Stenogephyra namibiensis, Webb, Donald W. & Hauser, Martin, 2011

Webb, Donald W. & Hauser, Martin, 2011, Revision of the genus Stenogephyra Lyneborg (Diptera: Therevidae: Phycinae), Zootaxa 2837, pp. 67-85 : 77-79

Stenogephyra namibiensis spec. nov.

( Figs. 8–9 , 28–31, 45)

Etymology. ensis (Latin) = a suffix denoting place, locality, country. This name is used as a noun in apposition and refers to the Namib desert of Namibia.

Diagnosis. Stenogephyra namibiensis spec. nov. is similar to S. janiceae spec. nov., S. schlingeri spec. nov. and S. torrida in possessing silver pubescence on gena (lateral view) restricted to band along posterior margin of eye, ending at lower eye margin ( Figs. 4, 8, 12, 14 ); one pair of dorsocentral macrosetae, and in having vein M2 short, not reaching the hind margin of the wing ( Lyneborg 1987, Fig. 6 ). Stenogephyra namibiensis spec. nov. differs from S. torrida in having the legs dark brown (mid– and hindfemur occasionally dark yellowish brown). It differs from S. schlingeri spec. nov. in having silver pubescence on frons more developed, forming two connected markings and often reaching below lower eye margin ( Fig. 8 ); lower face with central hemispherical bulge and laterally the gena and lower frons forming another bulge separated from central bulge by deep furrow, creating impression of a “nose” ( Figs. 5, 9, 15 ); and three pairs of notopleural macrosetae. It differs from S. janiceae spec. nov. and S. torrida in having the silver pubescence stripe on face reaching ventral margin of face ( Fig. 8 ); silver pubescence on frons present between median ocellus and eye margin and also forming a complete band posteriorly on occiput behind ocellar tubercle ( Fig. 8 ); halter knob completely white.

Description of male. Variation (n=10). Body length 3.3–4.8, 4.1 mm. Head. Length 0.46–0.70, 0.58 mm. Eyes separated by distance over two times width of ocellar tubercle. Frons ( Fig. 8 ) dark reddish brown, glossy with broad band of silver pubescence across area of ocellar tubercle and lateral and dorsolateral to antennal base; setae black, elongate. Antenna dark reddish brown, pubescence light gray; antenna/head length 1.9–2.4, 2.1; scape length 0.09–0.18, 0.14 mm, width 0.10–0.16, 0.11 mm, length/width 0.9–1.5, 1.2, scape/pedicel length 1.5–2.8, 2.1, scape/flagellum width 0.6–0.9, 0.7, setae dark brown; pedicel length 0.05–0.08, 0.07 mm, width 0.08–0.14, 0.10 mm, length/width 0.4–1.0, 0.7, setae dark brown, short; flagellum length 0.85–1.10, 1.01 mm, width 0.14–0.20, 0.16 mm, length/width 5.8–7.9, 6.3, flagellum/scape length 6.1–9.4, 7.5. Parafacial ( Fig. 8 ) expanded, bulbous, dark reddish brown, glossy with broad area of silver pubescence; setae black, elongate. Maxillary palpus brown; length 0.22–0.44, 0.27 mm, width 0.05–0.06, 0.06 mm, length/width 3.0–7.3, 4.6; setae brown, elongate. Gena ( Figs. 8–9 ) rounded, dark reddish brown, glossy; setae white, elongate. Occiput ( Figs. 8–9 ) dark reddish brown, glossy with silver pubescence along posterior margin of eye and across vertex; setae white becoming dark brown dorsally. Thorax. Macrosetae 3 np, 1 dc. Mesonotum dark reddish brown, pubescence gray, dorsocentral and dorsolateral vittae separated by dense line of gray pubescence; setae black, short. Pleuron dark reddish brown, glossy, pubescence gray on dorsal half of anepisternum, over entire meron; setae pale brown on anepisternum (across dorsal margin) and laterotergite, dark brown on scutellum. Wing. Membrane pale gray; length 2.4–3.5, 3.0 mm, width 0.8–1.2, 1.0 mm, length/width 2.5–3.5, 3.0. M1 and M2 originate separately from discal cell, M2 not reaching wing margin. Halter stalk dark brown, knob pale yellow. Legs. Coxae dark reddish brown, pubescence gray; setae yellow. Fore femur dark brown, mid– and hind femur dark yellowish brown. Fore tibiae dark brown, mid– and hind tibia dark yellowish brown. Tarsi dark brown. Abdomen. Dark reddish brown, glossy, tergites 1–2 with posterior area orange brown; dorsal and lateral setae white to pale yellow. Terminalia (MEI 148460). Dark brown. Sternite 8 (Fig. 28) quadrate, posterior margin broadly rounded; setae dark brown, continuous across posterior margin. Gonocoxite ventral view (Fig. 28), posterior margin sinuate then extending posterolaterally to pointed projection, setae dark brown. Aedeagus lateral view (Fig. 29) thick, apex short, sinuate; ejaculatory apodeme lateral view (Fig. 29) pale brown, anterior margin paler, anterior half clavate.

