Phytomia natalensis (Macquart)

Meyer, Marc De, Goergen, Georg & Jordaens, Kurt, 2020, Taxonomic revision of the Afrotropical Phytomia Guérin-Méneville (Diptera: Syrphidae), Zootaxa 4803 (2), pp. 201-250 : 224-226

Phytomia natalensis (Macquart)

( Figs 10 , 50 , 72 , 93 )

Eristalis natalensis Macquart, 1850: 438

Megaspis natalensis var. rufifacies Doesburg, 1955: 3

Megaspis natalensis var. varipes Doesburg, 1955: 3

Material examined. HOLOTYPE ( natalensis ): ♀, SOUTH AFRICA, Port-Natal [= Durban area] ( MNHN) (head missing in holotype) . HOLOTYPE ( var. rufifacies ): ♂, CONGO (DR), Eala , January 1936 [not 1935 as in origi- nal description], J. Ghesquière ( KBIN) . PARATYPES ( var. rufifacies ): CONGO (DR), Eala, 1♀, March 1936; 1♂, August 1936; 1♂, Bombutu, S. Salonga , June 1936 ; 1♀, Bolingo, rives Busira , 23.VI.1936, all J. Ghesquière ( KBIN) . HOLOTYPE ( var. varipes ): ♂, CONGO (DR), Eala , March 1936, J. Ghesquière ( KBIN) . PARATYPES ( var. varipes ): Eala, 1♂, March 1936; 1♂, 22.V.1935; 1♀, February 1936, all J. Ghesquière ( KBIN) . Other material: ANGOLA, 1♂, 50km N Quiculongo, September–October 1957, G.H. Heinrich ( CNC) . BENIN, 1♀, Aplaoué , Feb- ruary 2006, G. Goergen ( IITA) . CAMEROON, 1♀, Lolodorf, A.I. Good ( CNC) . CONGO (DR), 1♂, Abimva, Uele , 1925, L. Burgeon ( KMMA) ; Bambesa , 1♂, 15.IX.1933; 1♂ 1♀, December 1933; 1♀, February 1934, all H.J. Brédo ( KMMA) ; 5♀, Dakwa, Uele , 9.VII.1933, J.V. Leroy ( KMMA) ; 1♀, Irumu ( Penge ), 1.III.1914, J. Bequaert ( KMMA) ; Kapanga , Lulua , 1♀, November 1928, Walker ( KMMA) ; 1♂, August 1932; 1♂, April 1933; 1♀, May 1933; 1♀, October 1933, all G.F. Overlaet ( KMMA) ; 1♀, Kere–Kere, Kilo , 1949, Turco ( KMMA) ; 1♀, Keshero ( Goma ), N Kivu, 10.II.1952, A.E. Bertrand ( KMMA) ; 1♀, Kivu, September–October 1925, Prince Leopold ( KMMA) ; 2♀, Luputa, Lomami , May 1935, Bouvier ( KMMA) ; 1♀, Lusuku, Lomami , December 1930, P. Quarré ( KMMA) ; 1♀, Mongati , E of Kinshasa, 26.VII.1968, P. Elsen ( KMMA) ; 1♀, Poko, Uele , August 1913, Lang & Chapin ( KMMA) ; 4♀, Sandoa, Kapanga , September 1928, Walker ( KMMA) ; 1♀, Uele River , J. Rodhain ( KMMA) ; 1♀, Yakoma , February 1932, H.J. Brédo ( KMMA) . GABON, 1♀, Lambaréné, Ogooué , 1911, R. Ellenberger ( MNHN) . GHANA, 1♂, Kumasi , May 2008, G. Goergen ( IITA) ; 1♀, N of Kibi, Atewa Range forest reserve, 14.VI.2006, K. D.B. Di- jkstra ( MZH) . KENYA, 1♀, Malindi , May 1973, H. Falke ( CNC) . NIGER, 1♀, Dosso, October 2006, G. Goergen ( IITA) . NIGERIA, 1♂, Ile-Ife , 31.XII.1969, J.T. Medler ( CNC) . TOGO, Kloto , 1♀, December 2002, 3♂, January 2004; 1♂ 2♀, March 2004; 2♀, December 2004; 1♀, February 2005; 1♂, March 2005; 1♂, November 2005; 1♀, November 2006; 7♀, December 2008; 1♂, November 2015; 1♂, December 2016, all G. Goergen ( IITA) ; 1♂, Mt Agou , February 2002, G. Goergen ( IITA) . UGANDA, 1♀, Budongo Forest , April 1972, E.B. Babyetagara ( CNC) ; 1♂, Bwamba, July–August 1946, V.G.L. van Someren ( CNC) ; 2♀, Entebbe , April 1973, H. Falke ( CNC) ; nr En- tebbe, 3♀, 23–31.I.1973; 5♀, 1–14.II.1973, all H. Falke ( CNC) ; 1♂, Ibanda, 23–28.XII.1972, H. Falke ( CNC) . P. natalensis var. rufifacies : CONGO (DR), 1♀, Bambesa , February 1934, J. Brédo ( KMMA) ; 1♀, Dima , 15.IX.1908, A. Koller ( KMMA) ; Eala , 1♀, September 1930, P. Staner ( KMMA) ; 1♂, July 1935; 1♂, August 1935, 1♀, Sep- tember 1935, all J. Ghesquière ( KMMA) ; 1♂, Kapanga, Lulua , April 1933, F.G. Overlaet ( KMMA) ; Medje , 1♀, April–May 1910, Lang & Chapin ( KMMA) ; 1♀, 25–30.VIII.1910, Lang & Chapin ( AMNH) ; Moma, Equateur , June 1925, J. Ghesquière , 6♂ ( KMMA) ; 1♂ ( AMNH) . P. natalensis var. varipes : CONGO (DR), 1♂, Eala , August 1935, J. Ghesquière ( KMMA) ; 1♀, Yakoma , 5–17.II.1932, H.J. Brédo ( KMMA) .

