Asteia pleurovitta, Grimaldi, 2009

Grimaldi, David A., 2009, The Asteioinea of Fiji (Insecta: Diptera: Periscelididae, Asteiidae, Xenasteiidae), American Museum Novitates 3671, pp. 1-60 : 41-43

Asteia pleurovitta , new species

Figures 23 , 24 , 27

DIAGNOSIS: Head somewhat flattened, frons light, face with transverse white band in female, male with light face and brown stripe on oral margin; ocellar setae minute (barely visible); mesoscutum with 3 pairs dorsocentrals, mostly light brown, with whitish posterior portion adjacent to white scutellum; pleura cream colored except for dark brown longitudinal stripe just ventral to notopleural suture; legs light, halter dark brown; male terminalia with surstylus large and crescentic, aedeagus with bulbous distal end. Similar to Asteia pleurovittata , n. sp. (for differences, see diagnosis below).

DESCRIPTION: ThL 5 0.51. Body coloration: Frons graded anterior to posterior from dark ochre to cream, with area between ocelli dark brown; ocelli light. Female face having thin stripe of dark brown on oral margin, bordered by white transverse band; dorsal half ochre; male with whitish face and thin, dark brown stipe on oral margin. Scape, pedicel, dorsal half of basal flagellomere dark brown; ventral half of basal flagellomere ochre. Eyes pink/light red. Cheeks, proboscis, clypeus, palps entirely cream colored; postgena dark brown. Mesoscutum mostly dark brown, with cream colored triangle on posterior half blended into creamy scutellum; lateral corners of scutellum light brown; postnotum cream. Pleura light cream color, with dark brown stripe from anterior margin of scutum to wing base, just ventral to notopleural suture and including portions of wing base. Legs entirely light. Halter base light; middle of stem and all of know dark brown. Tergites mostly light brown, with lateral portions of tIII in female dark brown. All setae blackish, except for very light setae on katepisternum.

Head: Flattened, depth ca. 0.6X the length; longest axis of eye nearly in line with body axis. Frons long, flat; frontal vittae very finely striate; single pair of stout, reclinate fronto-orbital setae, lie anterior to midlength of frons, lengths about equal to that of verticals; fine, scattered setulae on frons near ptilinal suture, especially laterally; a distinctive pair of fine, cruciate setae on anterior margin of frons (the profrontals), lengths ca. 0.4X that of FOs. Ocellar setae highly reduced to setulae barely longer than diameter of ocellus. Postocellar setae minute. Inner and outer vertical setae well developed, thick, OVs slightly longer and IVs. Antennae with bases displaced laterally, such that lateral surfaces face head and mesal surfaces face forward; pedicel with single, stout dorsal seta and small group fine, light setulae on ventromesal surface; basal flagellomere nearly circular in broad view, with proximal notch into which fits pedicel attachment. Arista with 3 dorsal, 2 ventral branches (not including apical fork), longest branch ca. 0.4X length of entire arista. Face flat, with very slight vertical ridge on dorsal half; face slightly microtomentose, not polished. Single pair vibrissae present, well developed (length about equal to that of FOs, but slightly thinner); 2 fine setae ventral to vibrissae. Cheek very shallow; eye is oblong, bare of interfacetal setulae. Palp long, slender, slightly curved, with approximately 5 fine setae on ventral edge.

Thorax: Mesoscutum not arched or domed, with three pairs stout dorsocentrals; middle pair of dorsocentrals equidistant between anterior and posterior pairs. Mesoscutum with sparse, light pollinosity, surface not polished or shiny; no acrostichals. Dorsocentrals slightly shorter than vertical setae. No postpronotal or supraalar setae; 2 notopleural setae (slightly finer and shorter than dorsocentrals). Scutellum with two pairs setae, anterior pair very small and fine, length ca. 0.2X that of posterior scutellars; posterior scutellars large, slightly divergent, somewhat erect. Katepisternum with two, very fine, light setae near dorsal margin. Legs without distinctive setation, except on tarsi. Fore- and midtarsi with ventral rows gold, stiff setulae; dorsally each tarsomere with pair of short, stout, black setae. Wing with venation typical of Asteia (see above), notable exceptions light-colored C, no thickening of vein R 1 at apex, and vein Cu evanescent for apical half. Alula completely lost, anal lobe reduced (anal margin divergent with course of vein CuA 1, not parallel). Abdomen almost entirely membranous, tergites reduced to small, lightly sclerotized sclerites; sternites largely lost. Male terminalia: Epandrium light colored and lightly sclerotized, cerci small and mostly membranous; surstylus large, with large, pointed mesal lobe that makes surstylus virtually crescentic in shape, inner edge of which is lined with fine, spiculelike setulae. Aedeagus typically elaborate, sclerotized, twisted, but with apical portion distinctively swollen (as figured).

TYPES: Holotype male (dissected, no. 51): FIJI: Viti Levu , Vuda Prov., Koroyanitu N.H.P., Savuione Trail. FJ-1 Malaise. 21.IX– 7.X.2002. M. Irwin, E. Schlinger, M. Tokota’a, 17 ° 409S–177 ° 339E, 450 m, FBA018202. In BPBM. Paratypes: female (not dissected), same, FBA 018185; Koroyanitu EcoPark , 0.5 km N Abaca Vlg. , 800 m., 7–12.X.2002, Malaise 1, Schlinger and Tokota’a, 17.667 ° S, 177.55 ° E, FBA093688 (female), 093689 (male), 093690 (female) (in BPBM and AMNH) .

ETYMOLOGY: From pleura and Latin vitta (‘‘stripe’’), in reference to the dark brown stripe on the upper portion of the pleuron.

COMMENTS: As given in the diagnosis above, this is a very distinctive species.

Figures

Fig. 23. Portions of the left lateral habitus of Fiji Asteia (Asteiidae) (to the same scale). A. A. rotundiscuta, n. sp. B. A. pleurovitta, n. sp. C. A. pleurovittata, n. sp. D. A. nigriceps Bezzi.

Fig. 24. Wings (entire and detail of bases) of Fiji Asteiidae and Xenasteiidae. A, B. Asteia pleurovitta, n. sp. C, D. Asteia vitiensis, n. sp. E, F. Xenasteia fijiana, n. sp. A, C, E to same scale; B, D, F to same scale.

Fig. 27. Male terminalia of Asteia pleurovitta (A), and A. pleurovittata (B). A. Epandrium, surstyli, and aedeagus, oblique posterior view. B. Epandrium, surstyli, aedeagus, and ejaculatory apodeme, oblique posterior view.