Paraphloeostiba guadalcanalensis, Shavrin, 2024

Shavrin, Alexey V., 2024, Twenty-one new species of Omaliini from the Papuan Region (Coleoptera: Staphylinidae: Omaliinae), with diagnostic and faunistic notes on some species of the genus Paraphloeostiba Steel, 1960, Zootaxa 5424 (3), pp. 251-307 : 273-275

Paraphloeostiba guadalcanalensis sp. n.

( Figs 42 , 57–63 )

Type material. Holotype ♂: ‘SOLOMON IS. | Guadalcanal | Popamanasiu [handwritten] | 5500`[handwritten] | 25 11 [handwritten] 1965 [the last number “5” is handwritten] | 20217 [handwritten] | P. Greenslade’ <printed>, ‘ HOLOTYPE | Paraphloeostiba | guadalcanalensis sp. n. | Shavrin A. V. des. 2024’ <red, printed> ( BMNH).

Paratypes: 7 ♂♂ (one specimen dissected), 11 ♀♀ (one specimen dissected):‘SOLOMON IS. | Guadalcanal Popa-| manasiu 5500`| 25.11.1965 20217 | P. Greenslade’ <printed>, ‘ PARATYPE | Paraphloeostiba | guadalcanalensis sp. n. | Shavrin A. V. des. 2024’ <red, printed> ( BMNH).

Description. Measurements (n=19): HW: 0.44–0.53; HL: 0.27–0.35; OL: 0.15–0.17; TL: 0.05–0.06; AL (holotype): 0.71; PL: 0.33–0.40; PWmax: 0.54–0.63; PWmin: 0.43–0.53; ESL: 0.64–0.77; EW: 0.78–0.89; MTbL (holotype): 0.42; MTrL (holotype): 0.20 (MTrL 1–4: 0.07; MTrL 5: 0.13); AW: 0.76–0.88; AedL: 0.45; BL: 2.07– 3.07 (holotype: 2.32).

Habitus as in Fig. 42 . Body yellow-brown to reddish-brown, with slightly darker apical and lateral portions of head and abdominal tergites (lateral and basal portions of pronotum slightly paler); antennomeres 6–11 brown; femora and tibia yellow-brown; mouthparts, antennomeres 1–5 and tarsi yellowish. Head with very sparse fine punctation, but some paratypes without visible punctation in middle portion; neck without punctures; pronotum with moderately dense, large and deep punctures, with moderately wide impunctate band in middle; elytra with dense punctation, distinctly denser, larger and deeper than that in pronotum, finer around scutellum and along suture; abdominal tergites with distinct, fine and dense punctation, finer and sparser in middle (abdominal tergites of some specimens without visible punctures in middle). Head with very dense and coarse microsculpture, transverse in vertex and isodiametric in middle; pronotum with very dense isodiametric microreticulation, similar to that in middle portion of pronotum, sometimes finer in middle; microsculpture of elytra similar to that in pronotum, sometimes finer along suture; abdominal tergites with dense and coarse isodiametric microreticulation.

Head with flattened middle and slightly elevated infraorbital portions, with moderately wide and deep anteriomedian depressions, 1.4–1.5 times as broad as long, with narrow and moderately deep anteocellar foveae, reaching about level of anterior third of eyes; postocular carina absent. Ocelli moderately small, located slightly below level of posterior margins of eyes; distance between ocellus 1.3–1.4 times as long as distance between ocellus and posterior margin of eyes. Apical maxillary palpomere very long, about three times as long as preapical segment, from basal portion gradually narrowed toward acute apex. Antenna reaching apical margin of elytra when reclined; antennomere 3 distinctly narrower and longer than 2, 4 small, slightly more than twice as long as 3, 5 indisitnctly broader than 4, 6 distinctly longer and significantly broader than 5, 7–9 slightly broader than 6, 10 slightly longer than 9.

Pronotum 1.5–1.6 times as broad as long and 1.1–1.2 times as broad as head, widest slightly above middle, strongly narrowed posteriad, with slightly concave laterobasal margins in front of obtuse hind angles; middle portion with wide and shallow or moderately deep longitudinal impressions, widened basally, with narrow, rounded and slightly elevated ridges in lateroapical portions; lateral portions distinctly depressed, broader in laterobasal portions.

Elytra 1.1–1.2 times as broad as long, 1.9 times as long as pronotum, distinctly broadened posteriad and narrowly impressed along lateral margins.

Abdomen slightly narrower than elytra.

Male. Posterior margin of abdominal tergite VIII truncate ( Fig. 59 ). Posterior margin of abdominal sternite VIII widely and deeply concave ( Fig. 60 ). Aedeagus with wide basal portion, gradually narrowed toward moderately narrow median lobe with small rounded apex; parameres slightly not reaching apex of median lobe, distinctly broadened apicad, with three long apical setae and several moderately long setae on inner margin of each paramere; internal sac long, narrow, with several strongly sclerotized elongate structures in basal portion ( Fig. 57 ). Lateral aspect of the aedeagus as in Fig. 58 .

Female. Posterior margin of abdominal tergite VIII ( Fig. 61 ) and sternite VIII ( Fig. 62 ) rounded. Accessory sclerite with wide basal and narrow long apical portions ( Fig. 63 ). Spermatheca not recognized.

Comparative notes. Based on the general structure of the aedeagus, P. guadalcanalensis sp. n. is similar to P. iriana sp. n., P. riedeli sp. n. and P. conjuncta . Based on the presence of two distinct longitudinal impressions on the pronotum, it is more similar to P. iriana sp. n., from which it can be distinguished by the larger body, slightly shorter parameres with distinctly broader apical portions. It can be distinguished from P. conjuncta by the narrower median lobe and broader apical portions of the shorter parameres, and from P. riedeli sp. n. by the broader apical portions of the aedeagus. Additionally, it can be distinguished from P. conjuncta and P. riedeli sp. n. by the presence of longitudinal impressions and fine punctation of the head. From all these species it differs by the concave laterobasal margins of the pronotum in front of hind angles, details of the morphology of the aedeagus, and the different shape of the female accessory sclerite.

Distribution. Paraphloeostiba guadalcanalensis sp. n. is known only from the type locality in Guadalcanal Island, Solomon Islands.

Etymology. The specific epithet derived from the name of the island where the type specimens were collected.

Bionomics. Specimens were collected at an elevation 1676 m a.s.l. The detailed bionomical data ara unknown.

Figures

FIGURES 39–44. Habitus of Paraphloeostiba: 39–P. coriacea (Western New Guinea), 40–P. iriana (paratype), 41–P. latissima (paratype), 42–P. guadalcanalensis (paratype), 43–P. margineguttata (holotype), 44–P. steeli (holotype). Scale bars: 1.0 mm.

FIGURES 57–63. Paraphloeostiba guadalcanalensis (paratypes): 57–aedeagus, parameral view, 58–aedeagus, lateral view, 59–male abdominal tergite VIII, 60–male abdominal sternite VIII, 61–female abdominal tergite VIII, 62–female abdominal sternite VIII, 63–female accessory sclerite. Scale bar: 0.1 mm.