Austalis rhina Thompson

Thompson, F. Christian, 2003, Austalis, a new genus of flower flies (Diptera: Syrphidae) with revisionary notes on related genera, Zootaxa 246, pp. 1-19 : 8-9

Austalis rhina Thompson , sp. nov.

Male.̶ Head ( Fig. 7): metallic greenish black; face silvery-white pollinose and pilose laterally and ventrad antenna, shiny and bare medially and along oral margin, produced strongly anteriorly, with low indistinct tubercle; gena very narrow, silver-white pollinose and pilose; lunule orange; frons narrowly silvery-white pollinose laterally, shiny medially, black pilose; vertex dull brownish-black pollinose, black pilose; eyes broadly dichoptic, separated by 1/4 head width, bare; antenna orange except basoflagellomere brownish dorsally, black pilose on basal segments, basoflagellomere with large basoventral sensory pit on inner side; arista orange, bare; occiput silvery pilose and pollinose on ventral 2/3, becoming sparsely pollinose on dorsal 1/3 with a row of black cilia.

Thorax. Metallic greenish-black; scutum shiny except for dull black pollinose vittae and sparsely silvery pollinose on postpronotum and notopleuron, with a pair of narrow submedial pollinose vittae extending about 2/3 distance to scutellum, with a broader and interrupted sublateral pollinose vittae; postalar callus yellow pilose; scutellum shiny, yellow pilose; pleuron sparsely gray pollinose, yellow pilose; calypter white except apically brownish black on ventral margin; plumula white; halter orange; mesothoracic spiracular fringe brown; metathoracic spiracular fringe brown. Legs: Coxae dark greenish black, silvery pollinose, yellow pilose; trochanter brownish black, shiny, yellow pilose; pro & mesofemora dark brownish black on basal 1/3, orange apically, orange pilose; metafemur swollen, dark greenish black on basal 4/5, orange apically, shiny, yellow pilose except for black apicoventral spinose pile; tibiae orange, orange pilose; pro & mesotarsi orange except apical tarsomeres slightly brownish dorsally, orange pilose; metatarsus brownish dorsally, orange ventrally, black pilose. Wing: tegula orange; basicosta orange and black pilose; microtrichose except bare basomedially; bare apical 1/2 of cell R1, apical 4/5 of cell R2+3, apical 2/3 of cell R4+5, apical 1/3 of DM and along apical and posterior margin of cell CuA1; alula bare except apical 1/2 microtrichose.

Abdomen: dark green, shiny and with dull black pollinose maculae; 1st tergum shiny except medial 1/3, yellow pilose; 2nd tergum black pollinose except triangular shiny basolateral macula and apical margin, yellow pilose except short appressed black pilose medially; 3rd & 4th terga shiny basally and apically, black pollinose medially, orange pilose on shiny areas and black pilose elsewhere; male genitalia black, dull pollinose, yellow pilose; sterna metallic green, shiny except sparsely pollinose on 2nd sternum, yellow pilose. Male genitalia ( Fig. 6 ).

Female.‾Similar except for normal sexual dimorphism, barer wing (basal 2/3 of cell C, all of cells R1, R2+3, R4+5, basomedial 2/3 of DM, basomedially of cell CuP & CuA1); 5th tergum dark green, dull pollinose except narrowly shiny apically.

Types. Holotype male from SOLOMON ISLANDS: Gizo Island, Gizo, 0­200 m, Dec 1975, light trap, N. L. H. Kraus deposited in the Bishop Museum, Honolulu. Paratypes. 4 males with the same data as the holotype (BPBM & USNM); Gizo Island, Gizo, January 1974, N. L. H. Kraus (2 male, 3 females, BMNH & USNM); ..., Gizo, 0­140 m, Dec 1980, N. L. H. Krauss (2 males, BPBM & USNM). Buka Island, Buka Agricultural Station, 6­10 Dec 1959, T. C. Maa (2 males, 15 females, BPBM). Bougainville, Simba Mission, 29 June 1956, E. J. Ford, Jr. (4 females, BPBM), ..., 2 July 1956, E. J. Ford, Jr. (1 female, BPBM); ..., Arawa, 4 km n of Kleta, 9­13 July 1965, R. W. Crosskey (1 female, BMNH); ..., Kieta, 26 June 1956, E. J. Ford, Jr. (1 male, BPBM). New Georgia Island, Munda, 0­200 m, Nov 1975, N. L. H. Krauss (1 male, BPBM). Santa Isabel, Tamatahi, 450 m, 3 July 1960, C. W. O’Brien (1 male, 3 females, BPBM). Florida Island Group, Hanavaivine, Small Nggela, 15 Sept 1960, C. W. O'Brien (1 female, BPBM); ..., Halteta, 200­250 m, 10 Oct 1964, R. Straatman, Malaise trap (1 female, BPBM). Guadalcanal, Poha, Sept 1944, J. Laffoon, Cat.# 191 (1 female, USNM).

Etymology: The epithet, rhina , is an adjective from the Greek for nose and refers to the facial shape of the species.

Austalis rhina is readily distinguished from other species by its dichoptic males and snout­like face. This striking species is restricted to the Solomon Islands.

Figures

FIGURES 1 ­ 6. 1 ­ 4. Thoracic pleurae of eristaline flies. Arrows point to the critical areas, 1. Austalis rhina, sp. nov., arrow pointing to bare anterodorsal area of the posterior anepimeron, 2. Eristalinus aeneus (Scopoli), arrow pointing to pilose katepimeron, 3. Eristalis (Eoseristalis) arbustorum (Linnaeus), arrow pointing bare posterior anepimeron and meron, 4. Eristalis (E.) tenax (Linnaeus), arrow pointing to bare posterior anepimeron, but pilose katepimeron; 5. Thorax, dorsal view, Eristalinus aeneus (Scopoli), arrow pointing to postalar pile turf; 6. Male genitalia, lateral view, Austalis rhina, sp. nov. Figures 1 ­ 5 are from Thompson & Rotheray (1998).