Phytomia kroeberi (Bezzi)

Meyer, Marc De, Goergen, Georg & Jordaens, Kurt, 2020, Taxonomic revision of the Afrotropical Phytomia Guérin-Méneville (Diptera: Syrphidae), Zootaxa 4803 (2), pp. 201-250 : 210-212

Phytomia kroeberi (Bezzi)

( Figs 3 , 39–40 , 63–65 , 87 )

Megaspis kroeberi Bezzi, 1912: 423

Phytomia kroeberi Bezzi, 1915: 69

Phytomia neavei Bezzi, 1915: 70 syn. nov.

Dolichomerus kroeberi abdominalis Curran, 1927b: 364 Material examined. HOLOTYPE ( kroeberi ): ♀, TANZANIA, Nguelo , Usambara, H. Rolle ( BMNH) . HOLOTYPE ( neavei ): ♀, UGANDA, Entebbe , 1–11.IX.1911, S.A. Neave ( BMNH) . HOLOTYPE ( var. abdominalis ): ♀, CON- GO (DR), Moma, Equateur , June 1925, J. Ghesquière ( KMMA) . PARATYPE ( var. abdominalis ): CONGO (DR), same as holotype 1♀ ( AMNH) ; 1♀ ( KMMA) . Other material: ANGOLA, 1♀, 30km N Quiculungo , September–Oc- tober 1957, G.H. Heinrich ( CNC) . CAMEROON, 1♂, Eloumden , 15.XI.1965, B. de Miré ( MNHN) ; 2♀, Lolodorf , 17.XI.1913, A.I. Good ( CNC) . CONGO (DR), Eala , 1♀, September 1935; 1♀, October 1935; 1♀, August 1936; 1♀, 21.XI.1936, all J. Ghesquière ( KBIN) ; 1♂, Manyema, R. Mayné ( KMMA) (labelled as type but not part of type series, cf. Comments) ; Moma , Equateur , 1♀, June 1925, J. Ghesquière ( CNC) ; 2♂ 49♀, J. Ghesquière (3♀ speci- mens also labelled Prince Leopold as co-collector); 1♀, Stanleyville [=Kisangani], September 1913, Lang & Chapin ( KMMA) . KENYA, S. Masai, January 1933, Lewis , 1♀ ( BMNH) ; 1♀ ( NMK) . MALAWI, Cholo , 1♀, 11.XI.1920; 1♀, 8.I.1928, both R.C. Wood ( BMNH) ; 1♀, Mt Mlanji , 26.VII.1913, S.A. Neave ( BMNH) . SOUTH AFRICA, Upper Tongaat , Durban, Natal 2♀, XI.1919, C.N. Barker ( DNSM) . UGANDA, 1♀, nr Entebbe , 1–14.II.1973, H. Falke ( CNC) ; 1♀, Kemirondwa Valley , NE Kanyanchu, Kabarole Distr., 14.III.2012, M. von Tschirnhaus ( MZH) ; 1♀, Mabira Forest, Chagwe , 16–25.VII.1911, S.A. Neave ( BMNH) ; 1♀ [no locality], Chellanshal ( BMNH) . ZAM- BIA, 1♀, N. Lake Bangweolo, Luwingu , 9.VI.1908, S.A. Neave ( OXUM) . ZIMBABWE, 1♀, Bomponi , 5.VI.1963, D.M. Cookson ( NMSA) . Under kroeberi variety abdominalis : CONGO (DR) , 1♀, Kapanga , November 1932, G.F Overlaet ( KMMA) ; 2♀, Moma , June 1925, J. Ghesquière ( KMMA) ; 1♀, Stanleyville [=Kisangani], April 1915, Lang & Chapin ( AMNH) . Related to var. abdominalis (see Comments): TOGO, Kloto , 1♀, December 1999; 1♂, January 2016, both G. Goergen ( IITA) .

Body size. Body length (n=10): 11.7–13.5 mm. Wing length (n=10): 8.4–9.7 mm.

Redescription. MALE ( Fig. 3 ). Head. Eye bare; holoptic, touching for at least 3–4 times length of ocellar triangle, facets enlarged in dorsal half. Frons red-brown to black-brown; with brown pollinosity; dispersed pilosity of short pale pile, along dorsal margin somewhat longer dark pile; rugose area shining red-brown to black-brown, occupying half of entire width and at least three-fourths of height of frons. Face shining red-brown to brown, along facial tubercle and oral margin and gena yellow-brown to pale yellow or more orange; with greyish pollinosity dorsally and ventrally of facial tubercle; dispersed pilosity of short pale pile; facial tubercle oval shaped, hardly discernible. Three inconspicuous maculae present along inner margin of eye. Occiput dorsal third shining black to red-brown; ventral two-thirds with conspicuous silvery pollinosity, ventrally with dispersed pale pile. Antennal segments brown to orange-brown; arista yellow, in basal half with long pile equal to width of pedicel.

