Gonatocerus (Lymaenon) mitjaevi Triapitsyn & Rakitov

Rakitov, Roman & Triapitsyn, Serguei V., 2013, Egg parasitoids (Hymenoptera: Mymaridae and Trichogrammatidae) of the gall-making leafhopper Scenergates viridis (Hemiptera: Cicadellidae) from Uzbekistan, with taxonomic notes on the Palaearctic species of Aphelinoidea, Zootaxa 3683 (5), pp. 538-548 : 545-547

Gonatocerus (Lymaenon) mitjaevi Triapitsyn & Rakitov , sp. n.

( Figs. 25–33 )

Gonatocerus sp.: Rakitov & Appel 2012: 12 –13, 16, 18 (host association, natural history information, illustrations).

Type material. Holotype female [ UCRC] on slide: 1. “ UZBEKISTAN, Bukhara Province, Kagan District, Ecocenter “Dzheyran”, 39°34’27’’N 64°42’57’’E, 227 m, 4-16.viii.2011, R. Rakitov, from eggs of Scenergates viridis (Vilbaste) on Alhagi maurorum ”; 2. “Mounted at UCR/ERM by V. V. Berezovskiy 2011 in Canada balsam”; 3. [red] “ Gonatocerus (Lymaenon) mitjaevi S. Triapitsyn & Rakitov HOLOTYPE Ƥ”; 4. “Det. by S. V. Triapitsyn 2011”; 5. [ UCRC database label] “Univ. Calif. Riverside Ent. Res. Museum UCRC ENT 315236”.

Paratypes: same data as holotype [4 Ƥ, 2 3 on slides, UCRC, and 31 Ƥ, 19 3 on points, CNCI (2 Ƥ, 1 3), ICXU (1 Ƥ, 1 3), UCRC (23 Ƥ, 12 3), USNM (1 Ƥ, 1 3), ZIN (2 Ƥ, 2 3), ZMUM (2 Ƥ, 2 3)].

Additional (non-type) material examined. Same data as holotype [5 Ƥ, 2 3 in ethanol, UCRC].

Description. FEMALE (holotype and paratypes). Body length 860–1120 (dry-mounted specimens). Face yellow to light brown; gena, vertex, and occiput mostly brown; scape and pedicel mostly yellowish with some light brown, flagellum brown. Pronotum light brown or yellowish, rest of mesosoma dark brown with edges of midlobe of mesoscutum and scutellum contrastingly yellow or light brown (however, such color pattern in the subgenus G. ( Lymaenon ) often is caused by preserving freshly emerged individuals); legs yellowish to brown. Gaster mostly yellow with apical terga brownish.

Antenna ( Fig. 25 ) with radicle 0.34–0.37× total length of scape, rest of scape 2.7–3.2× as long as wide, faintly longitudinally striate; pedicel longer than F1; F2 a little shorter than F1 or F3, F4 a little longer than preceding funicle segments, F5 the longest funicle segment, F6 a little shorter than F5 or following two funicle segments; mps on F5 (usually 1, occasionally 2), F7 (2 or 3), and F8 (2 or 3); clava with at least 14 mps, 3.3–4.1× as long as wide, about as long as or a little longer than combined length of F6–F8.

Mesosoma ( Fig. 26 ). Mesoscutum and scutellum with very weak, inconspicuous sculpture. Fore wing ( Fig. 27 ) 2.8–3.0× as long as wide; longest marginal seta 0.22–0.29× maximum wing width; disc hyaline, bare behind submarginal vein, with setae sparse between marginal vein and cubital row of setae, sometimes leaving a very small bare area, and densely setose elsewhere (discal setae rather short). Hind wing ( Fig. 27 ) 19–21× as long as wide; disc hyaline and unevenly setose; longest marginal seta 2.4–2.9× maximum wing width.

Metasoma ( Fig. 26 ). Gaster much longer than mesosoma. Petiole 2.1–3.4× as wide as long. Ovipositor occupies 0.8–0.9 length of gaster, posteriorly exserted beyond its apex by 0.11–0.12 own length, and 2.4–2.5× length of mesotibia.

Holotype measurements. Body: 1137 [length of dry-mounted specimen prior to slide-mounting 930]; head: 185; mesosoma 320; petiole 15; gaster 677; ovipositor 650. Antenna: radicle 70; rest of scape 121; pedicel 55; F1 27; F2 25; F3 31; F4 36; F5 53; F6 41; F7 49; F8 51; clava 172. Fore wing 781:281; longest marginal seta 73. Hind wing 646:34; longest marginal seta 82.

MALE (paratypes). Body length 860–1030 (dry-mounted specimens). Similar to female except the following. Face yellow with some light brown; gena and vertex yellow to light brown or brown; scape and pedicel mostly yellowish, flagellum brownish; pronotum mostly yellow, rest of mesosoma dark brown with edges of midlobe of mesoscutum and scutellum yellow ( Fig. 28 ); legs mostly yellowish-brown (tarsi slightly darker). Antenna ( Fig. 29 ) with scape plus radicle about 2.7× as long as wide. Wings ( Fig. 30 ) hyaline; fore wing 2.7–2.8× as long as wide. Genitalia as in Fig. 31 .

Diagnosis. In Triapitsyn (2013), G. (Lymaenon) mitjaevi would key to couplet 14 together with G. (Lymaenon) kulik Triapitsyn , from which it differs by the much lighter color of the gaster and also by the absence of mps on F6 and the presence of at least 14 mps on the clava of the female antenna (1 or 2 mps on F6, and usually 9, at most 11, mps on the clava of G. kulik ). The combination of characters displayed by this species is unique among the Palaearctic species of G. ( Lymaenon ).

Etymology. The species is dedicated to Ivan Mitjaev, who first described the gall-inducing habit of the leafhopper host of this parasitoid ( Mitjaev 1968).

Host. Scenergates viridis (Vilbaste) ( Hemiptera : Cicadellidae ) ( Rakitov & Appel 2012 [as Gonatocerus sp.]).

Biology. Females were observed in the daytime searching on the surface of S. viridis galls. They oviposit through the gall’s outer epidermis (corresponding to the abaxial surface of the camelthorn leaf). Emerging wasps chew exit holes through the same epidermis ( Figs. 32, 33 ). Therefore, unlike A. sariq , this larger species does not penetrate the gall chambers, which explains why no adults were found trapped in the “plugs”. The S. viridis eggs parasitized by G. mitjaevi are readily seen from the gall’s inner side because of the bright-orange material deposited posteriorly of the developing parasitoid ( Fig. 32 , inset).

Figures

FIGURES 25 – 33. Gonatocerus mitjaevi. 25 – 27. Female (holotype): 25. Antenna. 26. Body. 27. Wings. 28. Male, live specimen. 29 – 31. Male (paratype): 29. Antenna. 30. Wings. 31. Genitalia. 32. Exit holes on the outer surface of a Scenergates viridis gall. Inset: the gall’s inner surface with tips of S. viridis eggs visible, the one with the orange tip is parasitized with G. mitjaevi and the two others, with Aphelinoidea sariq. 33. Head of an emerging adult male showing from the exit hole, scanning electron micrograph.