Asteia nigriceps Bezzi

Grimaldi, David A., 2009, The Asteioinea of Fiji (Insecta: Diptera: Periscelididae, Asteiidae, Xenasteiidae), American Museum Novitates 3671, pp. 1-60 : 39-41

Asteia nigriceps Bezzi

Figure 23 , 25

Asteia nigriceps Bezzi, 1928: 160 ; Sabrosky, 1957: 37 (discussion), 1989 (catalog).

DIAGNOSIS: In the Fijian fauna nigriceps is most similar to Asteia pleurovitta , except that nigriceps does not have a dark pleural stripe, it has a dark frons with well-developed ocellar setae, two (vs. three) pairs of dorsocentrals, and possesses 2 short rows of acrostichals. Separated from A. acrostichalis Sabrosky ( Caroline Islands), which also distinctively possesses acrostichals, by the new species having a flatter head, shallow postgena, and greatest length of eye being oblique instead of nearly vertical (cf. Sabrosky, 1957: fig. 1).

DESCRIPTION: ThL 5 0.51. Body coloration: Head with frons entirely dark brown, frontal vitta finely striate and dull, frontoorbital plates bare and shiny; ocelli white. Pedicel and most of face dark brown, face with white transverse stripe adjacent to oral margin. Cheeks, proboscis, palps, clypeus cream colored; postgena and postocciput dark brown. Eyes light red. Mesoscutum entirely brown, scutellum and mesonotum entirely white. Pleura and legs entirely cream colored. Wing hyaline; halter with stem light, knob very light brown. Dorsum of abdominal segments I–XI and entirety of abdominal segments IV–VI brown, remainder of abdomen including terminal segments cream colored. All setae black or dark except for light katepisternal setae.

Head and abdomen: Frons flat, but of moderate length. One, reclinate fronto-orbital seta present; anterior to this is row of 3 fine, short setae. Slightly above ptilinal suture is small pair of short, stout, cruciate interfrontal setae. Pair of long, fine ocellar setae present; postocellars either lost or very minute. Inner and outer vertical well-developed, OVs ca. 1.3X length of IVs. Antennal pedicel with long dorsal setae (rest of antennae lost in new specimen). Face flat. Eyes bare, greatest length oblique to longitudinal axis of body. Proboscis, palpi, wings, legs as for A. pleurovitta . Scutum with very slight microtomentum, surface not shiny or polished. Two pairs of dorsocentrals; anterior pair slightly shorter than posterior pair. Two short rows acrostichals of 3–4 setulae each on anterior half of scutum, end at level of anterior DCs. Row of 4–5 similar setulae anterior to each anterior DC, and oblique row of 3 setulae anterior to mesoscutal suture. No postpronotal or supraalar setae, 2 notopleural setae. Female abdomen with sternites vestigial; tergites reduced in size and lightly sclerotized. Male terminalia: Epandrium short, broad; surstyli symmetrical and forcipate, with narrow tips; pair of broad, flangelike sclerites inside each surstylus and below cerci. Hypandrium Yshaped; aedeagal apodeme long and narrow; ejaculatory apodeme large, palette shaped; aedeagus short, sclerotized, as figured.

TYPE: As cited by Bezzi (1928) holotype, male: FIJI: Loloti , 18.ix.1921; an additional specimen from Lautoka Mts. , 1.ix.1921 (W. Greenwood). In NHM, London (examined). Body of the type is intact, but the setae and antennae are lost, and some details are obscured by glue .

MATERIAL EXAMINED: Female (not dissect- ed), FIJI: Viti Levu, Vuda Prov. , Koroyanitu N.H.P., Gavuione Trail. FJ-1 Malaise [trap] in montane forest. 21.IX–7.X.2002, M. Irwin, E. Schlinger, M. Tokota’a, 17 ° 409S–177 ° 339E, 450 m. FBA 005317; Koroyanitu EcoPark, Mt. Evans , 1 km E. Abaca, Kokabula Trail : 217.667 °, 177.55 °, 800 m, 12.X–19.X.2002, Malaise MO 1, M. Tokota’a, FBA202857 (male, dissected: no. 62). Taveuni: Cakaudrove Prov.: 3.2 km NW Lavena Vlg., Mt. Koronibuabua, 217 m, 26. III –9. IV. 04, Malaise 3, Schlinger and Tokota’a, 16.855 ° S, 179.89 ° W, FBA145571 (male). In BPBM and AMNH .

COMMENTS: Bezzi’s original description mentions this species as a shiny black instead of brown; otherwise, the new specimens agree in all respects with his description and that of Sabrosky (1956). Asteia nigriceps appears most closely related to A. pleurovitta based on the similar body coloration and the distinctive pair of small, cruciate profrontal setae on the frons. Significant differences are that A. nigriceps has two instead of three pairs of dorsocentrals as well as possessing acrostichal setulae. Interestingly, all three of the Asteia species described above were collected in the same Malaise trap in Koroyanitu National Historic Park on Viti Levu.

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. 25. Male terminalia of Asteia nigriceps Bezzi. A. Epandrium and genitalia, posterior view. B. Ejaculatory apodeme, lateral view. C. Aedeagus, oblique posterior view. All to the same scale.