Thorax. Scutum brown to black-brown, along lateral margins somewhat paler or more orange; with brown pollinosity; pilosity of dispersed short dark pile, except along lateral margins dorsally of anepisternum where long pale or orange pile. Scutellum yellow-brown to rufous, with dispersed short pale orange pile. Pleural sclerites yellow-brown or orange-brown; covered (except meron, and anterior anepisternum) with long pale yellowish or orange pile.

Legs. Predominantly orange-red to reddish brown. Fore and mid leg with femur basally reddish to reddish brown, darkening towards apex where brown or black-brown, with short black pilosity except basally where paler; tibia brown, silvery in basal half dorsally, ventrally less so; with short black pilosity, except in silvery part where pale. Hind leg, femur orange-red to reddish brown, apex darker, ventrally with pronounced protuberance and tuft of dense black pilosity in apical fifth, otherwise with dispersed short dark and pale pilosity; tibia reddish to reddish brown, silvery part restricted to dorsal side and for basal sixth at most; with dark pilosity, except in silvery part where pale.

Wing ( Figs 39–40 ). Hyaline, sometimes more fumose. With variable brownish markings, consisting of microtrichia; usually as narrow marking along anterior margin from base to junction of vein R 4+5 with wing margin, sometimes less conspicuous in cell c; extending posteriorly in basal half of wing and almost reaching posterior margin, sometimes less extensively and partially hyaline. In all cases pronounced marking covering base of cell r 2+3, and extending posteriorly along medial part of cell r, and crossvein bm-cu. Second marking along basal third of cell r 2+3 and continued posteriorly over crossvein r-m. Calypters dark, except basal part where paler; with fringe of dark pile.

Abdomen ( Figs 63–65 ). Mainly shining yellow-brown to orange-red, lateral and posterior margins darker coloured to variable extent; terga 2–4 partly with dark orange pollinosity. Tergum 2 with one medial bulla, and two slightly rugose lateral plates; bulla entirely or partially dark. Terga 3–4 with one medial and two lateral bullae; medial bulla sometimes partially or completely dark. Sometimes ( var. abdominalis ) abdominal terga predominantly dark brown. Dispersed pale yellow pilosity on terga 3–4; more densely but short pilosity along lateral margins of tergum 2. Sterna yellow-brown; with widely dispersed short pale pile. Male genitalia as in Fig. 87 .

FEMALE. As male except for the following character states. Eye, facets of equal size; dichoptic. Frons reddish; with brownish pollinosity; dispersed pilosity of short pale pile in ventral third, dorsally darkish; rugose area darker reddish brown, occupying half of entire width and equal in height to twice length of ocellar triangle. Tiny silvery macula present along inner margin of eye at height of antennal insertion, extended narrowly medially; two additional inconspicuous maculae present along inner margin of eye.

Distribution. Angola, Cameroon, Congo (DR), Kenya, Malawi, South Africa, Tanzania, Uganda, Zambia, Zimbabwe. Probably also Togo (cf. Comments). Séguy (1953) mentions the species from Guinea.

Comments. Phytomia kroeberi and P. neavei were mainly differentiated by the coloration of the medial bullae on the abdomen, and the extent of the markings on the wing. However, these characters have proven to be very variable in the material studied, without clear correlation. The only differentiating character appears to be the coloration of the tibiae which is darker orange-brown in P. kroeberi while orange to red in P. neavei . Phytomia kroeberi specimens are recorded from Tanzania, Malawi and Zimbabwe while P. neavei material was found in Angola, Cameroon, Congo (DR), Kenya, Uganda and Zambia. We currently consider P. kroeberi and P. neavei to be synonymous, pending more extensive sampling throughout the entire distributional range. The variety abdominalis agrees with the above description except scutum, legs and abdomen are darker coloured with scutum and abdominal terga largely black-brown; dark markings on basal part of wing more pronounced and slightly smaller in size. Phytomia kroeberi var. abdominalis remains as a mere morphological variety. Two specimens from Togo are similar with the above, but the abdominal terga are less dark and bullae on abdominal terga 3–4 paler in colour. We place them tentatively here.

One specimen in the KMMA collection is labelled as type specimen of P. kroeberi , but does not belong to the type series. It was identified by Hervé-Bazin and the material was received in 1926 according to the collection registrar at KMMA. The erroneous labelling is most likely based on the publication by Hervé-Bazin (1914) where he mentions (p. 279) that this specimen belongs to a new species that will be described by Bezzi. There is no indication, however, that Bezzi studied the specimen nor was it included in the original type series as listed in Bezzi (1915).

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 37–48. Phytomia spp., right wing. 37. P. bullata (Loew) ♀ 38. P. aurigera Bezzi ♂ 39–40. P. kroeberi (Bezzi) ♀ 41. P. serena (Curran) ♀ 42. P. bulligera (Austen) ♀ 43. P. austeni sp. nov. ♂ 44. P. austeni sp. nov. ♀ 45. P. bezzii Curran ♂ 46. P. bezzii Curran ♀ 47. P. memnon sp. nov. ♀ 48. P. pubipennis 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).