Hylurgops palliatus (Gyllenhal, 1813)

(Figures 15 a, 17a)

Hylesinus palliatus Gyllenhal, 1813:340 (Sweden) Hylastes palliatus, Thomson, 1865: 349

Hylurgops palliatus, Reitter, 1913: 50

Diagnosis. Hylurgops palliatus is distinguished from all the New World species by its smaller size, by the upturned elytral apex (Fig. 15 a), and by the more distinctly impressed discal striae.

Description. Size. Length 2.7–3.4 (avg. 3.1 ± 0.2) mm long, 2.5× longer than wide. Color. Mature adult brown to reddish brown, ventral sclerites dark reddish-brown to black. Frons. Transverse impression shallow; vestiture hair-like setae; longer below mid-impression, length 2–4× diameter of average frontal puncture. Pronotum. Broad 0.8–0.9 (0.9 ± 0), strongly constricted anteriorly (Fig. 17 a), widest anterior to middle; lateral margin rounded, bulging from base to constriction near apical edge; dorsal middle line elevated, extending from base to anterior dorsal impression, surface smooth; discal punctures relatively few for genus, larger punctures twice diameter of smaller; inter-puncture area smooth, or with sparse reticulation; vestiture of short, recumbent, yellowish hair-like setae, long as size of large puncture. Elytra. Anterior margin procurved; striae distinctly impressed, as wide as interstriae except narrower than 2nd; punctures round, less than ½ diameter apart; interstriae convex, surface rugose, minutely punctured (visible at> 115×), each with a median row of erect bristles about 1.5× longer than diameter of strial puncture, rising behind each interstrial granule, separated by distance of two strial punctures. Declivity. Second interstriae widest, indistinctly impressed, 3rd not intersecting 4th; vestiture consisting of three rows of semi-erect whitish to reddish, scale-like setae, close in length as diameter of strial puncture, a median row of erect, thicker, reddish-brown hair-like setae projecting behind each granule, 1.5× the length of a declivital puncture; declivital apex ascending towards the suture. Ventral sclerites. Surfaces shiny, setose-punctate; mesoventrite anterior margin rounded. Legs. Tarsi dark reddish-brown, metatibiae with 2 large socketed teeth before apical angle. Aedeagus. Aedeagus shorter that in New World species, without a dorsal lobe, seminal opening appears more spread apart than in other species (see line drawing in Tsai & Huang 1964).

Gallery. Longitudinal, biramous, slightly sinuate and about 30–50 mm, extending above and below the entrance hole (Davis et al. 2008). Eggs are laid on niches at both sides of the gallery, brood tunnels perpendicular from both sides of the gallery.

Material examined. 70 specimens. JAPAN. Mount Fuji (DEBC), Japan (CNCI). EUROPE. Austria: Amstetten (CNCI, DEBC), Mondseeberg (CNCI), St. Pölten (CNCI). Bosnia and Herzegovina. Zavidovići (CNCI). England. Blandford (DEBC). Germany. München (CNCI). Poland: Bialowiezki NP (DEBC). Russia (CNCI). Czech Republic. Jesenik, Moravia (CNCI). Sweden. Sk. Vånga (CNCI). USA. New York. Nassau Co.: Oyster Bay, Planting field Arbor. (CUIC); Suffolk Co.: Smithown (CUIC). Ohio. Columbian Co.: 8 km SE Lisbon (CUIC); Geauga Co.: 1 km NW Thompson (CUIC), 3.5 km WSW Parkam (CUIC); Lake Co.: 2.2 km W Leroy Center (CUIC), 2 km NE North Madison (CUIC); Mahoning Co.: 5 km W Austintown (CUIC), 1 km W North Lima (CUIC); Portage Co.: 4 km NE Mantua Corners (CUIC), 2 km SSE Garretsville (CUIC); Summit Co.: 1.6 km SW Peninsula (CUIC). Pennsylvania. Crawford Co.: Riceville, SGL-199 (CUIC), Shermanville (CUIC); Erie Co.: Asbury Nature Center (CUIC), Presque Isle State Park (CUIC); Richard Mennetti private land (CUIC), State game land 218 (CUIC).

Nearctic host. Pinus sylvestris

Nearctic distribution. NORTH AMERICA: northeastern USA (established exotic).