Silba kadavu, Macgowan, Iain, 2014

Macgowan, Iain, 2014, The Lonchaeidae of Fiji (Diptera: Schizophora), Zootaxa 3814 (4), pp. 537-552 : 542-544

Silba kadavu sp. nov.

Description. Male: Head. Eyes bare. Frons matt black with numerous short frontal and interfrontal setulae approximately 10% length of orbital seta. Orbital plate bare, subshining black, dulled by micro sculpture, bare apart from orbital seta. Lunule setulose with dark ground colour, light grey dusted, this dusting extending to face and parafacials. Antennae black, 1st antennal flagellomere 2.5x as long as deep. Arista with short plumosity which at maximum extent is approximately 0.5x depth of 1st flagellomere. Anterior genal setulae in a single row along mouth margin, anterior 4 well separated from the rest, on right side these almost all same length but on right basal setulae much stronger than the others.

Thorax: Dorsum and sclerites subshining black, covered with fine dusting, Anepisternum with 2 strong anterodorsal setae and 3 posterior, remainder of sclerite with scattered long black setulae. Katepisternum with two strong dorsocentral setae, anterior slightly shorter and weaker than posterior, otherwise sclerite bare. Proepimeron with one setulae. Scutellum quite heavily dusted, Holotype with marginal setae and setulae missing (Paratype - between apical setae with 2 small setulae, between lateral and apical setae with 2 setulae). Calypteres white with white fringe. Wings almost clear, wing length 3.0mm. Legs entirely black including ventral fringe of anterior and posterior basal tarsomeres.

Male terminalia: ( Figs. 24–27 ). In lateral view epandrium 1.5x wider than high, bearing setulae posteroventrally; cerci large and rectangular in shape, bearing strong setulae along posterior and ventral margins. Surstyli projecting beyond the shell of epandrium, in internal view 7 black peg-like prensisetae present on basal plate, one small setula present below the basal prensisetae, outer lobe disc-like, margin bearing a row of 10–12 strong spine-like setulae. Phallus U-shaped, relatively slender with a few small setulae near base, basal lobe large with bifurcated apex.

Type material: Holotype ♂. FIJI ; Kadavu island, 0.25Km SW Solodamu village, Moanakaka bird sanctuary, 19.078°S 178.121°E, alt. 60m, Malaise trap, 15.ii–7-iii.2004. Schlinger & Tokota’a.

Paratype; 1 male with the same data as the Holotype. Lakemba, Tubou, 0– 10m., 11.ii.1970, N.L.H. Krauss, 1 male.

Differential diagnosis: In the structure of the phallus this species shows some similarities to Silba rotherayi MacGowan, 2005 from Malaysia but in that species the basal lobe is more distinctly divided. Other differences in the male genitalia include the presence of long pointed setae at the base of the cerci and long pointed prensisetae in S. rotherayi .

Figures

FIGURES 24 – 27. Silba kadavu sp. nov. 24. Epandrium and associated structures lateral view. 25. Same ventral view. 26. Phallus lateral view. 27. Phallus ventral view.