Scaphisoma jacqi Löbl & Ramage, 2022

Ramage, Thibault & Löbl, Ivan, 2022, A new species of Scaphisoma Leach from the Society Islands with commentary on Staphylinidae of the French Polynesia (Coleoptera, Staphylinidae, Scaphidiinae), Bulletin de la Société entomologique de France 127 (1), pp. 55-60 : 57-59

Scaphisoma jacqi Löbl & Ramage , n. sp.

http://zoobank.org/F092C8CB-A78E-46E8-9CF2-0FEFE201450E

HOLOTYPE: ♂, French Polynesia, Society Islands, Raiatea Island, Faaroa Valley , 16°50’51.2’’S 151°25’47.7’’W, 57 m, Malaise trap, 1-8.III.2021, leg. Frédéric Jacq; MHNG-ENTO 0093802 ( MHNG) .

Description. – Length 1.28 mm, width 0.87 mm. Head and pronotum blackish ( fig. 1-2 ). Elytra blackish along bases, suture, lateral margins and on transverse area posterior of mid-length and anterior apical sixth. Area anterior of blackish transverse band dark reddish brown, apical sixth yellowish. Venter of thorax and ventrite I blackish, following abdominal segments and appendages light, ochraceous or yellowish.

Pronotum not microsculptured, with lateral margins evenly arcuate, lateral margins carinae visible in dorsal view, lateral striae finely punctate, discal punctation dense and fine, consisting of well delimited punctures much smaller than puncture intervals. Exposed tip of scutellum minute, triangular. Elytra not microsculptured, moderately narrowed apically, with lateral margins nearly evenly rounded, lateral margins striae impunctate near bases, densely punctate posterior basal third of lateral length; apical margins rounded, inner apical angles situated in level with outer apical angles; sutural margin not raised, sutural striae starting at level of scutellar tip, straight, gradually converging apically; adsutural areas flat, combined 0.16 mm wide at level of scutellar tip, each with three irregular puncture rows in basal third reduced to a single puncture row in apical third. Hind wings fully developed. Hypomeron not microsculptured, smooth, lacking traces of punctation. Mesepimeron nearly four times as long as wide and slightly longer than interval to mesocoxa. Median part of metaventrite slightly convex, lacking impressions. Lateral areas of metaventrite not microsculptured, without antecoxal puncture row, sparsely and very finely punctate. Submesocoxal area about 0.05 mm, as fourth of interval to metacoxa. Submesocoxal line arcuate, fairly coarsely punctate. Metanepisternum flat, narrowed anteriad, with slightly sinuate suture, not microsculptured, with punctation as that on sides of metaventrite. Tibiae straight. Abdomen with transversely striate microsculpture. Ventrite I as finely and sparsely punctate as lateral parts of metaventrite; submetacoxal area about 0.08 mm, as two thirds of interval to apical margin; submetacoxal line convex, fairly coarsely punctate.

Male characters. Protarsomeres I to III distinctly widened, narrower than apices of tibiae. Mesotarsomeres not widened.Apical process of ventrite VI triangular, acute, 0.02 mm long.Aedeagus ( fig. 3-5 ) 0.49 mm long. Basal bulb large, about twice as long as apical process, with robust, ventrally prominent articular process. Ventral branch of apical process sinuate, in lateral view, lacking denticles. Parameres sinuate in lateral view, arcuate and narrowed posterior of mid-length in dorsal view. Internal sac with two apical bunches of long, straight denticles, single large, straight mesal denticle and two basal vesicles containing dense, curved denticles appearing in dorsal view as irregularly striate structures.

Etymology. – The specific epithet refers to the family name of the collector of the species, Frédéric Jacq, a great naturalist and photographer, and for his huge contribution to the knowledge of the entomofauna of French Polynesia. The species epithet is to be treated as a noun in the genitive case.

Habitat. – The Malaise trap ( fig. 6-7 ) was set along an abandoned trail, in a Talipariti tiliaceum (L.) Fryxell secondarized forest, degraded with Syzygium cumini (L.) Skeels , Ardisia elliptica Thunb. , and Passiflora laurifolia L. The herbaceous understory was composed of Sphagneticola trilobata (L.) Pruski , Christella sp. , Zingiber zerumbet (L.) Roscoe ex Sm. , Nephrolepis hirsutula (G.Forst.) C.Presl and Centotheca lappacea (L.) Desv.

Comments. – The species is a member of the Scaphisoma haemorrhoidale group, defined by the aedeagi symmetrical with a trifid apical process, narrow, simple parameres usually lacking lobes and a complex internal sac lacking flagellum ( LÖBL, 1970). The aedeagal characters suggest relationships with S. perkinsi Scott, 1908 , described from Hawaii, redescribed and subsequently recorded from the Bonin (Ogasawara) Islands ( LÖBL, 1981). The new species may be readily distinguished from S. perkinsi by the pattern of elytral colour (the latter has elytra uniformly black between bases and the light apical area) and by the internal sac of the aedeagus bearing an elongate mesal denticle absent from S. perkinsi , and lacking an elongate V-shaped sclerite.

Figures

Fig. 1-2. – Scaphisoma jacqi n. sp. – 1, Dorsal view. – 2, Lateral view. Scale = 0.5 mm.

Fig. 3-5. – Scaphisoma jacqi n. sp., aedeagus. – 3, Median lobe and parameres in dorsal view, scale = 0.1 mm. – 4, Aedeagus in lateral view, same scale. – 5, Internal sac in dorsal view, scale = 0.05 mm.

Fig. 6. – The site in Faaroa Valley, Raiatea Island.

Fig. 7. – Maps of French Polynesia and Raiatea Island.