Mesembrius tarsatus (Bigot, 1883)

Jordaens, Kurt, Goergen, Georg, Skevington, Jeffrey H., Kelso, Scott & Meyer, Marc De, 2021, Revision of the Afrotropical species of the hover fly genus Mesembrius Rondani (Diptera, Syrphidae) using morphological and molecular data, ZooKeys 1046, pp. 1-141 : 1

publication ID	https://dx.doi.org/10.3897/zookeys.1046.57052
publication LSID	lsid:zoobank.org:pub:66E61C4E-FAFE-45DE-9145-DB38199BDEC3
persistent identifier	https://treatment.plazi.org/id/92B41985-235A-5D4C-8A99-00262C4BF2F1
treatment provided by	ZooKeys by Pensoft
scientific name	Mesembrius tarsatus (Bigot, 1883)
status

Treatment

Mesembrius tarsatus (Bigot, 1883) Figs 2 View Figures 1, 2 , 24 View Figures 23, 24 , 44 View Figures 43, 44 , 67 View Figures 64–69 , 81 View Figures 79–82 , 104 View Figures 101–106 , 125 View Figures 124–126 , 148 View Figures 147–150 , 159 View Figures 159–162 , 168 View Figures 166–171 , 189 View Figures 189–192 , 226 View Figures 217–228

Prionotomyia tarsata Bigot, 1883: CXXI.

Prionotomyia tarsata - Kertész (1910): 266 - Speiser (1913): 128.

Mesembrius tarsata - Curran (1939): 9.

Mesembrius tarsatus - Smith and Vockeroth (1980): 504.

Differential diagnosis.

Mesembrius tarsatus males are holoptic, have a loose black apical pile brush on the profemur, a black scutum with, dorsally, a pair of weakly-demarcated yellow pollinose vittae, an orange probasitarsus with a tuft of black pile on the posterior side and two black spots on the most distal tarsomere and a slender metatibia with a swelling in the posterior medial half. It can be distinguished from any other species by the apical pile brush of the profemur which is loose and entirely black (black dorsally, yellow ventrally in M. arcuatus sp. nov.; yellowish with some black pile interspersed in M. ingratus ) and by the rounded swelling on the metatibia (strongly compressed in M. arcuatus sp. nov.; with a deep groove in M. ingratus ). Females have a frons which is black pilose on its entire length, except laterally. It can be distinguished from other such females (except from M. sulcus sp. nov.) by the black legs, including the tibiae (tibiae yellow-brown in other species). It differs from the female of M. sulcus sp. nov. in tergite II which has a pair of large yellow-orange maculae which, laterally, reach to almost the posterior end (small pair of yellow-orange maculae which, latteraly, reach to halfway of the tergite length M. sulcus sp. nov.) and in tergite III which has a pair of clear anterolateral yellow-orange maculae (vague pair of maculae in M. sulcus sp. nov.).

Examined material.

Prionotomyia tarsata Bigot: Lectotype (hereby designated), male, “LECTOTYPUS” "SYN- // TYPE" " Prionotomyia // Prionotomyia tarsata Big." " Prionotomyia ♂ // Prionotomyia tarsata Bigot // Senegal " "ex. coll. Bigot, // Press. by // G.H. Verrall. // B.M. 1894234" "BMNH(E) # // 230741" " NHMUK 010369820" [NHMUK]. Paralectotype, male, "SYN- // TYPE" " Prionotomyia // Prionotomyia tarsata Big." " Prionotomyia ♂ // Prionotomyia tarsata Bigot // Senegal " "ex. coll. Bigot, // Press. by // G.H. Verrall. // B.M. 1894234" "BMNH(E) # // 230742" " NHMUK 010369821" "PARA- // LECTOTYPUS " [NHMUK] .

