Aulacus williamsi Jennings & Parslow & Austin 2018, sp. nov.
Creators: name: Jennings, John T.
name: Parslow, Ben A.
name: Austin, Andrew D.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Aulacidae
Aulacus
Aulacus williamsi

description: Aulacus williamsi Jennings & Austin, sp. nov.
Figs 53, 67.
Material examined. Holotype. ♀, " The Blowhole, Boonanghi S.F., W of Kempsey, NSW. 10-12 Dec 1994. G. Williams " "emerged from fallen Backhousia myrtifolia branch ex rainforest" (AMS). Paratypes. NSW: 1♀, Breakneck Lookout, 11 km SSW Taree, 13–24.xi.1991, G & T Williams (AMS); 4♀, 2♂, same data as holotype, various dates (AMS). Queensland: 1♀, Tinana Creek 35m, 25.752’ S 152.694 ’E, 22.xi-7.xii.2011, G Monteith (QM).
Description. FEMALE. Length. 8.0 (7.0–8.5) mm, excluding ovipositor.
Colour. Head and mesosoma black, antenna orange except last two flagellomeres black, small amount of orange on lower gena, clypeus, and anteriorly on propleuron, legs orange except for variable amounts of black basally on coxae, metasomal T1 and T2 largely orange with remaining segments blackish brown, ovipositor sheaths with broad band of orange in apical half, but excluding the tip; ovipositor lighter orange (Figs 53A, B). Wings hyaline except for dark brown spot apically on the marginal and submarginal cells of fore wing (Fig. 53B).
Head. 1.55 (1.50–1.60)× wider than long when viewed dorsally (Fig. 53C); face rugose-reticulate, pubescence long; shallow sub-antennal groove; frons without lateral medial carina above toruli, rugose-reticulate, with long pubescence; vertex rugose-reticulate, almost strigate-reticulate, with scattered short setae (Fig. 53C); gena rugosereticulate, pubescence short; posterior margin of head slightly concave in dorsal view; occipital carina absent; malar space 0.32 (0.30–0.33)× height eye; clypeus 2.8× as wide as high, margin sinuate, with distinct medial process; distance from lateral ocellus to eye margin 0.62 (0.54–0.67)× distance between lateral ocelli; scape 1.7× length pedicel; first flagellomere 1.1× as long as scape, 0.55× as long as second flagellomere.
Mesosoma. Propleuron reticulate, pubescence long, ventro-lateral carina present; pronotum rugose; mesoscutum in lateral view angular antero-dorsally (Fig. 53D), medial and lateral lobes strigate, with scattered short setae, admedial lines present (Fig. 53E); notauli distinct, carinate, narrow and deep; scutellum and axillae strigate, scutellum anteriorly with pair of oblique, deep depressions, separated by median carina (Fig. 53F); metapostnotum scrobiculate, posterior margin slightly curved; mesopleuron rugose, with long pubescence; mesepimeron broad, carinate; metapleuron rugose, with short pubescence; propodeum coarsely rugose, posterior margin weakly rugose; hind coxa strigate dorsally, pubescence long laterally, ovipositor guide about ¾ way along coxae, oblique, distal fringe of long setae, setae in the groove (Figs 53G,H); hind trochanter imbricate, with scattered short setae; prefemur on hind leg present; hind femur imbricate, with scattered short setae; hind tibia imbricate, pubescence short, with scattered stout emergent setae; hind femur 0.80 (0.79–0.82)× length hind tibia; hind tibia with ventro-apical pecten of short robust spines; hind tarsomeres 1–4 with ventro-apical pecten of short robust spines, tarsomere 1, 2.7 (2.6–2.9)× length tarsomere 2; tarsomere 2, 1.6 (1.4–1.7)× length tarsomere 3; tarsomere 3, 2.6 (2.5–2.8)× length tarsomere 4; tarsomere 4, 0.50 (0.45–0.55)× length tarsomere 5; hind tarsal claw 0.56 (0.55–0.58)× length tarsomere 5; fore wing veins 2r-m and 3r-m largely spectral; hind wing venation complete, R+Rs, M+Cu, Cu, r-m and 2-M spectral, with 3 hamuli.
Metasoma. Ovate, about equal to length of mesosoma (Fig. 53B); T1 and T2 broad, glabrous, with several very shallow small punctures anteriorly; ovipositor 5.3 (5.0–5.7) mm.
MALE. Similar to female except: flagellomeres brown, becoming progressively darker towards tip; length 9.0 (8.5–9.6) mm; metasoma 1.47 (1.33–1.61)× length mesosoma; digitus slightly longer than basiparameres; basiparameres broad, glabrous basally to reticulate and with long setae apically.
Etymology. This new species is named after the collector, Geoff Williams OAM, research associate with the Australian Museum, Sydney NSW.
Distribution. This species is known from Taree and Kempsey, NSW and Tinana Creek, Queensland (Fig. 67).
Biology. This species has been reared from the dead or fallen branches of Backhousia myrtifolia (Myrtaceae) in dry rainforest, Boonanghi State Forest, NSW and one female from B. sciadophora in dry rainforest near Taree, NSW. The insect host is unknown.
Comments. Aulacus williamsi keys out with A. nebo. Both species have the mesosoma angular in lateral view, metasoma ovate, fore wing with apical spot at apex, hind wing venation complete, and a distal, oblique ovipositor guide on the hind coxa. They can be readily distinguished by colouration— A. nebo has an orange-brown head, meso- and metasoma, whereas the head and mesosoma are black and metasomal T1 and T2 are largely orange with remaining segments blackish brown in A. williamsi.
The male of A. williamsi is slightly longer and has a narrower and more elongate metasoma than the female. The flagellomeres also differ in colour, being brown, becoming progressively darker towards the tip.
description: Published as part of Jennings, John T., Parslow, Ben A. & Austin, Andrew D., 2018, Systematics of the parasitoid wasp genus Aulacus Jurine (Hymenoptera: Evanioidea: Aulacidae) from Australia, pp. 1-113 in Zootaxa 4538 (1) on pages 94-96, DOI: 10.11646/zootaxa.4538.1.1, http://zenodo.org/record/3771367