Ptilotophallos megasathe Webb, 2005

Webb, Donald W., 2005, New Genera of Neotropical Therevidae (Insecta: Diptera), Zootaxa 1091 (1), pp. 1-26 : 13-17

Ptilotophallos megasathe Webb spec. nov.

( Figs. 22–31 ).

Etymology. mega (Greek) = large, sathe (Greek) = penis. This name refers to the enlarged aedeagus of the male and is used as a noun in apposition.

Diagnosis. Ptilotophallos megasathe can be separated from other South American genera by the emarginate medial margin of the gonocoxite ( Fig. 25 ) into which fits the lateral margin of the basiphallus and the autapomorphic characteristic of possessing broad, wing­like flanges apicolateral on the male distiphallus ( Fig. 28 ).

Description of holotype male (MEI 090015).

Length 8.4 mm.

Head. Length 1.06 mm. Ocellar tubercle dark reddish brown, pruinescence gray; slightly raised above level of vertex; setae black, short. Eyes reddish brown, holoptic, ommatidia smaller ventrally and ventrolaterally. Frons pruinescence white, gray dorsally; setae absent; black pruinose band absent lateral to antennal base. Face projecting slightly beyond anterior margin of eyes (0.06 mm). Antenna dark yellow, apex of first flagellomere and all of second and third flagellomeres dark brown, pruinescence silver on scape; antenna/head length 0.61; scape cylindrical, length 0.16 mm, width 0.12 mm, length/width 1.3, scape/pedicel length 1.8, scape/flagellum width 0.75, setae dark brown, short, absent medially, macrosetae dark brown; pedicel globular, length 0.09 mm, length/width 0.7, setae dark brown, short, absent medially; first flagellomere oval, tapered apically to second flagellomere, basodorsal setae dark brown, short, length 0.30 mm, width 0.16 mm, second flagellomere cylindrical, length 0.02 mm, width 0.04 mm, third flagellomere cylindrical, tapered apically, length 0.08 mm, width 0.04 mm, flagellum length 0.40 mm, length/width 2.5, flagellum/scape length 2.5. Parafacial pruinescence white; setae absent. Maxillary palpus cylindrical, apex rounded, reddish brown, pruinescence white; length 0.48 mm, length/width 8.0. Genal setae white, elongate. Occiput convex, dark reddish brown, pruinescence gray; macrosetae dark reddish brown extending as row at lateral end of postocular macrosetae, setae white, elongate becoming sparse dorsally, extending along margin of eye. Postocular macrosetae dark reddish brown, in single row.

Thorax. Macrosetae 3 np, 2 sa, 1 pa, 2 dc, 2 sc. Mesonotum pruinescence silver gray; vittae black, dull with silver gray pruinescence; setae white, elongate intermixed with dark brown setae. Postpronotal lobe concolorous with mesonotum; setae white. Cervical sclerite dark reddish brown, pruinescence white; setae and macrosetae absent. Prosternum with white, elongate setae. Pleuron and scutellum dark reddish brown, pruinescence silver gray; setae white, elongate on propleuron, anepisternum, laterotergite, scutellum, and metanepisternum; absent on proepimeron, anepimeron, katepisternum, meron, and metakatepisternum. Wing. Membrane hyaline, veins pale brown; length 6.0 mm, length/ width 3.3; setulae absent on R 1; pterostigma pale brown, narrow; M 1, M 2, and M 3 originate separately from apex of dc; cell cup closed, petiolate; cell m 3 closed, petiolate; anal angle broadly rounded; alula rounded. Halter dark yellow. Legs. Coxae dark reddish brown, pruinescence white; setae white, elongate; setae absent from posterior half of middle coxa; hind coxa with anterior papillate knob; apical macrosetae dark reddish brown, hindcoxa with one lateral macroseta. Femora dark reddish brown, apex dark yellow, pruinescence white; ventral setae white, elongate on forefemur with white lanceolate, appressed setae on dorsal surface; av 2:0:4, pv 0:2:2. Tibiae dark reddish brown. Tarsi dark reddish brown.

