Re-description and first host and biology records of Entedon magnificus (Girault & Dodd) (Hymenoptera, Eulophidae), a natural enemy of Gonipterus weevils (Coleoptera, Curculionidae), a pest of Eucalyptus trees Author Gumovsky, Alex Author Little, Dave De Author Rothmann, Sergio Author Jaques, Lorena Author Mayorga, Sandra Elizabeth Ide text Zootaxa 2015 3957 5 577 584 journal article 10.11646/zootaxa.3957.5.6 28d350cc-0799-4850-88ed-462a2ec4273e 1175-5326 237071 50B6EE61-31D1-4B24-8912-B76192319754 Entedon magnificus ( Girault & Dodd, 1913 ) ( Figs 1–3 ) Entedonella magnifica Girault & Dodd , in Girault, 1913 : 154 . Syn. by Bouček, 1988 : 714 . Metacrias clara Girault, 1929 : 324 . Syn. by Bouček, 1988 : 714 . Diagnosis. Body robust, metallic green-bronze ( Fig. 1 ); head in dorsal view wide, about 2.7× as broad as long ( Fig. 1 D), in frontal view frons without frontal sulcus and anterior margin of clypeus somewhat produced ( Fig. 2 B); fore wing just slightly shorter than combined length of mesosoma, metasoma and head ( Fig. 2 A); female gaster ovate, attached by a short petiole to mesosoma ( Figs 1 A, 2A); propodeum with channel on either side of median carina, laterally with complete, wide, antero-lateral sulcus, and smooth near flat submedian areas ( Fig. 2 C). Male ( Figs 1 C, D) with 4-segmented antennal funicle and 1-segmented clava; its fore wing with parastigma somewhat expanded ( Fig. 3 C); legs pale except coxae and metafemur which broadly dark metallic in mid part ( Fig. 1 C); and gaster without pale subbasal spot. Description. Female. Length 1.7–1.9 mm . Body metallic green-bronze; legs pale, except for metallic coxae and brownish pretarsi; antennae dark with metallic tint, except for pale scape; wings transparent, venation pale brown ( Figs 1 A, B, 3C, D); OMA dark, traced mainly by sculpture. Head in dorsal view ( Figs 2 E, F) evenly reticulate, about 2.7× as broad as long; in frontal view ( Fig. 2 B) 1.4× as broad as high. Ocelli relatively large in size; POL nearly 2× OOL. Occipital margin marked off by a sharp carina, notably raised along its main width ( Fig. 2 F). MDO:OOL:OCL in ratio 12:16:11. Eye and occiput moderately pubescent; eye about 2.3× as long as malar space; interocular distance 1.3–1.4× longer than eye height. Frons without frontal sulcus, surface between scrobal depressions weakly raised, without projection. Breadth of mouth cavity ( Fig. 2 D) about 2.3–2.5× malar space. Gena very weakly convex, with faint sculpture. Clypeus not delimited by sutures, its surface with somewhat finer reticulation than rest of face, anterior margin somewhat produced and subrectangular in shape, with four protruding setae ( Fig. 2 D). Mandibles bidentate, with outer tooth notably longer than inner tooth; cutting margin of the teeth smooth ( Fig. 2 D). Antennal torulus situated somewhat above lower eye margin ( Fig. 2 B); antenna ( Figs 2 B, 3A) with scape cylindrical, about 3.6× as long as broad in the middle, nearly (about 0.7×) as long as eye height; combined length of pedicel and flagellum about 0.7× as long as breadth of head ( Fig. 2 E); pedicel about 1.6× as long as broad, about 0.8× as long as F1 ( Fig. 3 A); F1–F3 subcircular, short ovate; clava two-segmented, about 1.8× as long as broad ( Fig. 3 A ) . FIGURE 1. Entedon magnificus . A, B. Female, habitus: A, dorsal view; B, lateral view. C, D. Male, habitus: C, lateral view; D, dorsal view. Mesosoma 1.4× as long as broad ( Figs 1 A, 2A). Pronotal collar weakly carinate ( Fig. 2 E). Mesoscutum slightly more than 2× broader than long, scutellum slightly longer than broad and about 1.5× longer than mesoscutum. Axilla with one seta. Axillula present as a scale-like short projection. Dorsellum narrow, as semicircular, coriaceous area ( Fig. 2 C). Propodeum ( Fig. 2 C) with complete median carina continued to narrow nucha delimited by cristae, and with shallow, smooth longitudinal channel on either side; laterally with antero-lateral propodeal sulcus that continues around spiracular elevation and further along relatively flat submedian areas ventrally to supracoxal flange; each spiracular elevation with a short sharp projection ventral to spiracle; supracoxal flange relatively wide and flat; callus with 1 large and about 15 smaller setae. Fore wing ( Fig. 3 C) just slightly shorter than combined length of mesosoma, metasoma and head ( Fig. 2 A), slightly more than 2× as long as broad; costal cell about as long as marginal vein, about 6.4× as long as broad, bare; subcosta of submarginal vein with 2 dorsal setae; postmarginal vein about as long or somewhat shorter than knob-like stigmal vein; speculum open below; fringe of apical margin about as 1/2–2/3 as long as breadth of parastigma in its widest part; marginal vein narrowly but notably widened in place of transition into parastigma ( Fig. 3 C). Metacoxa with dense pubescence of about 15 bristles on dorsal surface ( Fig. 2 C). Metasoma with petiole notably wider than broad, with distinct collar ( Fig. 2 C); gaster about as long as broad ( Figs 1 A, 2A). FIGURE 2. Entedon magnificus , female, SEM. A, habitus, dorsal view; B, head, frontal view; C, propodeum; D, lower face; E, head and anterior mesosoma; F, occiput. FIGURE 3. Entedon magnificus , antenna (A, B) and fore wing (C, D). A, C: female. B, D: male. Male ( Figs 1 C, D, 3B, D). Similar to female, except as follows. Antennal scape with darkened extreme tip ( Fig. 1 C, 3B ) , metafemur with broad dark green metallic region ( Fig. 1 C ) covering major part of dorsal and lateral surfaces (wholly pale in female). Antenna ( Fig. 3 B ) with five separate segments (clava 1-segmented); antennal scape notably wide, about 2.7 × as long as broad; pedicel slightly longer than broad; funicular segments notably longer than in female: F1 2.6 × as long as broad, slightly longer than F2, and F2, F3, F4 and clava (without long terminal spine) slightly longer than broad ( Fig. 3 B). Fore wing ( Fig. 3 D) with marginal vein 3 × wider in place of transition into parastigma than in place of transition to postmarginal vein. Metasomal petiole cylindrical, 1.8 × longer than broad. Material examined. 