Gobryidae McAlpine 1997
Creators: name: Lonsdale, Owen
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Gobryidae

description: Gobryidae McAlpine, 1997
(Figs 67–70, 82–97, 402)
Type genus: Gobrya Walker 1860: 166, by McAlpine (1997a: 182). Type species of genus: Gobrya bacchoides Walker, 1860: 167, by monotypy.
The family Gobryidae is one of the most recently described families of flies. They were termed “hinge flies” by McAlpine (1997b) because of the characteristic articulation of the narrow, straight abdomen with the thorax, which is also seen to a lesser degree in the Megamerinidae, the family in which there were once placed. Gobryidae consists of at least eight species in the single genus Gobrya (McAlpine, 1997b), although only five are described. Species occur in the Oriental Region and adjoining parts of the Australian Region. There is no key to species. Species were catalogued as Megamerinidae in Steyskal (1977e) [Oriental] and Evenhuis (1989b) [Australian].
Biology. The biology of Gobrya is unknown, although specimens have been collected on foliage or near the margin of lowland rainforests (D.K. McAlpine, 1997b).
Immature stages. Unknown.
Adult Diagnosis. Colour dark brown (including halter knob), slightly iridescent, with antenna, mouthparts and parts of legs white to yellow; body surface mostly glossy (Figs 82–88). Body length 3.5–8.0mm. Antenna elbowed, first flagellomere elongate; pedicel with dorsal suture; arista sparsely long plumose, with rays becoming shorter apically and sparser ventrally to base. Head short and broad, nearly twice width of thorax; face convex and well sclerotized with mouthparts ventral and receded; frons and dorsum of ptilinal suture narrow (lateral arms nearly absent). Cephalic chaetotaxy reduced to two verticals, with vibrissa, fronto-orbitals, postocellar and ocellar setae absent. Thoracic chaetotaxy reduced to notopleural (one), two supra-alars, and apical scutellar (on slight tubercle). Broad precoxal and postmetacoxal bridges present, although postmetacoxal bridge sometimes membranous medially. Hind femur long and stout with two ventral rows of spines. Abdomen petiolate, straight and narrow with apex slightly widened. Wing with anal lobe and alula strongly reduced; costa unbroken; subcosta complete; R 4+5 and M 1 slightly convergent (Fig. 402). Male external terminalia globular and asymmetrical (Figs 89–97).
Adult Definition. Colour dark brown (including halter knob and sometimes base), slightly bluish iridescent on darkly pigmented sections, and with antenna, mouthparts and parts of legs white to yellow (Figs 82–88). Body length 3.5–8.0mm.
Chaetotaxy: 1 inner vertical; 1 outer vertical; 0 fronto-orbital; 0 ocellar; 0 postocellar; vibrissa absent. Face and gena irregularly and sparsely setulose. Postoccipital setae present dorsolaterally. 0 presutural intra-alar; 0 postpronotal; 0–1 anterior notopleural, 1 posterior notopleural; 0–1 posterior supra-alar; 0 posterior intra-alar; 0 dorsocentrals; 0 acrostichals; 1 apical scutellar (on small tubercle); 0 proepisternal; 0 anepisternal; 0 katepisternal (sometimes with dense setulae ventrally). Body mostly glossy and bare with very short microtomentum present on head, notum, limited portions of abdomen, and pre- and postmetacoxal bridges; setulose on prosternum (posteriorly and laterally), posterior margin of anepisternum, behind posterior thoracic spiracle, katepisternum, notum and gena; parafacial and lateral margin of frons with single row of erect setulae; pedicel with several ventromedial and one dorsal seta. Mid tibia with ventroapical seta. Hind tibia sometimes with one or two distinct anterodistal setae. Hind basitarsomere with longer basal hairs and bare elongate anterobasal recess.
Head. Antenna elbowed, bases approximate; pedicel rounded, with wide, deep seam to dorsum, dividing small- er outer surface from broader, convex inner surface; first flagellomere elongate, narrower than pedicel; arista unsegmented and sparsely long plumose, with rays becoming shorter apically and sparser ventrally to base (Fig. 85). Head short and broad, nearly twice width of thorax; frons narrow (slightly more than half width of eye), smooth, flat, horizontal and slightly constricted posteriorly, with ocellar triangle not evident; orbital plate not delimited, but evident as short, pale posteromedial region that tapers at both ends (Fig. 86); ocelli at vertex; ptilinal suture very short, without long lateral arms. Back of head concave dorsomedially and with setulose bulge above foramen. Lunule absent. Face strongly convex ventrally (similar to Psilidae but broadly rounded) and fused to parafacial (suture sometimes evident in part); face and parafacial sometimes strongly swollen laterally, forming medial groove; gena broad, not distinct from face, and both it and venter of postgena mostly sunken beneath head and facing ventrally; buccal cavity ovate, relatively small, sharply delimited; clypeus longer than wide, rounded with apex pointed; mouthparts reduced.