Body size. Body length (n=10): 12.5–17.5 mm. Wing length (n=10): 9.7–12.9 mm.

Redescription. MALE ( Fig. 10 ). Head. Eye bare; holoptic, touching for 3–5 times length of ocellar triangle, facets enlarged in dorsal half. Frons ground colour brownish; completely obscured by dense grey pollinosity except dorsally where weakly shining; dispersed pilosity of medium long pale pile (in var. varipes and rufifacies darker pile dorsally); rugose area shining black-brown, occupying about one-fourth to one-third of entire width and two-thirds to three-fourths of entire height; with shorter and more dispersed pale pile. Face ground colour black-brown (yellow

in var. rufifacies ); in upper half with dense whitish pollinosity, except below antennae where weakly shining; pilosity of short pale pile, along eye margins medium long pile; lower half to third weakly shining with more dispersed and very short pilosity; facial tubercle shining and bare, well developed. Gena dark brown to black-brown, largely shining, dispersed white pollinosity and long pale pilosity only in posterior part. Occiput dorsal third black, with greyish pollinosity; ventrally more densely yellow-white, with dispersed pale pile. Antennal segments brown to black-brown; arista yellow-brown, in basal half with medium long pile equal to width of pedicel.

Thorax. Scutum and scutellum black-brown ground colour, scutum with anterior third with dense yellowish pollinosity and medium long pale pilosity which is extending posteriorly along lateral margin to above the wing base (in var. varipes and rufifacies sometimes more greyish appearance); posteriorly with black-brown pollinosity and short black pilosity reaching all the way to posterior margin except for narrow fascia of variable length with more brownish pollinosity and yellow pilosity, sometimes the latter fascia with weak yellow pollinosity but then only in medial part anteriorly of scutellum; scutellum brownish pollinosity and very short black pilosity, along posterior margin somewhat longer. Pleural sclerites ground colour black, weakly shining with dense yellowish pollinosity, ventrally weaker greyish to greyish-brown pollinosity; covered with dispersed pile of long white pile, dorsal part of anepisternum more densely pilose, rarely anepimeron dorsally with partial black pilosity; meron, anterior part of katepisternum and anterior anepisternum bare.

