Prosoeca peringueyi Lichtwardt, 1920

Theron, Genevieve L., Ellis, Allan G. & Midgley, John M., 2025, A revision of a spring-active clade of Prosoeca Schiner, 1867 (Diptera, Nemestrinidae), keystone pollinators from the Greater Cape Floristic Region in South Africa, with descriptions of three new species, ZooKeys 1257, pp. 249-284 : 249-284

publication ID	https://doi.org/10.3897/zookeys.1257.155954
publication LSID	lsid:zoobank.org:pub:7D8BD25C-6BBF-44AE-8E5F-0B055043E470
DOI	https://doi.org/10.5281/zenodo.17488908
persistent identifier	https://treatment.plazi.org/id/71AC49E3-AC9E-5ECC-8FB3-9F6EB01F0FFB
treatment provided by	ZooKeys by Pensoft
scientific name	Prosoeca peringueyi Lichtwardt, 1920
status

Treatment

Prosoeca peringueyi Lichtwardt, 1920 View in CoL

Figs 1 View Figure 1 , 2 D View Figure 2 , 3 C View Figure 3 , 4 C View Figure 4 , 5 C View Figure 5 , 6 C View Figure 6 , 7 E, F View Figure 7

Prosoeca peringueyi Lichtwardt, 1920: 98; Bezzi 1924: 175; Bernardi 1973: 258; Bowden 1980: 375; Barraclough 2006: 49. View in CoL

Type material examined.

Lectotype: South Africa: • 1 ♂ Northern Cape, Ookiep, Namaqua Div ; R. Lightfoot leg.; Sep. 1990; SAM-DIP-A 009013 ; SAMC . This specimen is hereby designated as lectotype. Paralectotype: South Africa • 1 ♀ Northern Cape, Namaqualand, Klipfontein , Aug. 1890; R. M. Lightfoot; SAM-DIP A 009009 ; SAMC . This specimen is hereby designated as paralectotype.

Other material examined.

