Apocephalus mesacanthus Brown & LeBrun

Brown, Brian V., 2012, Revision of the Apocephalus mucronatus group of ant decapitating flies (Diptera: Phoridae), Zootaxa 3413, pp. 19-28 : 22-24

Apocephalus mesacanthus Brown & LeBrun

( Figs. 5 , 12 , 19 , 26 )

Apocephalus mesacanthus Brown & LeBrun 2010: 17 , figs. 30, 34.

Holotype. Ƥ, USA: Arizona: Cochise Co., Greenhouse Trail, 31.88° N, 109.27°W, 24–25.ix.1998, E. LeBrun, Malaise trap, 2000 m [barcode: LACM ENT 055140] ( LACM; examined).

Species recognition. Abdominal tergites plain brown; tergite six lacking posterior row of strong setae. Oviscape with long dorsomedian process. Ventral sclerite of oviscape elongate. This species is most similar to the other North American species, A. missouriensis , from which it differs by characters given in the key.

Emended description. Body length 1.5–1.6 mm. Frons brown, mean frontal width 0.50, range 0.49–0.50. Median furrow present. Supra-antennal setae absent. Ventral interfrontal setae near midline. Ocelli normal sized. Ommatidia normal sized. Flagellomere 1 pyriform, brownish yellow, apically brown. Palpus yellow, normal sized. Scutum light brown. Scutellum light brown, anterior seta about one-third length of posterior seta. Pleuron light brown. Anepisternum bare. Wing normal sized, mean costal length 0.40, range 0.39–0.42. Halter with yellow stem and brown knob. Abdominal tergites brown, normal sized. Tergite 6 about as broad as tergite 5, entire, apical margin straight, posterior margin with small setae. Venter of abdomen yellowish brown, dark grey near tergites. Venter of segment 6 with large sclerite, with row of long thick setae, and few smaller anterolaterally. Oviscape elongate oval, anterior process short, broadly rounded, large lateral setae absent, with scattered dorsolateral setulae on apical one-quarter. Dorsal process long, ending near apex of oviscape. Apex broadly truncate, relatively straight, lacking dorsoapical setae. Venter with apical sclerite with triangular darkening posterolaterally; separated midventral sclerite elongate oval, with few thin setae near apex. Intersegment 7–8 with short rectangular sclerotization issuing laterally from oviscape. Anterior arms of stylet anteriorly parallel, well separated, relatively flat.

Distribution. Southwestern United States.

Newly examined material. USA: New Mexico: Whitewater Canyon, 33.36°N, 108.06°W, 1Ƥ, 1.vi.1972, W.W. Wirth, Malaise trap ( USNM); Texas: Oak Canyon, Big Bend NP, 29.28°N, 103.33°W, 1425 m, 5–11.iv.1993, J.Gelhaus, Malaise trap ( LACM).

Figures

FIGURES 3 – 9. Female Apocephalus species, oviscapes, dorsal.

FIGURES 10 – 16. Female Apocephalus species, oviscapes, ventral.

FIGURES 17 – 23. Female Apocephalus species, tergite 6, dorsal.

FIGURES 24 – 29. Female Apocephalus species, segment 6, ventral.