Legs. Yellow-orange to brown. Fore leg, femur brown, apical margin narrowly paler; with dense short dark pilosity, anteriorly and posteriorly longer; tibia pale in basal two-fifths to half, otherwise brownish; with short black pilosity, except in basal part where pale; tarsal segments orange-brown. Mid leg as in fore leg, except tibia pale for basal half to three-fifths (in var. varipes tibia over entire length pale, apical part only darker yellow; with pale pilosity throughout). Hind leg, femur yellow-orange and with long pale pilosity in basal half, apically black-brown, with long black and more densely pilosity; tibia orange-brown to brown, pale in basal third; dorsally with short to medium long pale pilosity in basal part, black in apical part, ventrally with short to medium-long black pilosity (in var. varipes pale pilosity over entire length dorsally and ventrally); tarsal segments orange-brown.

Wing ( Fig. 50 ). Mainly hyaline, base for short part brownish. Calypters black-brown, with fringe of dark pile, rarely fringe at extremities paler.

Abdomen ( Fig. 72 ). Mainly yellow and black patterned. Terga 2–4 without distinct bullae but with small medial swelling. Tergum 2 yellow for entire length except posterior fourth (medially) to fifth (at lateral margin) where black; with short to medium long pale pile except in black part where short dark pile. Tergum 3 with posterior black fascia broadening medially, reaching anterior margin in the middle, laterally reaching lateral margin, anterolaterally slightly paler brown, sometimes well-defined small yellow maculae, reaching at most to halfway along lateral margin, sometimes also predominantly brown throughout; with short to medium long pilosity throughout, along lateral margins somewhat longer. Tergum 4 predominantly brown except occasionally anterolaterally with narrowly brownish patch; pilosity as in tergum 3 except pile longer. Terga 3 and 4 mainly with sparse black pollinosity except on medial swelling, anterolateral maculae and narrowly along posterior margin where shining. Sterna pale yellow, with widely dispersed long pale pile. Male genitalia as in Fig. 93 .

FEMALE. As male except for the following character states. Eye, facets of equal size; dichoptic. Frons in lower half more orange-brown; with greyish pollinosity, except in dorsal third where brown; covered with short dispersed pale pile, except in dorsal third where predominantly black (in var. rufifacies more extensively so); rugose area shining brown; occupying one-fourth of entire width and equal in height to at most 2 times length of ocellar triangle.

Distribution. Angola, Benin, Cameroon, Congo (DR), Gabon, Ghana, Kenya, Niger, Nigeria, South Africa, Togo, Uganda.

Comments. The specific status of P. natalensis and P. curta has been confusing over time. Phytomia natalensis was originally described by Macquart from a female specimen collected in South Africa (“Port Natal” corresponding with present Durban area). In his original description Macquart indicated on the coloration of the scutum “un peu de fauve au bord postérieur” (a bit of yellow at the posterior margin). Loew described P. curta , based on a female specimen also collected somewhere in South Africa (“Caffrerei” probably corresponding with present Eastern Cape area) by J.A. Wahlberg. From the same locality, Loew also studied a female specimen that he identified as P. natalensis . He pointed out the resemblance between both taxa but listed some morphological differences, in particular the coloration of the posterior margin of the scutum (black with yellow pile in P. natalensis ; yellow with yellow pile in P. curta ), and the extent of pollinosity on the third and fourth abdominal terga (more extensive in P. natalensis , largely weakly shining in P. curta ). Subsequent authors (see for example Karsch 1887; Speiser 1910; Bezzi 1912; Hervé-Bazin 1914) considered both as synonymous with varietal status at most. Bezzi (1915), however, considered them two distinct species after study of long series. This was followed by subsequent authors ( Curran 1927a; Doesburg 1955) but then revoked again and P. curta listed as synonym of P. natalensis ( Smith & Vockeroth 1980; Dirickx 1998). Representative specimens of both morphotypes were DNA barcoded. The DNA barcodes clustered in two well-differentiated (mean p-distance of 4.4 %) groups that correspond to the two morphotypes (i.e. curta and natalensis ). The type of P. natalensis was compared with representatives of the two clusters, as well as with images of the type of P. curta and the differences in extent of yellow pilosity and pollinosity of the scutum, as given in the respective redescriptions of both species, were considered consistent. To a lesser extent also the density of black pollinosity of abdominal terga 3 and 4 correspond with the descriptions. We, therefore, consider them as two separate taxa with specific status. In addition, a third entity with specific status was recognized: P. pallida , differentiated both on morphological grounds and DNA barcodes (see further).