Female. Similar to male except for following. Variation (n=10). Body length 3.6–6.1, 5.2 mm. Head. Length 0.50–0.80, 0.68 mm. Antenna/head length 1.24–1.84, 1.52; scape length 0.16–0.28, 0.21 mm, width 0.09–0.12, 0.10 mm, length/width 1.3–2.8, 2.1, scape/pedicel length 2.0–3.5, 2.6, scape/flagellum width 0.6–1.2, 0.8; pedicel length 0.06–0.10, 0.08 mm, width 0.10–0.11, 0.10 mm, length/width 0.6–1.0, 0.8; flagellum length 0.62–0.78, 0.73 mm, width 0.10–0.16, 0.13 mm, length/width 4.5–7.0, 5.8, flagellum/scape length 2.8–4.4, 3.6. Maxillary palpus length 0.18–0.38, 0.27 mm, width 0.06–0.08, 0.06 mm, length/width 3.0–6.3, 4.3. Thorax. Macrosetae 3 np, 1 dc. Wing. Length 3.0–4.5, 4.1 mm, width 1.0–1.5, 1.4 mm, length/width 2.8–3.3, 2.6. Abdomen. Terminalia (MEI 170272). Sternite 8 (Fig. 30) broad, sides and anterior margin rounded. Furca (Fig. 31) oval, densely membranous with large median opening and posterolateral margins sclerotized; length 0.40 mm, width 0.23 mm.

Distribution. Stenogephyra namibiensis spec. nov. is known from Namibia (Fig. 45).

Habitats and Phenology. Stenogephyra namibiensis spec. nov. has been handnetted on Salvadora persica L. and collected in Malaise traps in riparian and riverine vegetation. Irwin (2001: Figs. 6–7 , as S. torrida ) showed the seasonal periodicity of males and females of S. namibiaensis spec. nov. emerging along the Kuiseb River, Gobabeb. Adults have been collected throughout the year ( Irwin 2001: Figs. 6–7 )

Specimens examined (n = 130). Type specimens. The holotype male of Stenogephyra namibiensis spec. nov. (MEI 148874) is labeled " NAMIBIA, Namib-Naukluft Park, Namib Desert Res. Stn., Kuiseb River, malaise in riparian vegetation, 420m, 21/ 28-IV-1997; I Kapofi, Irwin, ME, 23˚33’45”S, 15˚02’38”E"and is deposited in SMWN. PARATYPES. NAMIBIA. Gobabeb, Kuiseb River [-23.549, 15.031], 400m, 12.II.1974, Irwin, M.E., Irwin, B.J., 8Ψ MEI 084320–2, 084324–8 (MEIC), riverine forest and sand; Namib-Naukluft Park, Namib Desert Research Station, Kuiseb River [-23.563, 15.044], 420m, 22.XI.1996, Irwin, M.E., 9ɗ MEI 116566 (CSCA), 116567 (NMSA), 1165668 (SAMC), 116669–74 (MEIC), 25Ψ 116579 (CSCA), 116582 (NMSA), 116583 (SAMC), 116584–7, 116593–604, 116607–11, 170272 (MEIC), Malaise trap, riverine vegetation; 23.XI.1996, 12ɗ MEI 116554–7, 116559–64, 116578, 170273, 7Ψ 0 89477, 116588–92, 170271 (INHS), Malaise trap, riverine vegetation; 8–15.I.1997, Kapofi, I., Irwin, M.E., 6ɗ 148845–50, 9Ψ 148853–61 (MEIC), Malaise trap, in riparian vegetation; 5–14.III.1997, 5ɗ 125167–71, 1Ψ 125165 (MEIC), Malaise trap, in riparian vegetation; 21–28.IV.1997, 25ɗ 148843–4, 148851–2, 148863–73, 148875–84 (MEIC), Malaise trap, in riparian vegetation; 7–13.X.1997, 1ɗ 125173, Malaise trap, in riparian vegetation (MEIC); near Gobabeb, Kuiseb River [-23.34, 15.03], 10– 16.VII.1984, Kuiseb Survey, 3ɗ 122685 –6, (SMWN) Malaise trap, 122677 (SMWN) from Salvadora persica L.; 18–20.III.1983, 11ɗ 122671 –4, 122677 –9, 122681 –4 (SMWN), Malaise trap; Oase, at Gaub River [-23.487, 15.769], 730m, 22.XI.1996, Irwin, M.E., 4ɗ MEI 116558, 116575–7, 1Ψ 116612 (MEIC), Malaise trap, riverine vegetation.

Lyneborg (1987) also cited S. namibiensis spec. nov. (as S. torrida ) from the mouth of the Swakop River [- 22.683, 14.533] and 5 km E. Swakopmund [-22.683, 14.623].

Figures

FIGURES 2 – 15. Stenogephyra sp. nov. 2 – 3. S. dianeae spec. nov.. 2. Head frontal view. 3. Head lateral view. 4 – 5. S. janiceae spec. nov.. 4. Head frontal view. 5. Head lateral view. 6 – 7. S. minuta. 6. Head frontal view. 7. Head lateral view. 8 – 9. S. namibiensis spec. nov.. 8. Head frontal view. 9. Head lateral view. 10 – 11. S. parkeri spec. nov. 10. Head frontal view. 11. Head lateral view. 12 – 13. S. schlingeri spec. nov. 12. Head frontal view. 13. Head lateral view. 14 – 15. S. torrida. 14. Head frontal view. 15. Head lateral view.