South Africa: • 1 ♂ 1 ♀, Northern Cape: Van Rhynsdorp; 28 Jul. 1927; Dr. Brauns leg.; Lapeirousia fissifolia , [illegible]; NMSA -DIP 49945 , NMSA -DIP 049943 ; NMSA . • 2 ♂♂ 1 ♀ Western Cape: Clanwilliam district: Pakhuis Pass ; 950 m; 17–19 Oct. 1964; B & P Stuckenberg leg.; NMSA -DIP 052845 , NMSA -DIP 76251 , NMSA -DIP 76252 ; NMSA . • 1 ♀ Western Cape: Pakhuis Mts: Pakhuis Farm 2 miles NNE ; 14 Sep. 1972; Irwin M. E., Irwin B. J. leg.; NMSA -DIP 054873 ; NMSA . • 1 ♂ Western Cape: Vanrhynsdorp: Gifberge ; Sep. 1911; NMSA -DIP 055007 ; NMSA . • 1 ♀ Northern Cape: 5 km N of Komaggas ; 29°45'S, 17°31'E; 390 m; # 85; 24 Aug. 1995; J & A Londt leg.; Rocky slope; Macchia; NMSA -DIP 50895 ; NMSA GoogleMaps . • 5 ♀♀ Western Cape: Clanwilliam ; Sep. 1928; Dr. Brauns leg.; NMSA -DIP 76253 –76255, NMSA -DIP 76248 , NMSA -DIP 76249 ; NMSA. • 1 ♂ Western Cape: Clanwilliam; Dr. Brauns leg.; Sep. 1928; NMSA -DIP 76250 ; NMSA . • 2 ♀♀ Western Cape Vanrynsdorp ; Jul. - Aug. 1927; G. v. Son leg.; NMSA -DIP 52017 , NMSA -DIP 51796 ; NMSA . • 1 ♂ Western Cape: Clanwilliam: Karroo-berg ; G. van Son leg.; 9 Aug. 1927; NMSA -DIP 51950 ; NMSA . • 1 ♀ Northern Cape: Studers Pass road: NE of Garies ; Late Aug. - early Sep. 2005; sweep-net; G. B. P. Davies leg.; NMSA -DIP 078933 ; NMSA . • 1 ♂ 1 ♀ Western Cape: Clanwilliam area: Cederberg mnts: Pakhuis Pass: Kleinkliphuis Farm ; G. B. P. Davies leg.; NMSA -DIP 078929 , NMSA -DIP 078930 ; NMSA . • 4 ♂♂ 1 ♀ Northern Cape: Nama Khoi: Naries ; 29.701°S, 17.665°E; 5 Aug. 2007; T. van der Niet leg.; NMSA -DIP 219356 – 219359, NMSA -DIP 219355 ; NMSA GoogleMaps . • 1 ♀ Western Cape Province: Clanwilliam Dam: E bank ; 23 Sep. 1996; F. W., S. K. & R. W. Gess leg.; 96 / 97 / 209, on purple fls, Lapeirousia sp. Iridaceae ; AMGS -ENT 101701 ; AMGS . • 1 ♂ Western Cape: Vanryansdorp: Gifberg ; 1 Sep. 1911; SAM-DIP A 009010 ; SAMC . • 1 ♂ 1 ♀ Western Cape: Clanwilliam: Pakhuis pass ; 1 Sep. 1942; South African Museum Expedition leg.; SAM-DIP A 009008 ; SAMC . • 1 ♀ Northern Cape: Namaqualand: Bowesdorp ; SA Museum leg.; SAM-DIP A 009011 ; SAMC . • 2 ♀♀ Northern Cape: Namaqualand; 2917 D 8; Hester Malan N. R. ; M. Struck leg.; 13 Sep. 1986; SAM-DIP A 012367 , SAM-DIP A 009007 ; SAMC . • 1 ♀ Northern Cape: Soebatsfontein turnoff from N 7; 3017 BB ; 6 Sep. 1986; K. Steiner leg.; 1428; Babiana ; SAM-DIP A 012381 ; SAMC . • 1 ♀ Western Cape: Clanwilliam: Ramskop Camp ; - 32.18, 18.88; K Steiner leg.; 1736; 21 Aug. 1984; Lapeirousia jacquinii ; SAM-DIP A 012382 ; SAMC . • 2 ♂♂ Northern Cape: 12 km N of Steinkopf ; 2917 BB; 4 Aug. 1988; K. Steiner leg.; Sutera fruticosa ; SAM-DIP A 012386 ; SAMC . • 1 ♀ Western Cape: Clanwilliam: Ramskop ; Macpherson leg.; 22 Aug. 1984; Laperiousia jaquenii; SAM-DIP A 009012 ; SAMC . • 1 ♂ Western Cape: 10 km W. Algeria, Clanwilliam road , 32.21°S, 19.03°E; 4 Sep. 1987; C. D. Eardley leg.; SANC GoogleMaps .

Diagnosis.

Large-sized (length 13–21 mm), grey body with intricate patterning on the thorax and the abdomen, thorax with two dark black sub-lateral vittae extending to the transverse suture, legs dark brown, proboscis length 1.55 ± 0.02 × the length of the body (range of un-extended proboscis length 23–35 mm), wings with smoky brown patterned infuscation on the anterior 1 / 2 of the wing and cross-vein between R 4 & R 2 + 3 complete in specimens from the northern part of the range (north of Calvinia). Prosoeca peringueyi , P. marinusi , and P. torquata can be distinguished from all other species in the clade by their proboscis which is longer than the length of their bodies, in contrast to P. ora sp. nov., P. aquilo sp. nov., and P. parva sp. nov. that have a proboscis shorter than the length of their body. Prosoeca peringueyi and P. torquata have a dark smoky brown wing patterning that is strikingly distinct from the almost hyaline posterior wing membrane, while P. marinusi has a paler brown wing patterning that is never strikingly distinct from the lightly infuscated posterior wing membrane (Fig. 5 A – C View Figure 5 ). Prosoeca peringueyi differs most noticeably from P. torquata and P. marinusi , by the presence of two dark black sublateral vittae on the anterior of the thorax. Additionally, P. peringueyi has a generally paler thorax than P. torquata or P. marinusi .

Redescription.

