Lonchaea malekula, MacGowan, 2021

Macgowan, Iain, 2021, The Lonchaeidae of Vanuatu (Diptera: Schizophora), Zootaxa 4926 (3), pp. 342-362 : 351-352

Lonchaea malekula sp. nov. ( Figures 26-28 )

Description. MALE: Body length 4.4m.

Head: Eyes bare. Frons sooty black along eye margins, centrally sub-shining black, dulled by microsculpture, ratio of width at anterior margin to eye width 0.6:1. Frontal and interfrontal setulae short, approximately 0.2x as long as orbital seta, becoming longer near anterior margin. Lunule setulose, ground colour dark brown, when seen from above covered in silver pollinosity as is face and to a lesser extent parafacials. Antennae black, pedicel dull brown, postpedicel broadly orange brown on medial base, length to depth ratio 2.7:1. Arista plumose, ratio of plumosity at its maximum to depth of postpedicel 0.9:1. Anterior genal setulae in a single row of six along mouth margin

Thorax: scutum shining black, slightly dulled dorsally, covered in very short setulae approximately 0.1x length of orbital seta. Anepisternum and katepisternum glittering black, almost brassy. Anepisternum with two anterior and three? posterior setae, remainder of sclerite with a scattering of short setulae. Katepisternum, one seta near dorsal margin, short setulae present around and posterior to it. One seta on both proepimeron and proepisternum. Scutellum, disc sub-shining black slightly pollinose, covered with sparse short setulae, no strong marginal setulae apparent. Calypteres and fringe pale yellow. Wings, almost clear, only faintly fumose anteriorly, veins brownishblack. Wing length 4.2mm. Legs entirely black, mid tibia on apical 2/3 with an anteroventral fringe of numerous long setulae, these longer than width of tibia, this fringe continuing onto t1 as a row of approximately 12 regularly spaced setulae ( Fig. 9 ).

Male terminalia: In lateral view epandrium rather rectangular, width slightly less than 2x height, with a small rounded posteroventral projection, numerous long setae posteriorly and a covering of short dense setulae on anteroventral quadrant. Cerci 0.5x as high as epandrium, rather rectangular with a small apical projection, approximately six stiff, almost spine-like setae along posterior margin. Inner view; Surstyli, enclosed within shell of epandrium with numerous setae on inner surface, these extending beyond margin of epandrium antero-ventrally. Phallus, bisegmented, extremely long and thin reaching to apex of cerci, basiphallus slightly sinuous, distiphallus slightly corrugated near apex.

Type material. Holotype ♂: VANUATU: Malekula , ii.1930, L. E. Cheesman ( BMNH).

Paratypes: Malekula, Lakatoro, 23.ix.1967, J. & M. Sedlacek, 1♂. Pentecost Island . 200-500m, 27.iii.1964, R . Straatman, 1♂ (both BPBM).

Etymology. The specific epithet is derived from the island of Malekula on which the Holotype was captured.

Remarks. This species with its plumose arista shows similarities with the four Lonchaea species apparently indigenous to Fiji ( MacGowan, 2014). In particular, with an epandrium rectangular and higher than wide, small cerci and bi-segmented phallus, this species has closest affinities with L. vanua MacGowan, 2014 . L. malekula can however be easily distinguished from L. vanua by the setulose scutellar disc, anteroventral fringe on mid tibiae, multiple strong setulae on inner surface of the surstylus and a substantially longer phallus.

Figures

FIGS. 26-28. Lonchaea malekula sp. nov. 26. Epandrium and associated structures, lateral view. 27. Surstylus, internal view. 28. Tibia and basal tarsomeres of mid leg.

FIGURES 9-12. Lamprolonchaea photinia McAlpine, 1964. 9. Epandrium and associated structures, lateral view. 10. Phallus, lateral view. 11. Surstylar plate, ventral view. 12. Surstylus, medial surface.