T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Fly (Blossom fly) Dilophus nigrostigma

Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Hexapoda
Class: Insecta
Subclass: Pterygota
Order: Diptera
Suborder: Nematocera
Infraorder: Bibionomorpha
Superfamily: Bibionoidea 
Family: Bibionidae
Genus: Dilophus
Species: D. nigrostigma
Binominal name: Dilophus nigrostigma
Synonyms: Bibio nigrostigma, Bibio zealandicus, Dilophus spectabilis, Dilophus zealandicus
Common name: Blossom Fly, March fly, 

Dilophus nigrostigma is a fly endemic to New Zealand, its common name (March fly) originates in the Northern Hemisphere where it is spring in March. It is found throughout New Zealand including the Chatham Islands. Dilophus nigrostigma can be found feeding in a range of flowers in spring.
The males are a shining black and have a body length of about 8.0 mm. Wings are almost clear and are about 7.5 mm in length. The antennae is a dark reddish black, with 13 segments. The eyes are a reddish brown. Legs are also a shining black. There are prominent rows of hairs on the thorax. The halteres have a dark brown bulb and dark greyish-brown stalk.
The female has a body length of 7.0-8.0 mm; wing length 7.0-8.0 mm. It is similar to male except the thorax is shining reddish brown and its abdomen is a dark grey/brown. The head is a dark shining brown. The legs are a dark brown but the coxa and femur are red.

Female blossom fly, Dilophus nigrostigma. Females have a shiny red thorax.

A female fly with red thorax

A male fly totally black.

Male and female.

Mating flies.

Thanks to Wikipedia for text and information http://creativecommons.org/licenses/by-sa/3.0/