Doesburg (1955) recognized two varieties within P. natalenis , based upon material from Congo (DR): P. natalensis var. rufifacies (differentiated by the medial part of the face wholly yellow) and P. natalensis var. varipes (differentiated by the hind tibia with dorsal pilosity wholly pale). Type material, as well as additional specimens examined (cf. list of material examined) were found to be consistent in these morphological differences. Some additional morphological differences were observed, in particular with regard to the distance the eyes are touching in the males and the thoracic pollinosity and pilosity. These morphological differences are indicated in the description above, and the material is listed separately. However, as no recent material could be obtained for these varieties, and thus not incorporated in the genetic analysis, we take a conservative approach and consider them currently as varieties and not of distinct specific status pending further research.

Figures

FIGURES 1–10. Phytomia spp., habitus, lateral view. 1. P. bullata (Loew) ♂ 2. P. aurigera Bezzi ♂ 3. P. kroeberi (Bezzi) ♂ 4. P. serena (Curran) ♀ 5. P. bulligera (Austen) ♂ 6. P. austeni sp. nov. ♂ 7. P. bezzii Curran ♂ 8. P. memnon sp. nov. ♂ 9. P. pubipennis Bezzi ♂ 10. P. natalensis (Macquart) ♂

FIGURES 49–60. Phytomia spp., right wing. 49. P. pubipennis Bezzi ♀ 50. P. natalensis (Macquart) ♂ 51. P. curta (Loew) ♂ 52. P. pallida sp. nov. ♂ 53. P. erratica (Bezzi) ♂ 54. P. fucoides Bezzi ♂ 55. P. fusca Hull ♀ 56. P. incisa (Wiedemann) ♂ 57. P. varians Curran ♂ 58. P. melas (Bezzi) ♂ 59. P. melas (Bezzi) ♀ 60. P. poensis (Bezzi) ♀

FIGURES 61–72. Phytomia spp., abdomen, dorsal view. 61. P. bullata (Loew) ♂ 62. P. aurigera Bezzi ♂ 63. P. kroeberi (Bezzi) ♂ 64–65. P. kroeberi (Bezzi) ♀ 66. P. serena (Curran) ♀ 67. P. bulligera (Austen) ♂ 68. P. austeni sp. nov. ♂ 69. P. bezzii Curran ♀ 70. P. memnon sp. nov. ♀ 71. P. pubipennis Bezzi ♂ 72. P. natalensis (Macquart) (M).

FIGURES 85–100. Phytomia spp., male terminalia, dorsal view. 85. P. bullata (Loew). 86. P. aurigera Bezzi. 87. P. kroeberi (Bezzi). 88. P. bulligera (Austen). 89. P. austeni sp. nov. 90. P. bezzii Curran. 91. P. memnon sp. nov. 92. P. pubipennis Bezzi. 93. P. natalensis (Macquart). 94. P. curta (Loew). 95. P. pallida sp. nov. 96. P. erratica (Bezzi). 97. P. fucoides Bezzi. 98. P. incisa (Wiedemann). 99. P. melas (Bezzi). 100. P. poensis (Bezzi).