Astichus silvani, Neser, Ottilie C., 2012

Neser, Ottilie C., 2012, The first record of Astichus Förster (Hymenoptera: Eulophidae: Entiinae), parasitoids of Ciidae (Coleoptera) in bracket fungi, from the Afrotropical Region and the description of four new species from South Africa, Zootaxa 3183, pp. 49-64 : 58-59

Astichus silvani n. sp.

Figs 2 , 6, 11, 12 ; Map 2.

Etymology. silvani (Latin) = belonging to Silvanus, the god of the forests.

Diagnosis. Both sexes: face with white crossband above scrobes only; angle between stigmal and postmarginal veins of forewing 60º and infuscated ( Fig. 6). Female: head with two broad longitudinal bands, thorax with four, as in Fig. 2 ; antenna with scape expanded at apex, reaching median ocellus, funicle segments subquadrate, blackish, with only F3 pale yellow ( Fig. 11 ); forewing hyaline with two wide brown crossbands and one narrow band basally, as in Fig. 6, disc with row of 7 setae below marginal vein on ventral surface; propodeum smooth and shiny with median carina; gaster with posterior margin of T1–3 incised medially, cercus with one long and two slightly shorter setae. Male: scape expanded, F1 without peduncle, F2–4 pedunculate, club without spicule but long, curved setae at apex ( Fig. 12 ).

Description. Female. Length: 1.4–1.6 mm (average 1.5 mm). Colour: Head, thorax and propodeum with various dark bands as follows ( Fig. 2 ): three crossbands on face between inner orbits and scrobes, two lower bands reaching scrobes margin, dorsal band not reaching scrobes, two broad longitudinal bands on vertex and two short bands behind each eye; four dark longitudinal bands on mesoscutum, the lateral bands wide, extending onto side lobes, axillae and scutellum, two centre bands only extending a short way onto scutellum; ventro-laterally a narrow band extending from front margin of pronotum to tegulae; head greenish, mesoscutum turquoise, scutellum and propodeum purple, dorsellum dark; head with yellow line at mouth margin, including the inconspicuous oval clypeus, above clypeus a dark brown crossband with two whitish spots above it at each end; eyes red; scrobes with narrow white band only across apex; antenna ( Fig. 11 ) shiny black except scape with white spot at base and F3 yellowy white; rhinaria and setae on two basal funicle segments dark, pale on following segments and club; forewing ( Fig. 6) hyaline with three brown crossbands, the basal band below parastigma narrow, C-shaped, curving towards wing apex, median band below darkened section near base of marginal vein wider, complete, distal band below postmarginal vein complete; angle between stigmal and postmarginal veins dark, disc setae dark; hind wing hyaline; legs pale brown except coxae, mid and hind femora black, apical tips of all tibiae, basal two-thirds of mid and hind tibiae, tarsal segments two and four dark brown; gaster ( Fig. 2 ) shiny purple-black with blue sheen at base and coppery at apex.

Head. Eyes and face sometimes collapsing slightly; setae short, sculpture finely rugulose, smoother at mouth; head slightly wider than thorax, in dorsal view nearly twice as wide as long, 1.6 times as wide as vertex, in frontal view about one and a half times wider than high, eyes more than one and a half times longer than malar space, delicate malar groove present; eyes with very short pale setae; IOL 5, OOL 4, POL 10; antennae inserted at lower eye level, small oval ridge between toruli, scrobes smooth and shiny, more or less hourglass-shaped, margins rounded, two shiny tubercles at inner orbit between lower and mid dark bands, two small shiny depressions on each side of scrobes, between mid and upper dark bands; antenna ( Fig. 11 ) with scape flattened, expanded apically, as wide as pedicel length at apex, reaching median ocellus, as long as club, pedicel same length as funicle segments, which are longer than wide (6:4), F4 oval, club one-segmented (no discernible septa at high magnification); rhinaria as long as segments but some with short bases, diagonal on F1; setae on funicle short; flagellum longer than head width.