Thorax. Thorax elongate and narrow, without pronotal “neck”, but with shallow medial and lateral carinae displacing cervical sclerites. Precoxal bridge present; bulging laterally, with medial groove, posterior surface raised (Fig. 84); prosternum velvety, relatively broad, setose laterally; postmetacoxal bridge high if present. Proepisternum broad, bulging anterodorsally, sometimes fused to postpronotum. Suture between katepisternum and anepisternum only present for a short distance posteriorly, partially evident anteriorly as darker line. Suture between katatergite and anepimeron sunken; posteromedial margin of mediotergite extended as lobe that meets longer band-like anteromedial extension of T1. Greater ampulla present. Anterior thoracic spiracle laterally compressed, ventrally with groove terminating in small, deep pit (similar to some Psilidae); tubercle present below posterior spiracle. Broad membranous space separating anepisternum and anepimeron.
Wing. (Fig. 402) Wing slender; anal lobe and alula strongly reduced; apically infuscated. Calypter linear, with several long hairs. Cells bm and cu a (slightly shorter) ending approximately at apex of Sc; cells cu a and bm, and adjoining wing margin, without microsetulae. Cell dm narrow, slightly wider apically. Costa unbroken; subcosta complete; R 4+5 and M 1 slightly convergent. M 4 ending before wing margin, CuA+CuP ending closer to margin.
Legs. Hind femur long, slightly swollen (Fig. 83). Femora ventrally with paired rows of thickened setae that may appear spine-like (sometimes reduced to base); spines darker and larger on the more posterior legs; fore and mid femora with rows of usually 4–6 spinose setae (smaller and fewer on posterior row), and hind femur with 3–6 spinulose setae on anterior row and 8–12 on tubercles on posterior row.
Abdomen. Abdomen straight, narrow (narrowest medially on segment 2), petiolate with apex slightly clavate. T1 and S1 broadly emarginated anteriorly to provide membranous space that folds to meet thorax when abdomen angled. T1 completely fused to T2, lateral margins evident (Fig. 89); S1 with reduced setation; T1+2 nearly as long as remining pregenitalic segments; T3 and S3 slightly longer than wide, tergites and sternites 4–6 wider than long, becoming progressively shorter posterioly. Spiracles 1–5 in membrane, spiracles 6 and 7 enclosed by tergite.
Female genitalia. (Figs 67–70) T6 and S6 fused with suture not evident. Segments 7, 8 and 10 very short with sclerites broad; S8 bare in material examined; T10 larger than S10. Cerci very short and broad. Spermathecae 1 + 2, with paired spermathecae on short stalks; spermathecae and apical section of ducts pigmented; spermathecae with sparse, minute pits.
Male genitalia. (Figs 89–97) T6 fused to S8, which is nearly symmetrical; S6 and S7 absent, with pregenital sclerites membranous ventrally. Terminalia past T8 strongly asymmetrical; components of internal genitalia of tentative homology. Phallapodeme present (not absent, as stated in McAlpine (1997)). Epandrium subspherical, atrophied on left side, oblique; right anteroventral corner produced. Left surstylus small, pale, subrectangular; right surstylus larger, darker, bulbous. Subepandrial sclerite small, near ventral margin of epandrium and with one pair of small separate sclerites. Hypandrium bare, with medial bridge weakly sclerotized, flat and minutely setose; arms meeting dorsally; approximately U-shaped with right side strongly elaborated into several different posterior lobes and thin anterior carina. Phallapodeme short, carinate. Postgonite absent. Right pregonite absent; left pregonite (perhaps further elaboration of hypandrium?) flat, short and with more sclerotized margin. Epiphallus absent. Distiphal- lus short, stout, narrowest at base, and with cylindrical subbasal process with apical hairs; basiphallus produced as long left lateral lobe. Ejaculatory apodeme with broad, pale blade, and short thin stalk with narrow base; sperm pump cup-shaped with dark basal ring.
description: Published as part of Lonsdale, Owen, 2020, Family groups of Diopsoidea and Nerioidea (Diptera: Schizophora) - Definition, history and relationships, pp. 1-177 in Zootaxa 4735 (1) on pages 20-22, DOI: 10.11646/zootaxa.4735.1.1, http://zenodo.org/record/3670762