Xenorthrius perroti Gerstmeier & Eberle 2010, n. comb.

(Figures 41 and 67E)

Orthrius perroti Pic 1939: 18.

Orthrius perroti ab. pallidior Pic 1951: 12.

Specimens examined: Holotype: Vietnam: Tam Dao, Tonkin, H. Perrot; 94; Type; Type; Orthrius perroti n. sp.; Museum Paris, Coll. M. Pic (♀, MNHN).

Others: Vietnam: Mt.Tam Dao, Vinh Phu Prov., N. Vietnam, V.1999 (KSCT). 6.– 10.5.1990 Tam Dao Distr., N Vietnam, 900m, Jan Horák Leg (1ex., NMPC, 1ex., RGCM).

Measurements: (4 specimens measured) Average total length: 9.5mm, range: 8.4–10.5mm, average elytral length: 6.5mm, average elytral width: 2.6mm, average pronotal length: 2.4mm, average pronotal width: 2.1mm, average head width: 1.9mm.

Head: Black, cranium densely vested with longer setae, punctation distinct but sparse; posterior part of clypeus red-brown, margins darkened, distinctly contrasts from head capsule, anterior margin concave centrally, with large punctation and a few long setae laterally, smooth centrally; ventral part wrinkled, smooth centrally; antennae yellow, A4 longer than A3, antennomeres gradually decreasing in length from A4 towards A8, A9 to A11 forming an indistinct club, male antennae reaching slightly beyond base of pronotum when laid back; gular sutures diverging apically, gular process relatively broad.

Thorax: Average pronotal length:width ratio 1.2: 1; pronotum black, vested with short yellowish setae, pronotal arch with distinct punctation, interstices about one diameter of punctures, punctation of pronotum proper denser, interstices smaller than diameter of punctures; prosternum black, smooth; mesosternum black, sparsely vested with yellowish setae; metasternum black, vested with fine setae; large punctation covering whole ventral part of mesepimeron; scutellum round, black.

Elytra: Average length:width ratio 2.5:1; basal quarter black followed by a yellow fascia, postmedian fascia broad, black, near suture and lateral margins more brownish, behind postmedian fascia yellow, extreme apices brownish to black, alongside sutures brown, rectangular subcutaneous structures visible through yellow areas, vested with relatively long erect setae, punctation relatively small, few additional punctation in humeral region between striae 9 and 10, striae 1 to 3 obsolete with beginning of yellow fascia, striae 4 to 9 crossing postmedian black fascia and become obsolete in apical yellow area, striae 10 relatively weak, interstices between and within striae smaller than one diameter of punctures, punctation not rasp-like, interstices smooth, carination absent.

Legs: Yellow, tarsal pulvilli pale; metatibiae curved distally, anterior and posterior face of each tibia carinate, carination red-brown, more distinct on posterior faces and metatibiae.

Abdomen: Ventrites red-brown, punctation sparse; male pygidium subquadrate; male ventrite 5 with slight V-shaped emargination; male ventrite 6 with broad U-shaped emargination. Male genitalia (Fig. 41): Lateral margins of tegmen parallel, sinus deeply U-shaped; phallic plates broad; spicular fork dividing into two branches behind one fifth of length.

Distribution: Vietnam.

Seasonal occurrence: Collected in May.

Unfortunately no specimens of Xenorthrius perroti ab. pallidior were available for this study. Pic (1951) describes the pronotum to be red-brown. The elytra are described to be grayish without distinct fasciae. The specimen he examined was collected in northern Vietnam.