Abdomen. Tergite 1 dark reddish brown medially with broad area of gray pruinescence laterally, separated medially on posterior margin; tergite 2 dark reddish brown becoming dark yellowish brown posteriorly, posterior fourth covered with silver pruinescence that broadens laterally; tergites 3–4 dark yellowish brown, posterior border of silver pruinescence (broader on tergite 3); tergite 5 dark reddish brown with broad posterior border of silver pruinescence; tergite 6 with silver pruinescence (anterior half of tergite retracted under tergite 5); dorsal setae dark reddish brown, appressed on dark reddish brown and dark yellowish brown areas, white, elongate, erect laterally on dorsal surface and appressed across posterior margin; lateral setae white, elongate. Terminalia (MEI 090014). Dark reddish brown. Tergite 8 ( Fig. 22 ) bilobed, anterior margin emarginate; posterior margin deeply emarginate; median length short (0.02 mm) setae dark brown. Sternite 8 ( Fig. 24 ) quadrate, anterior margin and sides rounded; posterior margin broadly emarginate; setae dark brown, scattered, continuous across posterior margin. Epandrium ( Fig. 22 ) quadrate; longer medially than wide; anterior margin slightly emarginate; posterolateral margin short, truncate with slight emargination; lateral view ( Fig. 23 ) quadrate, posterior margin irregular with broad point; setae dark brown. Cercus ( Fig. 22 ) free, oblong; ending distal to posterolateral margin of epandrium; ending slightly basal to apex of hypoproct. Hypoproct ( Fig. 22 ) quadrate, ending distal to posterolateral margin of epandrium; apicoventral area flat; posterior margin slightly emarginate medially, ending distal to apex of cercus. Hypandrium reduced, sclerotized, strap­like, fused to base of gonocoxites. Gonocoxite ventral view ( Fig. 24 ) separated medially, sides rounded, anterior half broad, medial margin rounded with posteromedial margin forming small, angular projection bearing setae, then becoming broadly emarginate and tapering to thick point, apex with small, glabrous, mediolateral, pointed flange, setae dark brown; dorsal view ( Fig. 25 ), inner margin with gonocoxal condostyle, inner gonocoxal process absent; dorsal view ( Fig. 25 ), gonocoxal apodeme short, narrow, not extending beyond anterior margin of gonocoxite, gonocoxal bridge short, emarginate into which fits the lateral margin of basiphallus; lateral view ( Fig. 26 ) oblong, ventral margin rounded, dorsal margin irregular with apical third emarginate and tapering apically to short posterodorsal point; ventral lobe large, rounded apically, curled dorsally around base of gonostylus with short, ventral spines. Gonostylus dorsal view ( Fig. 25 ) narrow, flattened laterally, apical half attenuated with sharp posterolateral projection; lateral view ( Fig. 27 ) basodorsal projection large, rounded, glabrous, ventral margin with basal half projected ventrally, margin rounded, posterior half sinuate with several dark yellow, thick setae. Aedeagus with dorsal apodeme ( Fig. 28 ) quadrate, posterolateral margin rounded, slightly expanded laterally, anterior margin truncate, heavily sclerotized; ventral apodeme ( Fig. 29 ), tapering anteriorly to truncate point, not reaching anterior margin of dorsal apodeme; distiphallus ( Fig. 28 ) tapering apically as narrow, heavily sclerotized ridge with broad posterolateral wing­like flange, posteromedial area deeply concave, lateral view ( Fig. 30 ), posterolateral flange with serrate margin, apical half of distiphallus thick, recurved apically; ejaculatory apodeme ( Fig. 28 ), anterior half expanded laterally in broad, rounded lobe, not reaching anterior margin of dorsal apodeme, anterior margin slightly emarginate, in cross­section flattened dorsoventrally.

