Austrosetia semirufa Felder & Felder, 1874

Bartsch, Daniel, 2013, Revisionary checklist of the Southern African Sesiini (Lepidoptera: Sesiidae) with description of new species, Zootaxa 3741 (1), pp. 1-54 : 17-18

Austrosetia semirufa Felder & Felder, 1874

Figs 34–36 , 37–42 , 73–74 , 87 , 95 , 102 , 115 , 126 .

Literature. Felder & Felder 1874: 2, pl. 82, fig. 22 ( Fig. 36 ); Hampson 1919: 60 ( Synanthedon ); Dalla Torre & Strand 1925: 44 ( Synanthedon ); Gaede 1929: 521 ( Synanthedon ); Heppner & Duckworth 1981: 33 ( Synanthedon ); Pühringer & Kallies 2004: 43 ( Austrosetia ).

Specimens examined. Lectotype: ♀ ( Fig. 35 ), South Africa, Cape Town , January 1862, Wynberg leg. ( BMNH), designated here.

Paralectotype: 1 ♀ ( Fig. 34 ), South Africa, Knysna, R. Trimen leg. (= paratype of Alonina rufa new sp.) ( BMNH) .

Additional specimens: 52 ♂ ( Figs 37–39 , 73 ), 49 ♀ ( Figs 40–42 , 74 ), South Africa, Eastern Cape Province, 50 km W Graaf-Reinet, E Mt. Torberg , 32°10’ S, 23°23’ E, 1550 m, larva 22.–23.Nov.2007, adults emerged Dec.2007 – Feb.2008, D. Bartsch leg. (♀ gen. prep. Bartsch 2008 –9, Fig. 126 ; ♂ 2008–10, Fig. 115 , wing venation ( Fig. 87 ), antenna ( Figs 95 , 102 ); ♂ 2008–11; ♀ 2010–23) ( SMNS, TMPS) ; 1 ♀ “Capetown, C.G.H. 9.Dec.[19]00” ( TMPS) .

Very little relevant information to A. semirufa was given in the original description. Two historical specimens are kept in the BMNH. Both are females, not males as originally stated, and both are badly damaged and lack parts of the antennae, labial palpi, legs and wings. The left forewings are broken off and the first specimen was repaired with that of the second one, whereas the second one has a forewing of an undetermined species of Melittia Hübner, [1819] . The specimens are labelled: (1) “type”, “ Cape Town, Jan. 1862, Wynberg”, “ Austrosetia semirufa Abb [?] in tab.“; (2) “(Knysna). S. Africa.”, “rare. R. Trimen”, “Felder colln.”, “ Synanthedon semirufa Feld. , l[eft] F[ore] W[ing] stuck on [handwritten by Hampson]”. The label data of the first specimen do not agree with that of the original description, which is given in the explanation of the plates: “ ♂, ( Sesia ) Africa mer. Knysna (Jan. Trimen)”. However, only this specimen from Cape Town does agree with the one originally figured ( Fig. 36 ). The second specimen, whose labels agree with the original data, appears very different. As there is no clear information about the number of types and as the reason for the confusion of the collecting localities cannot be resolved any longer, both specimens are here considered to be primary types. According to ICZN recommendation 74B, the first specimen from Cape Town is here selected as the lectotype. The second one from Knysna is the paralectotype. This specimen belongs to Alonina rufa new sp., which is described above.

