Metaparaclius Becker

SCOTT E. BROOKS, 2005, Systematics and phylogeny of Dolichopodinae (Diptera: Dolichopodidae), Zootaxa 857, pp. 1-158 : 74-77

Genus Metaparaclius Becker

( Fig. 17 A–F)

Metaparaclius Becker, 1922b: 33 . Type species: Metaparaclius subapicalis Becker [Australasian], by monotypy.

Recognition. Metaparaclius can be distinguished by the distal part of M, which is strongly bent anteriorly, convex and strongly convergent with R4+5, scape of male enlarged and thickened, pedicel reduced, arista subapical, bare and elongate with an apical lamella. Male and female M. australiensis are further distinguished by a dark black spot above the notopleuron and 2 strong setae on the proepisternum in front of the anterior spiracle.

Description. Head: Vertex not excavated, 1 pair of strong vertical setae, stronger than postverticals. Frons about 2 x wider than high, concave near base of antennae especially in male, sides subparallel. Face and clypeus very narrow in male, broad in female; clypeus flat, triangular in male, strongly and evenly produced in female, lower margin straight, not reaching lower eye margin. Palp and proboscis smaller in male; palp ovoid with subtriangular apex, with fine setae on apical third and 1 stronger apical seta. Antenna: Male scape greatly enlarged, elongate and thick, with weak medioventral process, M. australensis with 6–8 stronger setae on apicodorsal margin in addition to usual dorsal setae; pedicel reduced and funnel­shaped; first flagellomere conical or subtriangular, 2.0–2.5 x as long as wide, pointed apically, with weak dorsal seta in M. australiensis ; arista subapical, 1 or 2 segmented, basal segment very short when present, distal segment elongate, bare, with apical lamella. Female scape short, subconical, setose dorsally, with well­developed acute medioventral process; pedicel short; first flagellomere rounded; arista dorsal. Postvertical setae stronger than uppermost pair of postoculars.

Thorax: Acrostichals biserial; 5–6 dorsocentrals, aligned; 1 strong outer posthumeral, 1 weaker inner posthumeral; 2 notopleurals; 1 presutural; 1 sutural; 2 supraalars; 1 postalar. Metaparaclius australiensis with distinct dark metallic spot above notopleuron. Upper part of propleuron of M. australiensis with 2 strong black setae and several fine hairs; lower part of propleuron with 1 strong prothoracic seta and fine hairs; pleural surface in front of posterior spiracle bare; metepisternum with fine hairs. Scutellum with 1 strong inner seta and a weak outer seta on lateral margin.

Legs: Pulvilli developed normally on all legs. Midleg: Femur with 1 anterodorsal preapical seta. Hindleg: Coxa with strong lateral seta near middle; femur with 1 anterodorsal preapical seta; tibia of male M. australiensis with weak ridge­like process posteroapically; basitarsus shorter than second tarsomere, with 1–2 short anterior setae, 4–5 short ventral setae, male M. australiensis with bulging dentiform projection posterobasally.

Wing: R2+3 nearly straight; R4+5 straight with posterior bend apically; distal section of M beyond crossvein dm­cu with obtuse to 90° anterior bend, arcuate and strongly convergent with R4+5, ending well before wing apex; crossvein dm­cu equal to or slightly longer than distal portion of CuA1.

Abdomen: Subconical. Male: T6 bare; S2 unmodified; S3 weakly emarginate posteriorly; S4–S6 mainly membranous, S4 and S6 weakly sclerotized along lateral and anterior margins; segment 7 forming elongate peduncle, about as long as segments 5 and 6 combined; S8 heart­shaped, narrowed proximally, setose. Hypopygium ( Fig. 17 A–D): Epandrium subrectangular in lateral view, about 1.7 x as long as high; foramen positioned anterolaterally, well­separated from base of cerci; basiventral epandrial lobe not developed, basiventral epandrial seta near apex of ventral margin, slightly anterior to apicoventral epandrial lobe; apicoventral epandrial lobe well­developed with subquadrate ventral portion bearing 2 strong setae, dorsal portion rounded, keel­like, with seta on ventral surface. Surstylus bilobed, both lobes about equal in length, long, thin. Ventral lobe digitiform with 1 short, weak dorsal seta near middle and several setae near apex. Dorsal lobe with apex enlarged and laterally flattened, dorsal surface emarginate preapically with keel­like projection. Postgonite with anteroventral portion well­sclerotized, laterally flattened ( Fig. 17 B), with anterodorsal and ventral margin flared laterally; posterodorsal portion welldeveloped, widened and tripartite apically ( Fig. 17 D). Proctiger brushes absent. Cercus large, oval to subquadrate, M. australiensis with fine branched setae on apical margin ( Fig. 17 A). Hypandrium elongate, thin, free laterally, connected to epandrium basiventrally; hypandrial arms not connected to hypandrium, fused to ventral margin of epandrium ( Fig. 17 B); hypandrial apodeme well­developed. Sperm pump small; ejaculatory apodeme welldeveloped, laterally flattened, basal sclerite of sperm pump U­shaped in dorsal view, with long, thin lateral arms. Phallus thin, apical portion with 2 weak dentiform processes. Female ( Fig. 17 E,F): T6, S6, T7 and S7 undivided, T8 and S8 divided medially, tergite and sternite not fused anterolaterally. Furca present, narrow and triangular. T10 divided medially into hemitergites each bearing 4 spines.

Geographical Distribution. Metaparaclius includes two Australasian species, M. subapicalis from New Guinea and M. australiensis from northern Australia.

Phylogenetic Relationships. Until additional specimens of the type species, M. subapicalis , are identified (see “Remarks”), the systematic position and monophyly of this genus will remain ambiguous. Based on the cladistic analysis, Metaparaclius australiensis is related to a lineage of Oriental species including “ Polymedon ” inopinatus, Paraclius abbreviatus , P. pilosellus and related species (see “ Tachytrechus genus group” section above). Metaparaclius australiensis also appears to be closely related to the Australasian species Paraclius neglectus , which has a similarly modified postgonite, similar overall genitalic structure and several strong setae on the upper part of the propleuron.

Remarks. Becker deposited the unique male holotype of Metaparaclius subapicalis in the Hungarian Museum, which was destroyed during the Hungarian Revolution of 1956 (M. Földvàri pers. comm.). No other specimens are known.

Material Examined. Metaparaclius australiensis Parent , [AU]: ɗ holotype ( BMNH); 5ɗ, 4Ψ ( CNC); 3ɗ, 3Ψ (LEM).

Figures

FIGURE 17. Metaparaclius australiensis: (A) Male genitalia, left lateral view (external); (B) Male genitalia, left lateral view (internal); (C) Male genitalia, postgonite, dorsal view of apex; (D) Male genitalia, ventral view (postgonite, surstylus and cerci not shown); (E) Female genitalia, dorsal view; (F) Female genitalia, left lateral view.