Morphometric variation (n=2).

Length 8.2–8.4 mm.

Head. Length 0.96–1.06 mm. Antenna/head length 0.61–0.65; scape length 0.16 mm, width 0.10–0.12 mm, length/width 1.3–1.6, scape/pedicel length 1.8–2.0, scape/flagellum width 0.71–0.75; pedicel length 0.08–0.09 mm, length/width 0.7; flagellum length 0.38– 0.40 mm, width 0.14–0.16 mm, length/width 2.5–2.7, flagellum/scape length 2.4–2.5. Maxillary palpus length 0.42–0.48 mm, length/width 5.3–8.0.

Thorax. Wing. Length 5.8–6.0 mm, length/width 3.2–3.3. Legs. Anteroventral macrosetae 1–2:0:4–5, pv 0:1–2:2.

Female.

Morphometric variation (n=1).

Similar to male except for following.

Body length 7.8 mm.

Head. Length 0.90 mm. Frons pruinescence yellowish brown dorsally, ventral fourth white with large, dark brown, dorsolateral circle, median area dark brown; setae dark brown, short, erect on dorsal three­fourths. Antenna/head length 0.73; scape length 0.20 mm, width 0.11 mm, length/width 1.8, scape/pedicel length 2.5, scape/flagellum width 0.7; pedicel length 0.08 mm, length/width 0.7; flagellum length 0.38 mm, width 0.16 mm, length/width 2.4, flagellum/scape length 1.9. Maxillary palpus length 0.42 mm, length/ width 5.3.

Thorax. Macrosetae 3 np, 2 sa, 1 pa, 2 dc, 2 sc. Wing. Length 5.5 mm, length/width 3.1. Legs. Femora dark reddish brown, apex dark yellow, pruinescence white; setae white, elongate ventrally on forefemur; av 0:?:4, pv 0:?:2.

Abdomen. Tergite 1 dark brown on anterior half, black posteriorly; tergites 2–5 dark brown medially becoming black laterally, posterior margin whitish gray; tergites 7–8 dark brown anteriorly, dark yellow posteriorly; dorsal setae dark brown, appressed, white, appressed across posterior margin of tergites 1–4; lateral setae white on tergites 1–3, dark brown on remaining tergites. Terminalia (MEI 048047). Anterior margin of sternite 8 truncate; aedeagal guide absent. Setae on median lobe of tergite 9 dark reddish brown. Furca ( Fig. 31 ) oblong, anterior margin lightly sclerotized, length 0.50 mm, width 0.30 mm; closed anteriorly and posteriorly; anteromedial, anterolateral, posteromedial, posterolateral projections absent, common spermathecal duct shorter than furca. Spermathecal ducts expanded posteriorly before becoming thread­like anteriorly and ending in 2 spherical spermathecae.

Immature Stages. Unknown.

Habitats and Temporal Phenology. Ptilotophallos megasathe has been collected in October.

Distribution. Ptilotophallos megasathe is known only from Brazil.

Specimen examined. Type specimen. The holotype male of Ptilotophallos megasathe Webb is labeled " BRAZIL, Rondonia, 7 km E Costa Marques, 03–11 OCT 1987, T. KLEIN " ( MEI 090015 ) and is deposited in the USNM . PARATYPES. Same data as holotype, 1 male MEI 048097 ( INHS), 1 female 090014 ( USNM) .

Figures

FIGURES 22–31. Ptilotophallos megasathe 22. Tergite 8, epandrium, cerci, hypoproct, dorsal view. 23. Epandrium, lateral view. 24. Sternite 8, hypandrium, gonocoxite, ventral view. 25. Gonocoxite, hypandrium, dorsal view. 26. Gonocoxite lateral view. 27. Gonostylus, lateral view. 28. Aedeagus, dorsal view (insert: frontal view). 29. Aedeagus, ventral view. 30. Aedeagus, left lateral view. 31. Female internal reproductive organs. Scale = 0.1