Igutettix pulverosus Matsumura, 1932

Ohara, Naomichi & Hayashi, Masami, 2022, Recognition of the genera Igutettix Matsumura and Vilbasteana Anufriev (Hemiptera: Cicadellidae: Typhlocybinae), with discovery of a new related genus from Japan, Zootaxa 5125 (1), pp. 63-74 : 64-68

Igutettix pulverosus Matsumura, 1932 sp. rev.

( Figs. 1–2 , 9 , 13, 14 , 19–23 , 31–34 )

Igutettix pulverosus Matsumura, 1932 , Ins. Mats., 6: 105 [Honshu: Harima].

Igutettix oculatus: Dworakowska 1993 (partim), Entomol. Abhandl. Staatl. Mus. Tierk. Dresden, 55: 99 (nec Lindberg, 1929).

Body stramineous to dark orange. Head with pair of oblong black markings centrally, black, and pair of small triangular fuscous markings posteriorly; face fuscous in ventral half, with 2 pairs of markings dorsally, upper pair oblong (occasionally obscure) and lower one rounded, brown to fuscous. Pronotum bearing 2 pairs of fuscous spots laterally, pair of obscure markings pale brown centrally; mesonotum with basal triangles fuscous and scutellar suture brown. Fore wing semitransparent, pale brown in apical ⅓, with veins yellowish. Abdomen brown to fuscous.

Head 0.9 times as wide as pronotum; vertex 1.6–2.0 times as wide as dorsal midline, 1.5–1.9 times as long as next to eye, 0.4 times as long as pronotum; anteclypeus broad and swollen in male, narrower and relatively flattened in female. Pronotum 1.5 times as wide as long, 1.6–1.9 times as long as mesonotum. Front femur with seta AM1 stout, situated near ventral margin; intercalary row composed of one large stout basal seta and about 10 setae in apical half. Hind femur with macrosetal formula 2+1+1; tibia with setal row AV composed of 6 preapical macrosetae. Male abdominal sternal apodemes very long and nearly paralleled, reaching posterior margin of 6 th sternite. Female 7 th abdominal sternite almost as long as wide, trapezoidal, triangularly expanded caudad, with lateral margin sinuate, with posterior margin emarginate and notched near middle.

Body length (mean): ♂ 3.7–4.1 mm (3.8 mm); ♀ 4.0– 4.5 mm (4.3 mm).

Male genitalia. Pygofer dorsal process large, hook-shaped, sharply curved ventrally and bearing pointed apex; ventro-caudal margin of pygofer strongly produced and digitiform, bearing numerous ridged setae posteriorly. Subgenital plate elongate and triangular, with apex obtuse, bearing 6–8 macrosetae along outer margin of basal half and smaller setae scattered apically. Connective with stem produced dorsally, ‘eboshi’-like, slightly longer than arm. Aedeagus with preatrium about half times as long as shaft; shaft bent dorsally at basal ⅓, rounded apically, bearing ventral process near middle; ventral process extending nearly straight and curved dorsad in apical ⅓, with pointed tip.

Female genitalia. First valvula of ovipositor with dorsal margin expanded subapically and tapering, with dorsal sculpture squamate in apical ⅓, and strigate sculpture arranged into narrow apical and ventral areas. Second valvulae asymmetrical; right valvula with 20–23 small teeth dorsally; left one slightly serrated dorsally. Third valvula slender with ventral margin strongly narrowed subapically.

Distribution. Japan (Honshu, Kyushu).