Description of the male ( Figs 37–39 , 73 ). Medium sized, wingspan 19–24 mm, forewing length 8.5–10.5 mm, antenna 6.0–7.5 mm, body 11–15 mm. Head with haustellum strongly reduced, not visible; labial palpus rough, whitish, ventrally sparsely and laterally densely interspersed with black and white, hair-like scales, laterally with indistinct black stripe; first and third palpomere laterally with a few orange scales; frons with several hair-like scales, medially creamy-grey, laterally pure white; vertex mixed grey and black; pericephalic scales creamy-grey, dorsally mixed with dark grey, hair-like scales, laterally white; antenna black, bipectinate, rami very long, but in dried specimens extremely adpressed and hardly discernible, distally tapering, covered with macroscopic hairs; scapus with mixed creamy-grey and black, hair-like scales. Thorax black, densely covered with grey, hair-like scales; inner margin of tegula narrow grey. Abdomen with tergites predominantly black, posterior half of tergites 4–7 brownish-grey, tergites 4, 6 and 7 with narrow, white posterior margins; tergites 1–3 with dense grey, hair-like scales, posteriorly some brownish-grey scales; sternites light grey; anal tuft black, dorso-proximally and ventrally interspersed with brownish-grey. Legs mixed light grey and black; coxa white, mottled with black; coxa, femur, tibia and first tarsomere of hind leg with rather long, white, hair-like scales; hind tibia medially with white, ventrolateral patch and dorsally with mixed light grey and black, hair-like scales; spurs white, laterally grey. Forewing covered with a mixture of black and brownish-grey scales; discal spot narrow, black; transparent areas and apical area well developed, the latter with sub-distal row of greyish patches between veins; longitudinal transparent area extends to discal spot; anterior transparent area short, medially with longitudinal black scale line; external transparent area trapezoid, usually divided into five, occasionally into four parts, somewhat broader than apical area, broadest at tornus. Hindwing with veins, margins and discal spot black. Fringes dark grey, white at anal angle.

Redescription of the female ( Figs 40–42 , 74 ). Distinctly different from male; larger, with wingspan 22–30 mm, forewing length 9.5–13.5 mm, antenna 5.5–7.0 mm and body 14–18 mm. Head with labial palpus dorsally smooth, ventrally rough, almost white with orange tinge, laterally and ventrally with some light orange and black scales, third palpomere light orange throughout; frons rough, medially white with orange tinge; laterally smooth and pure white; vertex and pericephalic scales orange-brown, mixed with black, hair-like scales; antenna clavate, black; scapus with dense black, hair-like scales. Thorax almost black, dorsally indistinctly interspersed with dark orange-brown, except for three longitudinal black lines; prothorax laterally with a narrow, yellow-white stripe. Abdomen and anal tuft black; tergites 1–3 with black, hair-like scales; tergites 4 and 6 with small white posterior margin. Legs black; fore coxa white, -femur and -tibia ventrally white with some pale orange scales; mid- and hind leg with coxa distally narrowly framed white, femur disto-laterally and tibia medio-laterally white. Forewing black, cubitus stem and anal margin covered with some brownish-grey scales, position of transparent areas more or less orange, distal of discal spot a small tripartite orange patch; hindwing orange, outer veins and margins brownishblack; fringes dark greyish-black; underside of all wings orange, forewing basally and at costal margin yellowishgrey.

Genitalia ( Figs 115 , 126 ). See genus description.

Variation. The orange colour of the female hindwing varies considerable in extension and brilliance and is often more or less covered with brownish-black distally, to the extreme of entirely dark brown in two specimens.

Diagnosis. The males are somewhat similar to that of Felderiola candescens and F. karooensis , but differ by the lack of a pink tinge and by the bi- not unilaterally pectinate antennae with extraordinary long rami. The female is unmistakable by its orange hindwing. See also diagnosis of Anaudia felderi .

Bionomics and habitat. Through the field work of the author the life history of this species has been discovered and an extensive series of both sexes was reared from larvae. Fontain-bos Psoralea glabra (= P. pinnata ssp. glabra ) ( Fabaceae ) is the host plant. It is an erect shrub or small tree up to rarely 4 m in height, which occurs “along streams, fringing vleis and forests and at mountain slopes” ( Palgrave 1977). The larva or very often several larvae together, construct a short tunnel near ground level in the trunk or in the upper part of the root, occasionally in the base of a stem. Sometimes their presence is indicated by dried or wilted stems. When fully grown the larva forms a straight, silk-lined tunnel in the trunk, closed by a thin lid of bark or constructs a short exit tube from sawdust and silk. Adults hatch during the morning hours, in culture from late November to January. Males were not attracted to artificial pheromones used in the field. A single female was found resting during the early evening hours at a height of more than one meter on the top of the host.

