Quadrastichus mendeli Kim and La Salle

Kim, Il-Kwon, Mendel, Zvi, Protasov, Alexey, Blumberg, Daniel & Salle, John La, 2008, Taxonomy, biology, and efficacy of two Australian parasitoids of the eucalyptus gall wasp, Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae: Tetrastichinae), Zootaxa 1910, pp. 1-20 : 6-8

Quadrastichus mendeli Kim and La Salle sp. nov.

( Figs 1 , 4–9 )

Female Length 1.15–1.35 mm. Antenna light brown (or testaceous). Body mainly yellow with dark brown markings; on ocellar triangle, median area of pronotum, latero-posterior corner of pronotum just in front of prothoracic spiracle, apex of axilla, lateral panel of metanotum, median area of propodeum, transverse stripes on gastral tergites 2–4. Legs pale.

Head (Figs 6,7). POL about 2.8 times as long as OOL on shriveled head. Frons with a median area dorsally, bordered laterally by sutures which extend from frontal suture halfway to level of toruli. Vertexal suture very weak and extending from lateral ocellus to eye. Frons with median area but without median carina. The ventral margin of torulus slightly lower than level of ventral margin of eyes. Subantennal groove (hard to see under a microscope due to bright body color) present as a fine line beneath torulus, curved outwardly and extending over half of the distance from torulus to clypeal margin. Gena swollen and malar sulcus distinctly curved. Anterior clypeal margin subtruncate, only with a small lobe slightly protruding.

Antenna ( Fig. 5 ) with three funicular segments and one large anellus. All funicular segments longer than wide and almost equal in length and width; relative length of funicular segments to pedicel as follows: PDL: F1: F2: F3 = 1: 0.7–0.9: 0.7–0.9: 0.7–0.8. Claval segment between C2 and C3 oblique; C3 very short (terminal spine difficult to see due to sensillae on C3). Scape reaching to vertex, but not extending over vertex.

Mesosoma ( Fig. 8 ). Pronotum about 0.3 the length of the mid lobe of mesoscutum in dorsal view. Mid lobe of mesoscutum with distinct median line and with 3–4 adnotaular setae on each side. Scutellum wider than long (L/W = 0.7); submedian lines and sublateral lines present. 2 pairs of setae on scutellum, anterior seta situated slightly behind midlength of scutellum. Mesosternum nearly flat in front of trochantinal lobe; precoxal suture weak and extending about 0.3–0.4 length of mesopleuron. Dorsellum semicircular in shape and about 0.3 the length of scutellum. Propodeum about 0.5 the length of dorsellum and nearly smooth without distinct median carina or paraspiracular carina. Propodeal spiracle partially covered by a raised lobe of callus. Propodeal callus with 2 setae.

Fore wing ( Fig. 4 ). Submarginal vein with 1 seta, situated slightly basal to the middle. Costal cell without setae. Parastigma and stigmal vein without a hyaline break. Postmarginal vein rudimentary. Relative length of wing veins as follows: CC: MV: STV: PMV = 3.1–3.4: 3.3–3.5: 1: 0.1–0.2. Cubital line of setae extending all the way to basal vein, closing speculum. Bare area of speculum extending to about half the length of the MV. Two small bare circular areas present apical to the stigmal vein, from PMV to uncus and from uncus to the apical end of STV.

Gaster ( Fig. 9 ). Slightly longer than the head plus mesosoma. Hypopygium extending about 0.3–0.4 the length of gaster, reaching up to the posterior margin of the third gastral tergite. Cercus with 3 setae, the longest one slightly curved and about 1.3 as long as the others, which are subequal in length. Ovipositor sheath slightly protruding, very short in dorsal view.

Male. Unknown.

Etymology. The species is named for Dr Zvi Mendel, for his dedication to finding sustainable control measures for Leptocybe invasa .

Material examined. Holotype Ψ: Australia, Queensland, Mareeba, 14.x.2005, J. McDonald & H. Nahrung, ex galls on E. camaldulensis x grandis ( ANIC).

Paratypes: Same data as Holotype (1 Ψ ANIC); Quarantine Reared, Bet Dagan, Israel, 20.viii.2007 (originally Australia, from locations given above under parasitoid collection sites) (65 Ψ as follows. 40 Ψ ANIC; 5Ψ each: QMB, BMNH, USNM, CNC, PPRI).

Discussion. This new species fits the definition of the genus provided by Graham (1991): SMV with 1 dorsal seta, antenna with all funicular segments longer than wide and with 1–3 anelli in female and gaster longer than the head plus mesosoma. Although this species doesn’t match well with the keys for European species which was provided by Graham (1991), the species would run to the anysis -group of Q. anysis (Walker) as follows: frons with median area but without median carina, gena (slightly) swollen, malar sulcus (only slightly) curved, malar sulcus without a large subtriangular fovea just beneath eye, clypeal margin truncate. However, the species differs from all other Quadrastichus on the basis of characters as follows: malar sulcus rather strongly curved, C3 very short and claval sutures oblique, subantennal groove distinct and curved outwardly, clypeal margin subtruncate with a small lobe protruding in the middle, and mid lobe of mesoscutum with 3–4 adnotaular setae. Additionally, this new species appears to have a transverse frontal suture extending between the eyes just ventral to the median ocellus, with a longitudinal frontal suture reaching from the transverse suture to the torulus.

Figures

FIGURES 1 – 3. Habitus. 1. Quadrastichus mendeli Ψ; 2. Selitrichodes kryceri “ dark ” specimen Ψ; 3. Selitrichodes kryceri “ light ” specimen Ψ

FIGURES 4 – 9. Quadrastichus mendeli Ψ. 4. Base of fore wing; 5. Antenna; 6. Head, frontal view; 7. Malar sulcus; 8. Mesosoma; 9. Gaster.