.e., the largest individuals being over 120% as long as the smallest ones). The indistinguishable aedeagi support a hypothesis of a conspecificity of Bornean, Thai and Sumatran specimens, but the extraordinary body size and a different pigmentation require separating them as two subspecies. More specimens from Sumatra will be required to test this hypothesis. As the spermatheca of the Sumatran subspecies remains unknown, this structure is not included in the diagnosis of the species.

Figures

FIGURE 32. Distribution of nominal species of Loeblites.

FIGURES 1–8. Males of Loeblites anaiensis sp. n. (1, 5); L. umphangensis sp. n. (2, 6); L. pseudominor pseudominor sp. n. (3, 7); and L. pseudominor sumatrensis subsp. n. (4, 8). Dorsal habitus (1–4) and antenna (5–8).

FIGURES 19–28. Loeblites pseudominor pseudominor sp. n. (19–23); and L. pseudominor sumatrensis subsp. n. (24–28). Aedeagus in ventral (19, 21, 24, 26) and lateral (20, 22, 25, 27) views, and close-up of endophallic sclerites in ventral view (23, 28).