Figures

FIGURES 25–36. Specimens of Alonina Walker, 1856; Anaudia Wallengren, 1863 and Austrosetia Felder & Felder, 1874: 25– 27. Alonina fusca new sp. (25–26) ♂ holotype; (27) ♀ paratype. 28–32. Anaudia felderi Wallengren, 1863, (28–29) ♂, pale specimen, Northern Cape, Kalahari, ca. 50 km E Hotazel, Tswalu Resort; (30) ♂, dark specimen, ibid.; (31) ♀ syntype; (32) ♀, Tswalu Resort. 33. Anaudia thyranthrena new sp., ♂ holotype. 34 Alonina rufa new sp., ♀, paratype, Knysna (paralectotype of Austrosetia semirufa Felder & Felder, 1874). 35–36. Austrosetia semirufa Felder & Felder, 1874: (35) ♀ lectotype; (36) ♀, original figure.

FIGURES 37–48. Specimens of Austrosetia Felder & Felder, 1874 and Felderiola Naumann, 1971: 37–42. Austrosetia semirufa Felder & Felder, 1874, Eastern Cape Province, 50 km W Graaf-Reinet, E Mt. Torberg, (37–38) ♂, specimen with large transparent areas; (39) ♂, specimen with small transparent areas; (40–41) ♀, orange specimen; (42) ♀, dark specimen. 43–48. Felderiola candescens (Felder & Felder, 1874), (43–44) ♂, Orange Free State Province, Bethlehem; (45) ♀ syntype; (46–47) ♀, yellow form, ibid.; (48) ♀, dark form, ibid. (photo Tosevskii, without scale bar).

FIGURES 73–78. Living specimens and life-history: 73–74. Austrosetia semirufa Felder & Felder, 1874, Eastern Cape Province, 50 km W Graaf-Reinet, E Mt. Torberg, (73) ♂; (74) ♀. 75–78. Anaudia felderi Wallengren, 1863, Northern Cape, Kalahari, ca. 50 km E Hotazel, Tswalu Resort, (75) ♀, pale specimen showing resting position; (76) exit-tubes with dead pupa and exuvia; (77) root stock of the host plant with exit tubes showing presence of larvae/pupae; (78) host plant Sutherlandia frutescens (Fabaceae).

FIGURES 84–91. Wing venations: (84) Cicinnoscelis longipes Holland, 1893; (85) Alonina rygchiiformis Walker, 1856; (86) Anaudia felderi Wallengren, 1863, syntype; (87) Austrosetia semirufa Felder & Felder, 1874; (88) Felderiola candescens (Felder & Felder, 1874); (89) Monopetalotaxis doleriformis (Walker, 1856); (90) Hagnogyna sanguicosta (Hampson, 1919); (91) Vespanthedon cerceris Le Cerf, 1917, holotype.

FIGURES 92–98. Male antennae: (92) Alonina pyrocraspis (Hampson, 1910); (93) Alonina rygchiiformis Walker, 1856; (94) Anaudia felderi Wallengren, 1863; (95) Austrosetia semirufa Felder & Felder, 1874; (96) Felderiola candescens (Felder & Felder, 1874); (97) Monopetalotaxis doleriformis (Walker, 1856); (98) Hagnogyna bartschi (Freina, 2011).

FIGURES 99–106. Scanning electron microscope pictures of antennae: (99) Cicinnoscelis flavipes new sp., #f holotype; (100) Alonina rygchiiformis Walker, 1856; (101) Anaudia felderi Wallengren, 1863; (102) Austrosetia semirufa Felder & Felder, 1874; (103) Felderiola karooensis new sp.; (104) Monopetalotaxis doleriformis (Walker, 1856); (105) Hagnogyna bartschi (Freina, 2011); (106) Sesia bembeciformis (Hübner, 1803).

FIGURES 115–116. Male genitalia: (115) Austrosetia semirufa Felder & Felder, 1874; (116) Vespanthedon cerceris Le Cerf, 1917, holotype.

FIGURES 124–126. Female genitalia of Anaudia Walker, 1856 and Austrosetia Felder & Felder, 1874: (124–125) Anaudia felderi Wallengren, 1863 (124 syntype); (126) Austrosetia semirufa Felder & Felder, 1874.