Other material

Democratic Republic of the Congo • 1♀; Banningville [= Bandundu], Kwilu River, Panga ; Aug 1945; Fain leg.; RMNH • 1♀; Haut-Katanga, Kasenga; 5 Mar 1912; J. Bequaert leg.; KMMA • 1♂; South-Kivu, Musingiro; 8 Oct 1922; Ch. Seydel leg.; KMMA • 1♀; Tshibinda; 21-27 Aug 1931; T.D.A. Cockerell leg.; NHMUK • 1♀; Eala; 5 Oct 1935; J. Ghesquière leg.; RMNH • 1♀; Eala; Aug 1936; J. Ghesquière leg.; RMNH • 1♀; Eala; Mar 1935; J. Ghesquière leg.; RMNH • 1♀; Eala; Oct 1936; J. Ghesquière leg.; RMNH • 1♀; Lulua, Kapanga; Nov 1928; Walker leg.; RMNH • 1♂; Lulua, Kapanga; Aug 1932; F.G. Overlaet leg.; RMNH . Kenya • 1♂; Naivasha, Fisherman’s Camp; 14 Mar 1993; M. De Meyer leg.; NMK • 4♂♂ 2♀♀; Nairobi ; Mar 1928; van Someren leg.; KMMA • 1♂; Nairobi ; 20 Mar 1921; A.F.J. Gedye leg.; NMK • 7♂♂ 2♀♀; Nairobi , Karura Forest ; 23 Nov 2017; PINDIP course leg.; KMMA . Malawi • 1♂; Mulanje Mountain ; 26 Nov 1912; S.A. Neave leg.; NHMUK • 1♂ 1♀; Zomba Plateau; 1 Dec 1911; collector unknown; NHMUK • 3♂♂; Zomba Plateau; 24 Nov 1980; B.R. Stuckenberg leg.; NMSA • 2♂♂; Zomba Plateau; date unknown; H.S. Stannus leg.; NHMUK • 1♂; Zomba Plateau; 24-27 Nov 1980; J.G.H. Londt and B. Stuckenberg leg.; NMSA • 7♂♂ 6♀♀; Zomba, Kuchawe Trout Farm; 8-11 Nov 2016; K. Jordaens leg.; KMMA . Senegal • 2♂♂; locality and date unknown; Bigot leg.; NHMUK • 1♂; Nema Ba ; 10 Nov 2016; S. Cavaillès leg.; SCPC . South Africa • 2♂♂; Barber Nature Reserve; 7 Oct 2015; A. Vujić et al. leg.; UNS • 1♂; KwaZulu-Natal, Dukuduku Forest Reserve; 18-19 Jul 1981; J.G.H. Londt and B. Stuckenberg leg.; NMSA • 1♂; KwaZulu-Natal, Umlalazi Nature Reserve ; 8 Nov 1997; J.G.H. Londt and A. Londt leg.; NMSA • 1♂; KwaZulu-Natal, Bluff Nature Reserve ; 3 Sep 2018; J. Midgley leg.; NMSA • 1♂; KwaZulu-Natal, Durban; 23 Apr 1920; C.N. Barker leg.; DMSA • 1♂; KwaZulu-Natal, Durban; 8 Feb 1919; C.N. Barker leg.; DMSA • 1♂; KwaZulu-Natal, Durban; Nov-Dec1945; H.W. Bell Marley leg.; DMSA • 1♂; KwaZulu-Natal, Pietermaritzburg, Botanical Gardens; 15 Nov 2018; J. Midgley leg.; NMSA • 1♂; KwaZulu-Natal, Ngoye Forest Reserve ; 29 Jan 1968; J.G.H. Londt leg.; NMSA • 1♂; KwaZulu-Natal, Ubombo Mountain Reserve ; 11 Oct 2019; D. Brothers leg.; NMSA • 1♂; KwaZulu-Natal, Umlalazi Nature Reserve ; 8 Nov 1997; J.G.H. Londt leg.; NMSA • 1♂; KwaZulu-Natal, Dukuduku Forest , 4♂♂ W of St. Lucia; 26 Nov 1971; M.E. Irwin leg.; NMSA . Uganda • 1♂; between Jinja and Bussia; 28 Jul-1 Aug 1911; S.A. Neave leg.; NHMUK • 1♀; Jinja; Oct 1930; van Someren leg.; NHMUK • 2♂♂ 1♀; between Sewiza and Kampala; 27-31 Aug 1911; S.A. Neave leg.; NHMUK • 1♂; Entebbe; 17 Aug 1911; C.C. Gowdey leg.; NHMUK • 1♂ 2♀♀; Entebbe; 21 Aug 1911; C.C. Gowdey leg.; NHMUK • 1♀; Entebbe; 31 Aug 1911; C.C. Gowdey leg.; NHMUK • 1♂; Entebbe; 18-20 Nov 1911; C.C. Gowdey leg.; NHMUK • 1♀; Entebbe; 11 Aug 1912; C.C. Gowdey leg.; NHMUK • 1♂; Entebbe; 16 Aug 1912; C.C. Gowdey leg.; NHMUK • 2♂♂; Entebbe; 17 Aug 1912; C.C. Gowdey leg.; NHMUK • 2♂♂; Entebbe; 27 May 1912; C.C. Gowdey leg.; NHMUK • 3♂♂ 1♀; Entebbe; 7-9 May 1912; C.C. Gowdey leg.; NHMUK • 2♂♂ 2♀♀; Entebbe; 3 Nov 1912; C.C. Gowdey leg.; NHMUK • 1♂ 1♀; Entebbe; 14 Nov 1912; C.C. Gowdey leg.; NHMUK • 6♂♂ 1♀; Entebbe; 18-20 Nov 1912; C.C. Gowdey leg.; NHMUK • 1♂; Entebbe; 13 Oct 1912; C.C. Gowdey leg.; NHMUK • 1♂ 1♀; Entebbe; 16 Oct 1912; C.C. Gowdey leg.; NHMUK • 1♂; Entebbe; 3 Sep 1912; C.C. Gowdey leg.; NHMUK • 1♂; Entebbe; 18-20 Nov 1911; C.C. Gowdey leg.; NHMUK • 1♂; Entebbe; 1-14 Sep 1912; C.A. Wiggins leg.; NHMUK • 1♂; Entebbe; 1-11 Sep 1911; S.A. Neave leg.; NHMUK • 1♂; South of Maseka, Katera Forest ; May 1972; E.B. Babyetagara leg.; CNC • 5♂♂ 2♀♀; N.W. shores of Vic. Nyanza; 12-15 Sep 1911; S.A. Neave leg.; NHMUK • 5♂♂ 3♀♀; Northern Buddu ; 16-18 Sep 1911; S.A. Neave leg.; NHMUK • 1♂; Nsoje River ; 2 Mar 1911; van Someren leg.; NHMUK • 1♂; N. Ankole, Nyrbthozi; 21 Jan 1975; M.K. Paulus leg.; CNC • 1♀; South of Lake George ; 17-19 Oct 1911; S.A. Neave leg.; NHMUK • 1♂; S.E. Ankole; 4-8 Oct 1911; S.A. Neave leg.; NHMUK • 1♂; Tero Forest ; 8 Jul 1912; C.C. Gowdey leg.; NHMUK • 2♂♂; S.E. Buddu, Tero Forest ; 26-30 Sep 1911; S.A. Neave leg.; NHMUK • 1♀; Toro, Duro River ; 6 Mar 1911; van Someren leg.; NHMUK • 1♂ 1♀; Toro, Duro River ; 12 Mar 1911; van Someren leg.; NHMUK • 1♂; Tororo; 25 Jan 1967; F.K. Masasai leg.; NHMUK • 1♂; District West Uganda, W. Ankole; 19-24 Apr 1973; H. Falke leg.; CNC • 1♂; District West Uganda, W. Ankole ; 30 Dec 1975; M.K. Paulus leg.; CNC • 1♀; locality and date unknown; R.C. Bradley leg.; NHMUK . Zambia • 1♂; Lake Bangweulu, Kapola, N. of Kapata ; 27 Oct 1946; collector unknown; NHMUK . Zimbabwe • 1♂; Mporokoso ; 2 Aug 1909; S.A. Neave leg.; OXUM .

