Stenodema holsata (Fabricius, 1787)

Figs 1 D, F, 2 H, 3 D – F, 4 B, D, 5 I – L, S, T, 11 H, I

Cimex holsatus Fabricius, 1787: 306 (original description).

Stenodema holsatum: Reuter 1904: 6 (comb. nov., key to species); Carvalho 1959: 303 (catalogue); Kerzhner and Jaczewski 1964: 958 (key to species); Wagner and Weber 1964: 97 (key to species); Wagner 1974: 114 (key to species).

Stenodema holsata: Kerzhner 1988: 99 (key to species); Muminov 1989: 128 (key to species); Vinokurov and Kanyukova 1995: 99 (key to species); Kerzhner and Josifov 1999: 194 (catalogue). 2

Diagnosis.

Body length in male 4.7–5.7, in female 5.5–6.4; hemelytron often with brown to dark brown stripe along inner margin; frons not protruding above clypeus base (as in Fig. 1 H, I); body length / pronotum width in female 3.9–4.3; antennal segment I in male and female 0.9–1.0 × as long as head width; antennal segment I narrower than forefemur; antennal segment II narrower than hind tibia, 4.0–4.4 × as long as vertex width; setae on antennal segment I shorter than half of antennal segment I width; labium reaching hind coxa, but not surpassing it; hind femur only slightly tapering toward apex, without spines (Fig. 2 H); hind tibia straight basally (as in Fig. 2 J); swelling above propleural suture curved (as in Fig. 1 H); groove on posterior part of mesopleuron absent (as in Fig. 1 M); paired pits on pronotum between calli present, slit-like (Fig. 1 F); setae on posterior margin of hind femur as dense as on other parts of femur, distinctly shorter than hind femur width (Fig. 2 H); hind femur with distinct markings; genital capsule as wide as long, rounded apically and with swelling near apex, without outgrowths near paramere sockets (Fig. 5 U); apical half of right paramere wider than basal part (Fig. 5 M); left paramere with elongate thin apical process and with additional outgrowth apically, with sensory lobe swollen (Fig. 5 N), apical process rounded apically in posterior view (Fig. 5 P); vesica with four membranous lobes (Fig. 3 D – F); dorsal labiate plate wider than long; sclerotized ring 2.5–3 × as wide as long; distance between sclerotized rings ~ 1.5 × longer than sclerotized ring width; membranous swelling at middle of dorsal labiate plate present, triangular (Fig. 4 D); posterior wall with dorsal structure between interramal lobes (Fig. 4 B).

Distribution.

Stenodema holsata has a trans-Palearctic distribution, spanning from southern and western Europe to the Russian Far East, and also known from Central Asia (Kerzhner and Josifov 1999).

Notes.

Stenodema algoviensis and S. holsata are two similar species. Wagner (1974) in the key to Stenodema species separated those two taxa by the antennal segment I length / head width ratio. However, we found that this ratio is only different in males (1.1 in S. algoviensis, 0.9–1.0 in S. holsata), which was also previously found by Tamanini (1982). Additionally, males are different in the antennal segment II / vertex width ratio (5.0 in S. algoviensis, 4.0– 4.4 in S. holsata). In terms of genital structure, these two species differ in the shape of the left paramere i. e., S. holsata has an additional outgrowth near the apical process, whereas in S. algoviensis only a small swelling is present (Wagner 1974: figs 5 N, 90 E, F; Tamanini 1982: fig. 2 A, B, F, G). Vesica and female genitalia of S. algoviensis, as well as molecular data, were not studied.