Male. Body length: mean 18.1 mm ( n = 43); range 13–21 mm. Intertegular width: mean 7.0 mm; range 5–8 mm ( n = 11). Proboscis length: mean 29.2 mm; range 23–35 mm ( n = 29). Wing length: mean 19.6 mm; range 18–21 mm ( n = 19).

Head. (Figs 4 C View Figure 4 , 6 C View Figure 6 ) Ground colour generally red-brown to dark brown. Ocellar tubercle somewhat bulbous and developed, just evident above upper eye margin in profile, with dense silvery pruinescence; width between eyes at the anterior ocellus 3.9–4.2 × the length of the anterior ocellus; anterior ocellus separated from posterior ocelli by shallow transverse groove; pile generally long, black. Frons trapezoid; width anterior to ocellar tubercle 0.7 × the width above antennal insertions; slightly to moderately swollen between antennal insertions and anterior ocellus; swelling recedes strongly towards eye margin; pruinescence relatively dense, brownish; pile generally absent. Antenna with scape 1.5–2 × length of pedicel; first flagellomere subequal to the length of scape + pedicel; style longer than scape + pedicel + flagellomere 1; ground colour transitioning to a darker hue, on the proximal side of the first flagellomere, style darker than remainder of antenna; scape, pedicel and flagellomere 1 with irregular silver to brown pruinescence; pedicel with both elongate and short pile, black and white pile, flagellomere 1 with short black pile basally on the dorsal side. Facial area bulbous in profile, with horizontal groove present; sublaterally irregular yellow-brown; with silver to brown pruinescence, but pruinescence largely absent from medial section of face; pile mostly white, elongate, sparse, more dense than on frons. Gena with pile a mixture of black and white to pale yellow, elongate, and dense, forming the beard. Proboscis 1.2–1.7 × the length of the body, black with dorsal part of basal 1 / 3–1 / 2 brown. Palpus with first segment significantly longer than that of second segment, second segment much narrower than first segment; colour generally dark brown to black; pile longer on the first segment.

Thorax (Fig. 3 C View Figure 3 ). Scutum dark grey to black; pruinescence mostly silver and brown, with pale grey to silvery pruinescence complete along the lateral sides of the scutum, joining on scutellum; median and paired sublateral vittae evident; medial vitta narrow anteriorly, widening towards scutellum; paired sublateral vittae distinct black, straight, ending at transverse suture; pruinescence forming irregular pattern; pile mostly black, sparse, shorter than the pile on the posterior of the scutellum; pile on postpronotal lobe and anterodorsal region of scutum white, sparse; postalar callus with black pile dorsally, ventral side with a tuft of white pile. Scutellum with distinct central dot, or central diamond shaped marking; anterior margin covered by silver to brown pruinescence; posterior margin with a dark, black border; pile on disc of scutellum black, relatively long, sparse compared to scutum; pile along posterior margin elongate, mostly black, dense compared to disc of scutellum; with some pale yellow to golden pile laterally (sometimes closer to white). Pleuron mostly blackish; with silver pruinescence, sparser than on scutum; pile generally a mixture of black and white to yellow, relatively long, of intermediate density; most dense and elongate in two tufts, ventral and anterior to the base of the wing and between postalar callus and posterior spiracle; tuft of pile anterior to wing base directed posteriorly, mostly white to golden with some black pile; tuft of pile on katatergite directed posteriorly, black and golden; katepimeron with pile absent, or sparse elongate white pile. Legs. Coxae red-brown to dark brown; with pile mostly off-white to golden, elongate, dense. Trochanters mostly blackish, with some yellow-brown colouring; pile short, very sparse. Femora red-brown to dark brown, with dark marking on dorsal side of the distal end present; pile mostly black, mostly short, dense, but with elongate pile dorsally on proximal 1 / 3 – 1 / 2; ventral pile typically longer, sparse; hind femur with short pile more evenly distributed than on fore and mid femora. Tibiae red-brown to black; with mostly short pile, most dense on hind tibia. Tarsi red-brown to dark brown, hind tarsi tend to be darker. Wings (Fig. 5 C View Figure 5 ). Shape relatively slender; broadest just basal to termination of CuP on posterior margin; alula broad; costal margin close to straight, without distinct anteriorly curved flexure; Sc termination on C aligned with termination of M 4 on posterior margin of wing; R 1 terminated closer to R 2 + 3 than to Sc; insertions of Sc and R 1 well separated; cross vein between M 1 and M 2 absent; cross vein between R 4 and R 2 + 3 just beyond fork of R 4 and R 5 present, or absent; R 1 relatively straight; R 4 deep bowing upward; R 5 shallow bowing upward; M 1 and M 2 slightly curved upward; cell cua open at margin; CuA and CuP well separated. Dark marking on R 1 positioned just basal to humeral cross vein; membrane with smoky brown infuscation; appearing darker on anterior 1 / 2–1 / 3 of wing; posterior region of wing almost hyaline; isolated darker patches distinct in hyaline region; the distinction between brown infuscation and hyaline membrane sharply delineated. Tuft of pile on base of wing white. Haltere with pale brown to yellow stalk; bulb dark brown.

