Staphylinus cruentus Olivier 1794:27

Gusarov, V. I., 2001, Quedius Cruentus (Olivier) (Coleoptera, Staphylinidae), A Palaearctic Species New To North America, The Coleopterists Bulletin 55 (3), pp. 374-377 : 374-376

Staphylinus cruentus Olivier 1794:27 .

Specimens Examined. CZECH REPUBLIC: 1 Ƌ, Prague; RUSSIA: 1 ♀, Belgorod reg., Borisovka , 20. VI.1982 ; UKRAINE: Crimea: 1 Ƌ, Simferopol’ Distr., Eastern slope of Chatyr­Dag Mt. , 1,000 m, 11. VI.1984, V. Gusarov leg. ; 1 ♀, Belogorsk Distr., Karasevka , 1. VI.1978, S.Mosyakin leg. ; 1 ♀, Sevasto­ pol’, Orlinoye , 12.X.1990, V. Gusarov leg. ; U.S.A.: 1 Ƌ, New York: Orange Co., 8 km S New Windsor, Black Rock Forest , 23–25. V.1998, V. Gusarov leg.

Description. Length 7.5–10.5 mm. Body black; mouthparts, 2–5 basal segments of antennae and legs reddish; elytra red or dark brown with reddish sutural and apical margins or black; sometimes apical margin of abdominal segments 3–6, apical half of segment 7 and entire segment 8 reddish.

Head slightly wider than long (measured from nuchal ridge; 1.2–1.3 times in males; 1.1–1.2 in females), eyes 1.1–1.5 times longer than temples (seen from above). Upper surface with fine microsculpture of transverse waves and additional scarce and fine micropunctation. Posterior frontal puncture closer to posterior margin of eye than to nuchal constriction. Second antennal segment 1.4 times longer than wide, third twice as long as wide and 1.4 times longer than second, fourth segment quadrate, fifth 1.2, sixth 1.3, sixth­ninth 1.6, tenth 1.4 times wider than long.

Pronotum slightly wider than long (1.1–1.2), wider than head (1.2–1.3). Microsculpture (including anterior angles) as on head. Dorsal rows each with three punctures, sublateral rows with three­five punctures, posterior puncture located behind level of large lateral puncture. Scutellum impunctate with microsculpture of transverse waves.

Elytra measured from humeral level as wide as long, 1.6 times wider than long if measured from apex of scutellum. No visible microsculpture at ×50. Punctation strong and dense, punctures separated by intervals equal 1/2 their diameter.

Abdominal tergites without visible microsculpture at ×50, punctated less strongly than elytra. Punctures on tergites 3–6 separated by intervals equal their diameter, punctation sparser on tergites 7–8.

Aedeagus: Median lobe with three dents ventrally ( Figs. 1–6 ).

Female tergite 10 (as seen when pressed by cover glass): Figure 7 .

Variation. In European specimens of Q. cruentus the color of elytra ranges from entirely red through dark brown with lighter sutural and apical margins to completely black. All forms are identical in the structure of genitalia. The only specimen known from North America has dark brown elytra with reddish sutural and apical margins.

Diagnosis. Quedius cruentus may be distinguished from all but one ( Q. fulgidus (Fabricius, 1787)) North American species of Microsaurus by having posterior puncture of sublateral row of pronotum located behind the level of the large lateral puncture. Quedius cruentus differs from Q. fulgidus in having more transverse antennal segments.

Remarks. To include Q. cruentus , the key to species of subgenus Microsaurus proposed by Smetana (1971:49) may be modified as follows:

2(3) Sublateral rows on pronotum with last puncture situated distinctly behind level of large lateral puncture

2a(2b) Antennal segments 7–10 slightly transverse. Elytra brightly red. Aedeagus as in Figure 73 (Smetana 1972). Length 7.0– 11.5 mm ---------------- ---------------------------------------------------------------------------------------------------------------------------- 9. Q. fulgidus (F.)

2b(2a) Antennal segments 7–10 very transverse, about 1.5 times wider than long. Elytra red or dark brown with reddish sutural and apical margins or entirely black. Aedeagus as in Figures 1–6 (this paper). Length 7.0– 10.5 mm ------------------------------------------------------------------- 9a. Q. cruentus (Olivier)

3(2) Sublateral rows on pronotum with last puncture not or about reaching to level of large lateral puncture

Figures

Figs. 1–7. Quedius cruentus (Olivier). 1–6) Ƌ, U.S.A., Black Rock Forest; 7) ♀, Ukraine, Karasevka. 1–4) median lobe of aedeagus, 1—lateral view, 2—ventral view, 3—apex, lateral view, 4—apex, ventral view; 5–6) paramere; 7) female tergite 10. Scales equal 1 mm (1–2, 5), 0.5 mm (3–4, 7), and 0.25 mm (6).