Re-description male

(Fig. 24 View Figures 23, 24 ). Body length: 13.1-15.4 mm. Wing length: 9.7-10.9 mm.

Head (Fig. 67 View Figures 64–69 ). Eyes bare; holoptic, eye contiguity somewhat shorter than length of ocellar triangle. Face white with dark medial vitta; white pilose; white pollinose. Vertical triangle black; black pilose; yellow pollinose on ventral half. Distance between lateral ocellus and eye margin 1/2 width of ocellus. Occiput yellow; yellow pilose, with some shorter and thicker black pile near eye margin; yellow and white pollinose. Frontal triangle short; yellow-white; with some long, black pile; yellow pollinose. Frontal prominence shiny black with orange-brown apex. Antenna black; postpedicel white pollinose; antennal arista reddish-brown.

Thorax. Scutum black with, dorsally, a pair of weakly-demarcated yellow pollinose vittae which fade out posteriorly; lateral yellow pollinose vitta very faint to absent; yellow and black pilose. Scutellum dark brown to black with a lighter posterior border; with long yellow pile and shorter black pile, the latter most prominent in the posterior half.

Legs (Fig. 168 View Figures 166–171 ). All legs black, but protarsus reddish-brown; black pilose. Proleg (Fig. 159 View Figures 159–162 ): Femur dorsoventrally flattened; posterodorsal side with yellow, long pile and some long black pile in proximal half; with apical pile brush of long, relatively loose and curved black pile; with long black pile anteroventrally. Basitarsus orange; with a tuft of black pile on posterior side and two black spots on the most distal tarsomere. Mesoleg: Femur with long yellow and black pile. Metaleg (Fig. 189 View Figures 189–192 ): Femur with long and thin yellow pile; with some black pile towards distal end; with a patch of shorter and thicker black pile ventroproximally. Tibia with long black pile, especially in distal 2/3; ventrally with a swelling on distal 1/3.

Wing (Fig. 148 View Figures 147–150 ). Entire wing uniformly dense microtrichose.

Abdomen (Fig. 104 View Figures 101–106 ). Tergite II with a pair of very large yellow-orange rounded maculae; black marking hourglass-shaped; posterior black marking equal in size to anterior black marking and with a medial white pollinose area; yellow pilose, but black pilose on posterior black marking and on posterolateral corners. Tergite III and IV with broad yellow-orange fascia, with large black, white pollinose marking on posterior 2/3; black pilose on black marking and adjacent parts of yellow-orange fascia, yellow pilose on remainder of yellow fascia and on lateral sides.

Genitalia (Fig. 226 View Figures 217–228 ). Epandrium: Dorsal lobe of surstylus broadly rounded; with short black spines on almost entire surface; dorsally long yellow pilose. Ventral lobe of surstylus straight; bare.

Description female

(Fig. 44 View Figures 43, 44 ). Body length: 11.0-13.2 mm. Wing length: 12.7-15.6 mm. Similar to the female of M. sulcus sp. nov., but the maculae on abdominal tergite II are larger and triangular (Fig. 125 View Figures 124–126 ). Head as in Fig. 81 View Figures 79–82 .

Distribution.

Democratic Republic of the Congo, Kenya, Malawi, Senegal, South Africa, Uganda, Zambia and Zimbabwe.

Comments.

See M. sulcus sp. nov.