Megatrigon sexmaculatus, Doczkal & Radenković & Lyneborg & Pape, 2016

Doczkal, Dieter, Radenković, Snežana, Lyneborg, Leif & Pape, Thomas, 2016, Taxonomic revision of the Afrotropical genus Megatrigon Johnson, 1898 (Diptera: Syrphidae), European Journal of Taxonomy 238, pp. 1-36 : 23-24

publication ID	https://doi.org/ 10.5852/ejt.2016.238
DOI	https://doi.org/10.5281/zenodo.3854666
persistent identifier	https://treatment.plazi.org/id/03EA327E-FFF7-EC00-FDD6-EB0AFA91FE98
treatment provided by	Valdenar
scientific name	Megatrigon sexmaculatus
status	sp. nov.

Treatment

Megatrigon sexmaculatus View in CoL sp. nov.

urn:lsid:zoobank.org:act:C2AE7999-2A17-4871-AA30-9614966291FC

Figs 1F View Fig , 2G View Fig , 3F View Fig , 7F View Fig , 10F View Fig , 11F View Fig , 15 View Fig

Diagnosis

Golden-haired species with three pairs of silver spots on tergites 2–4 ( Figs 1F View Fig , 7F View Fig ). Silver spots on tergite 3 completely and densely setose, setae directed towards the lateral margin, i.e., turned ca. 90° in relation to longitudinal axis. Vertex ( Fig. 2G View Fig ) completely covered with dense, yellow-golden microtrichia except narrow bare stripe along the posterior margin.

Etymology

The species epithet, which is formed as an adjective, is derived from the Latin words sex (= six) and macula (= spot), alluding to the three pairs of silver spots on abdominal tergites 2–4.

Type material

Holotype

SOUTH AFRICA: ♁, Eastern Cape, Strowan, Grahamstown , 10 Oct. 1967, C. Jacot-Guillarmod leg. ( AMGS).

Paratype

SOUTH AFRICA: 1 ♁, Eastern Cape, Hilton, Grahamstown, sandpile, 25 Oct.1977, F.W. Gess leg. ( AMGS).

Description

LENGTH. Body 7.5–8.0 mm, wing 5.5 mm.

HEAD ( Figs 2G View Fig , 3F View Fig ). Face and frons similar to M. argenteus comb. nov.; ocellar triangle isosceles without groove; length of post-ocular orbit as usual, but a little larger than in M. argenteus comb. nov. 0.09–0.10 × width of head; postpedicel ( Fig. 3F View Fig ) larger than in M. argenteus comb. nov., 1.6–1.8 × as long as deep; 2.2 × as long as pedicel.

THORAX. Submedian microtrichia present on mesoscutum only anteriorly as triangular markings and as small spots at the level of transverse suture, besides two distinct, long lateral microtrichiose stripes; supraalar setae yellow; microtrichia on mediotergite covered about 0.4 of width.

WING. Yellow setae on costagium.

LEGS. Setae on legs all light; of tarsi, only tarsomere 1 and to a lesser extent tarsomere 2 of metaleg dorsally darkened.

ABDOMEN ( Figs 1F View Fig , 7F View Fig ). Tergites covered with relatively long, dense yellow-golden setae, without black ones; lateral silver spots on tergites 2–4 triangular, relatively large: on tergites 2+3 almost reaching the corners, tapering towards the middle of tergite where they approach each other; spots on tergite 4 anterior, small, widely separated from each other and lateral margin, but touching anterior margin. Male genitalia in Figs 10F View Fig , 11F View Fig .

Distribution

Afrotropical – South Africa (Eastern Cape) ( Fig. 15 View Fig ).

Subgroup 2

Male tergites without silver spots, i.e., microtrichiose spots not reflecting, tergites 2+3 more convex.