Material examined. Holotype: ♀ (abdomen lost), “Type Matsumura, Iguchi 7/27”, “69, 42”, “ Iguchitettix pulverosus M. (handwriting), det. Matsumura ”, “Type Matsumura” (red printed label), “ Zyginoides (handwriting)”, “ Igutettix pulverosus Matsumura , Type”, “11” ( SEHU). [Honshu] 1♀, Yabitsu Pass (760 m), Tanzawa Mts., Hadano , Kanagawa Pref., 20. VIII. 2018, M. Hayashi leg. ( ELKU); 1♂ 1♀, Mt. Matsutake-yama (370 m), Toya, Midori-ku, Sagamihara, Kanagawa Pref., 18. VI. 2019, M. Hayashi & J. Souma leg. ( ELKU); 16♂ 13♀, Hirano (1,050 m), Yamanakako, Yamanashi Pref., 31. VII. 2019, M. Hayashi leg. ( ELKU); 15♂ 22♀, same data except 9. VIII. 2019; 5♂ 2♀, same data except 18. VIII. 2020; 10♂ 6♀, Hirano-Ishiwari (1,050 m), Yamanakako , 18. VIII. 2020, M. Hayashi leg. ( ELKU); 3♀, Hiruzen-shimotokuyama , Maniwa , Okayama Pref., 20. IX. 2008, N. Ohara & K. Kogure leg. ( ELKU); 11♂ 37♀, Lake Nichinan , Nichinan , Tottori Pref., 8. VIII. 2006, M. Ozaki leg. ( ELKU); 13♂ 78♀, same data except 9. VIII. 2006; 3♂ 3♀, Mt. Kakezu-yama , Kitahiroshima , Hiroshima Pref., 6. VIII. 2009, N. Ohara leg. ( ELKU); 13♂ 42♀, Futagô , Kitahiroshima , Hiroshima Pref., 6. VIII. 2009, N. Ohara leg. ( ELKU). [Kyushu] 62♂ 35♀, Mt. Abura-yama , Fukuoka, Fukuoka Pref., 12. VII. 2008, S. Okudera leg. ( ELKU).

Remarks. This species is peculiar in the morphological characters of males, such as abdominal apodemes reaching posterior margin of 6 th sternite, dorsal pygofer process extremely developed, aedeagal shaft smooth and not expanded apically. Adults and nymphs feed exclusively on Japanese dogwood, Cornus kousa of Cornaceae , that inhabits the peripheries of temperate deciduous forests, and adults become abundant during early July to late August.

Figures

FIGURES 1–8. Habitus in dorsal and lateral views. — 1, 2, Igutettix pulverosus Matsumura sp. rev. (♂ 3.7 mm); 3, 4, Vilbasteana oculata (Lindberg) comb. rev. (♂ 4.5 mm); 5–8, Cornicola mizuki gen. et sp. nov. (5, 6, ♂ 4.2 mm; 7, 8, ♀ 4.7 mm).

FIGURES 9–12. Face in males (9–11) and female (12). — 9, Igutettix pulverosus Matsumura sp. rev.; 10, Vilbasteana oculata (Lindberg) comb. rev.; 11, 12, Cornicola mizuki gen. et sp. nov.

FIGURES 13–18. Fore and hind wings in males. — 13, 14, Igutettix pulverosus Matsumura sp. rev.; 15, 16, Vilbasteana oculata (Lindberg) comb. rev.; 17, 18, Cornicola mizuki gen. et sp. nov. Scale: 1.0 mm.

FIGURES 19–23. Male abdominal sternal apodemes (19) and ♂ genitalia (20–23) of Igutettix pulverosus Matsumura sp. rev. — 20, Genital capsule in lateral view; 21, subgenital plate in ventral view; 22, 23, style, connective and aedeagus in lateral (22) and dorsal (23) views. Scales: 0.3 mm (21–23), 0.4 mm (19, 20).

FIGURES 31–42. Female 7th abdominal sternite and apex of ovipositor (1st, 2nd and 3rd valvulae) of Igutettix pulverosus Matsumura sp. rev. (31–34), Vilbasteana oculata (Lindberg) comb. rev. (35–38) and Cornicola mizuki gen. et sp. nov. (39–42). — 31, 35, 39, Abdominal sternite in ventral view; 32, 36, 40, 1st valvula of right side in lateral view; 33, 37, 41, 2nd valvulae of right side in lateral view; 34, 38, 42, 3rd valvula of right side in lateral view. Scales: 0.3 mm.