Ommatidiotus dissimilis (Fallén, 1806)

(Figs 2A–E)

Issus dissimilis Fallén, 1806: 123 .

Ommatidiotus dissimilis Spinola, 1839, 367; Dlabola, 1987: 73.

Ommatidiotus falléni Stål, 1863: 251; Metcalf, 1958: 101 (synonymized by Dlabola, 1987: 74).

Diagnostic characters. Recognized by female coryphe a little produced, the anterior part between the eyes 1/3 shorter, anteriorly very obtusely angulated; in front a little shorter than its width, truncated anteriorly and obtusely angled on both sides, seen from the side it is sufficiently convex and forming a right angle with the apex. (Figs 2A–E) (Fallén, 1806).

Redescription. Female. COLORATION: General coloration of body light yellow. Ventral parts of body darker, distinctly contrast with background. Coryphe concolorous with background with indistinct relatively broad longitudinal dark stripes with a narrow reddish stripe medially, contrasted bicolored, surpassing pronotum and reaching posterior margins of mesonotum. Compound eyes darker than background. Pronotum with reddish median stripe. Paranotal lobes darker than background. Forewings with yellowish stripes weakly developed between cubital and median cells, almost reaching posterior margins. Femur concolorous with abdomen, apices light brown. Tibiae and tarsus concolorous with background. Apices of leg spines black (Figs 2A–E). SURFACE AND VESTITURE: Head, body and forewings with sparse setae, rough. STRUCTURE: Head. Coryphe blunt, length as wide as width at midline, without carinae; anterior margin round, posterior margin weakly concave (Fig. 2C). Metope short and blunt in lateral view, lateral keels converging narrower to apical, sublateral carinae visible (Figs 2D–E). Thorax. Pronotum distinctly shorter than coryphe at midline, without median carinae. Paradiscal fields of pronotum narrower behind eyes. Paranotal lobes of pronotum ovate, protruding ventrally (Fig. 2D). Posterior margin of pronotum concave. Mesonotum large, almost three times longer than pronotum, anterior margin convex, with visible lateral carinae reaching posterior margins (Fig. 2C). Forewings not elongated, abdominal margins almost reaching forewing (Fig. 2A–B). Abdomen. in lateral view, almost flat; length of each tergites almost similar (Figs 2A–B). See Fallén (1806) for original description and Dlabola (1987) also.

Measurements (in mm). Female (n=1). Body length (including forewing): 4.54; body length (excluding forewing): 4.18; body width (including forewing): 1.80; head length: 0.87; head width (including eyes): 1.25; coryphe length: 0.60; coryphe width: 0.69; metope length: 0.86; metope width: 0.80; pronotum length: 0.34; pronotum width: 0.92; mesonotum length: 0.71; mesonotum width: 0.99; forewing length: 3.47.

Material examined. 1♀, Jangbaek-san (Mt.), Joseon;?.1914, Yoichiro Ikuma leg. (SEHU) .

Distributions. North Korea (Mt. Baekdu) *, Transpalearctic.

Hosts. Eriophorum vaginatum ( Poales, Cyperaceae) (Nickel, 2003), Juncus sp. ( Juncaceae) (Lodos & Kalkandelen, 1981).

Remarks. The length and shape of coryphe of this species seems to be influenced by geographic variations (Dlabola, 1987: 77, Abb. 10–17). This specimen was collected in Mt. Baekdu (=Mt. Jangbaek) which is located in the northernmost region of the Korean Peninsula, and has similarities to the Mongolian variations.