3♀, Australia , Tasmania, Hobart, Runnymede, ex Gonipterus platensis , coll. beginning December 2011 , emerged 20 December 2011 (D. de Little) ( SIZK ); 4♀, 1♂ , Australia , Kinglake, N.Prk., nr. Melbourne, VICT ., 31.i.77 (Zd. Bouček) [identified by Zd. Bouček] ( BMNH ); 7♀, 17♂ , Australia , Tasmania, Hobart Area, 42.54S 147.18E , xii.1987 , ex larva of Gonipterus scutellatus on eucalypt (G. Tribe) ( PPRI ). Host. Weevils of the genus Gonipterus Schoenherr ( Coleoptera : Curculionidae ) (e.g. G . platensis , G . scutellatus Gyllenhal ) on Eucalyptus trees. Biology. Koinobiont, gregarious larval endoparasitoid; this is also the first regional host and biology record for indigenous Australian species of the genus. Distribution. Australasian region: continental Australia and Tasmania. Remarks. The only available descriptions are the brief ones of Girault (1913 , 1915 ). The species was described in two different genera ( Entedonella and Metacrias ), both synonymized afterwards by Bouček (1988: 713) under Entedon . These descriptions are based on females only, are rather brief, and do not provide any dimensions. Therefore, we provided a re-description of this species based on recent examination of specimens of both sexes. Entedon magnificus is a rather distinctive species possessing wide head, bright copper coloration and predominantly pale legs and antennal scape, and short antennal segments in both sexes. No other species (described and undescribed) from Australasia studied by the first author has such combination of characters. The male has an expanded parastigma and darkened metafemora. The expanded parastigma is somewhat similar to the Palearctic E. costalis Dalman , however, it is much more evidently expanded in that species (the male of which also differs in having the fore wing densely setose basally, the clypeus with distincly produced anterior margin, and darkened legs and antennae). The darkened (bearing a dark metallic spot) metafemora of the males of E. magnificus are rather unique among species of Entedon . Generally, males of Entedon have paler coloration than females, but sexual dimorphism is opposite in E. magnificus— females have entirely pale femora, whereas males have darkened metafemora. Entedon magnificus might be confused with the Palaearctic E. pallicrus Erdős , which also has broadly pale tibiae and a bright metallic mesosoma. However, the latter species notably differs by the shorter head of both sexes (2.3× as broad as long in dorsal view, 2.7× in E. magnificus ) and wider mouth cavity (5.0× as broad as length of malar space; 2.3–2.5× in E. magnificus ). Also, both sexes of E. pallicrus possess a reduced antero-lateral propodeal sulcus, whereas in E. magnificus the sulcus is complete and extends around the spiracular elevation and further along to the supracoxal flange ( Fig. 2 C). Ecology. The host weevil, Gonipterus platensis ( Figs 4A , B ). Adults and larvae of this species feed on new developing Eucalyptus leaves, buds and shoots, mainly on E. globulus . A female lays around 800 eggs in groups of 4–16 laid on developing shoots and leaves, and the mass is protected by a capsule made of faeces ( Loch 2008 ). Both males and females can live for more than one year. In laboratory conditions (20–23 °C) the larvae emerge after 7–10 days, chewing the base of the egg mass and through the leaf; there are four instars over 4–6 weeks ( Araya & Guerrero 2002 ; Santolamazza-Carbone et al. 2006 ). When the larva is fully grown, it stops eating and falls to the ground where it buries itself. The larva then makes a pupal chamber, with this stage taking almost 45–60 days ( Freitas 1991 ; Sanches 1993 ). FIGURE 4. A and B, Gonipterus platensis weevils, habitus. C and D, female of Entedon magnificus ovipositing into Gonipterus platensis larva feeding on Eucalyptus leaf. FIGURE 5. Entedon magnificus , final instars. A, body of completely eaten Gonipterus larva filled with final instars of E. magnificus ; B–E, parasitoid larvae emerging from remnants of its host, mature larva of Gonipterus sp.; F and G, pupae. The parasitoid, Entedon magnificus . The available data suggest that E. magnificus is a gregarious endoparasitoid of larvae of Gonipterus weevils. The females oviposit directly into larvae of the host weevil ( Figs 4 C, D); 15– 30 larvae develop within the same host ( Figs 5 A–E). When a parasitized mature weevil larva approaches its maximum size, the parasitoid larvae start destructive feeding. They eventually consume the entire host body and stay covered by the host skin ( Fig. 5 A). Soon after the host skin breaks, revealing numerous mature parasitoid larvae ( Figs 5 B–E). The emerged larvae are pale-yellow in color with darker contents in the mid gut (filled with the meconium). Soon afterwards the larvae void the meconium, turning into the prepupae and then pupate nearby ( Fig. 5 F). The pupae stay attached to a substrate by shriveled larval skins ( Fig. 5 G).