Abdomen (Fig. 3 C View Figure 3 ). Colour of abdomen generally red-brown; T 2 with posterior margin stout and relatively broad; abdomen tapering abruptly after T 3. Tergites with silvery pruinescence; membrane between T 1 and T 2 with silvery to brown pruinescence; medial brown pruinescent vitta distinct, extending from the posterior margin of T 1 to terminalia, usually not covering the full length of each tergite; paired sublateral markings of indistinct shape, on T 2 – T 4. Pile on tergites mostly black, both long and short, of intermediate density; along anterior margins of T 2 white to pale yellow, elongate, sparse; posterolateral pile on T 2 – T 4 black, elongate, dense; T 5 with pile along lateral margins more evenly distributed than that of T 2 – T 4. Sternites typically paler than tergites; pale reddish brown; pruinescence silver with medial brown vittae, relatively sparse. Sternites with pile a mixture of black and white, mostly short, sparse; pile on S 1 – S 3 intermixed, long, white; membrane adjacent to lateral margins of S 2 – S 4 typically with profuse, decumbent, elongate, white pile.

Genitalia (Fig. 7 E, F View Figure 7 ). Hypandrium triangular in shape; relatively narrow; laterally straight sided; 1.8 × longer than basal width; with apical 1 / 5 projecting past the top of the gonocoxites. Hypandrium vestiture long, dense, on the apical 1 / 3. Gonocoxite apical 1 / 2 parallel sided; gonocoxites widest in basal 1 / 2, narrowing apically; rounded apically. Gonocoxite vestiture on the lateral 1 / 2, of apical 1 / 3, mostly short, laterally projecting. Gonostylus with parallel sides; and narrow apical region. Phallus near parallel sided; narrowing apically.

Female. Same as male, except for genitalia dimorphism and the following characters: Head. Frons width anterior to ocellar tubercle 0.8 × the width above antennal insertions.

Geographical distribution.

Prosoeca peringueyi is the most widespread species in this clade. It occurs from Khuboes near the Namibia / South Africa border in the north to Piekenierskloof pass in the Western Cape Province in the south (pers. obs., A. G. Ellis), with a distribution gap within the Knersvlakte (Fig. 1 View Figure 1 ).

Biology.

The P. peringueyi complex is known to visit many plant species ( Manning and Goldblatt 1996; Manning and Goldblatt 2000; Pauw et al. 2020) in both Fynbos and Succulent Karoo biomes. It is however, not precisely known for all plant species whether P. peringueyi and P. torquata are pollinators of the same suite of plants or if they partition these floral resources. Prosoeca peringueyi is known with some certainty, from specimen labels, to visit Lapeirousia pyramidalis , Pelargonium magenteum , Lapeirousia silenoides , Lapeirousia jacquinii , Pelargonium incrassatum , and Sutera fruticosa .

Comments.

Prosoeca peringueyi has a degree of genetic differentiation between the populations north and south of the Knersvlakte (mean 6.27 %). This genetic disjunction is supported by a difference in wing venation, with the cross vein between R 4 and R 2 + 3 just beyond fork of R 4 and R 5 present north of the Knersvlakte and absent in the south. As the wing vein character is not functional and the genetic difference below the usual threshold for species delineation, we consider this to be a single species.