Mesosoma. Sculpture on thorax as on head; pronotum very short and rounded, upper mesepimeron shiny and smooth; mesoscutum as long as scutellum with a few short scattered setae, two longer slender setae near hind margin; notauli deep and complete; scutellum with two pairs of strong setae, the anterior pair longest; axillae sculptured, with two setae facing inward; dorsellum short, sculptured; propodeum smooth and shiny with median carina, about a quarter as long as scutellum, callus smooth and shiny with two setae; forewing ( Fig. 6) with apex rounded, nearly two and a half times as long as wide, three setae on submarginal vein, two on parastigma, faint hairlines in distal part of wing, marginal vein very long, about half wing length, about twice the length of submarginal, row of 7 setae on ventral side of wing below basal half of marginal vein, postmarginal and stigmal veins equal, short, stigmal and postmarginal veins forming angle of more or less 60˚, stigmal knob not expanded, fringe setae half of stigmal vein length.

Metasoma. Gaster ( Fig. 2 ) elongated and pointed, nearly twice length of mesosoma in lateral view, smooth and shiny, with uneven rows of longish setae ventrally on segments, faint sculpture ventrally at base; T1–3 with median incisions on posterior margins, gaster sometimes collapsing in middle, row of setae dorsally on posterior margin of T6; cercus with one long and two slightly shorter setae, epipygium shiny with some setae, bulging upwards; ovipositor somewhat setose, protruding about the length of lateral part of epipygium.

Male. Similar to female but smaller and not as boldly coloured; antenna ( Fig. 12 ) dark, except base of scape and peduncles white, scape not expanded as strongly apically as in female, pedicel narrower than funicle segments, F1 without peduncle, F2–4 with peduncles longer than nodes, very long dark setae in whorls on all funicle segments and three-segmented club, no spicule but long curved setae at apex; wing pattern well developed as in female, except bands slightly narrower.

Remarks. The wing pattern of this species is closest to that of A. townesi Tachikawa , but the female antenna of A. townesi is very different, with all funicle segments white and elongated, F1 sessile and F2–4 pedunculate ( Tachikawa 1983, fig. D), whereas A. silvani has subquadrate funicle segments and only F3 yellow.

Type material. SOUTH AFRICA. Mpumalanga Province: Holotype Ƥ ( HYMC 05749), Mooihoek Farm, nr. Wakkerstroom, 27º13'S 30º32'E, 15.vii.2008, S & OC Neser, with Ceracis cucullatus & Cis sp. E from Stereum ostrea (Stereaceae) (BF144) on fallen tree trunk. Paratypes 24Ƥ 53 same data as holotype; 1Ƥ ( HYMC 05750) same data except with Ceracis cucullatus , Cis spp. E & Q from Trametes sp. ( Polyporaceae ) (BF113); 13 ( HYMC 05748) same data except with Ceracis cucullatus & Cis sp.Q from Coriolus versicolor (Polyporaceae) (BF140); 6Ƥ 43 ( HYMC 05747) same data except from Ganoderma applanatum (Ganodermataceae) (BF139) (2Ƥ 13 QM). Limpopo Province: 1Ƥ ( HYMC 05266) Blouberg, NW of Polokwane, 23º04'S 28º59'E, 27.iv.2007, OC Neser, with Ceracis cucullatus & Cis sp.Q from Trametes sp. ( Polyporaceae ) (BF34); 1Ƥ ( HYMC 05751) Wonderwoud, Wolkberg Wilderness Area, 24º 01'S 30º04'E, 31.viii.2008, S Neser, ex Ciidae from unidentifiable bracket fungus (BF171). North West Province: 3Ƥ 13 ( HYMC 01472) Tonquani Kloof, Magaliesberg, 25º50'S 27º29'E, 13.x.2002, OC Neser, with Cis sp.E from Trametes meyenii (Polyporaceae) (BF22); 13 (HYM 05838) Trident Kloof, Magaliesberg, 25º46'S 27º39'E, 31.vii.2011, S Neser, ex Ciidae from unidentified bracket fungus.

Figures

FIGURES 1 – 4. Dorsal habitus of female. 1. Astichus micans. 2. Astichus silvani. 3. Astichus gracilis. 4. Astichus naiadis. Scale bar = 1 mm.

FIGURES 9 – 16. Male and female antennae. 9. Astichus micans Ƥ. 10. A. micans 3. 11. A. silvani Ƥ. 12. A. silvani 3. 13. A. gracilis Ƥ. 14. A. gracilis 3. 15. A. naiadis Ƥ. 16. A. naiadis 3.