Selitrichodes globulus La Salle & Gates

Salle, John La, Arakelian, Gevork, Garrison, Rosser W. & Gates, Michael W., 2009, A new species of invasive gall wasp (Hymenoptera: Eulophidae: Tetrastichinae) on blue gum (Eucalyptus globulus) in California, Zootaxa 2121, pp. 35-43 : 39-42

Selitrichodes globulus La Salle & Gates , sp. nov.

( Figs 7–12 )

Female ( Figs 7–12 ). Length 0.95–1.5 mm. Head generally dark brown to black, with following areas light brown to yellow: bordering eye margin, both anteriorly and posteriorly, extending from just above ventral eye margin to vertex (although weaker on vertex); transverse stripe covering frontal suture; scrobal cavity, and sometimes longitudinal stripe bordering lateral margin of supraclypeal area. These color patterns variable, and may be very difficult to see in darker specimens. In teneral specimens, there can be more extensive lighter coloration, including entire vertex. Antenna with scape dark brown on dorsal margin; light brown to yellow ventrally; flagellum brown. Mesosoma dark brown to black; dorsellum light brown to yellow. Gaster brown. Coxae brown, may be lighter apically; trochanters light brown to yellow; femora dark brown, lighter apically; fore and middle tibiae light brown to yellow; hind tibia dark brown basally, light brown to yellow apically.

Head ( Figs 8–9 ). Ocellar triangle without grooves; sometimes grooves can be seen only on a shrunken specimen. POL about 3 times as long as OOL. Frontal suture transverse, short, not connected medially and curving ventrally, well separated from eye margin, placed ventral to median ocellus, separated from median ocellus by 1.5–2.0 times its diameter. Scrobal area without distinct median carina; with a small transverse cracklike suture present about halfway between frontal suture and torulus. Torulus level with ventral margin of eye. A broad depression (supraclypeal area) below torulus extending to clypeus and with some pilosity. Gena swollen and with malar sulcus somewhat curved near mouth margin. Clypeal margin bidentate.

Antenna ( Fig. 11 ) with 3 funicular segments and 2 anelli; first anellus longer than second and seemingly composed of two fused segments. First and second funicular segments slightly longer than wide, third slightly wider than long to subquadrate: length/width ratio of F1 1.4–1.7; F2 1.25–1.35; F3 0.95–1.0. Relative length of funicular segments to pedicel as follows: PDL: F1: F2: F3 = 1: 0.55–0.8: 0.55–0.8: 0.5–0.7. Clava 1.5–2.0 times longer than wide, wider than funicle, without distinct terminal spine; C3 very short and its end broad, not tapering apically. Scape slightly flattened.

Mesosoma ( Fig. 10 ). Pronotum very short medially in dorsal view. Mid lobe of mesoscutum with very weak median line and with one row of 4–5 adnotaular setae on each side; some setae may form a partial second row. Mesosternum convex just in front of the trochantinal lobes and without precoxal suture. Scutellum with anterior pair of setae located behind middle. Dorsellum rounded posteriorly and slightly overhanging propodeum. Propodeum medially shorter than dorsellum in dorsal view; with median carina. Propodeal spiracle with entire rim exposed and separated from anterior margin of propodeum by less than its longest diameter. Paraspiracular carina absent. Callus with 2–3 setae.

Fore wing ( Fig. 12 ) hyaline, with very faint infumated cloud posterior to venation. Submarginal vein usually with 2 dorsal setae. Costal cell asetose except for a line of ventral setae near apex. Relative length of wing veins to stigmal vein as follows: CC: MV: STV: PMV = 1.0–1.2: 1: 0.25–0.35: 0.1–0.15. PMV one-third to one-half length of stigmal vein. Speculum small and open posteriorly, cubital line of setae not extending to basal line; speculum may have one to a few small setae on underside of wing. Wing disk beyond speculum densely pilose.

Metasoma. Gaster distinctly longer (1.4–1.6 times) than mesosoma. Hypopygium reaching less than half length of gaster. Cercus with 3 longest setae subequal in length and slightly curved. Ovipositor sheath slightly protruding, very short in dorsal view.

Male. Length 0.85 mm. Body color pattern similar with female (although difficult to determine from a single, teneral specimen). Antenna with 3 anelli and only 3 funicular segments; F1 and F2 quadrate to slightly longer than wide; F3 wider than long. Each successive segment increasingly broader. Funicle and clava without compact subbasal whorls of long setae. Ventral plaque less than one-quarter length of scape, situated near apex of scape.

Type material. Holotype Ƥ: USA: California, Monrovia, 12.xi.2008, coll. G. Arakelian, ex galls on Eucalyptus globulus , emerged 20.xi.2008 ( CDFA).

Paratypes. 50Ƥ, 13 Same data as holotype (30Ƥ,13 ANIC; 4Ƥ each: USNM, CDFA, QMB, LACM, BMNH)

Distribution. USA: California. Although this species has not yet been found in Australia, it is certainly Australian in origin.

Etymology. Named for the specific epithet of the host plant with which this wasp is associated.

Figures

FIGURE 7. Selitrichodes globulus Ƥ. Habitus.

FIGURES 8 – 12. Selitrichodes globulus Ƥ. 8, Head, frontal view. 9, Head, lateral view. 10, Mesosoma, dorsal. 11, Antenna. 12, Fore wing.