Morellia simplex
Around 9-10mm, a dark grey/black fly with a bold but short white stripe at the front of the thorax. The dark grey abdomen typically has a pale tip. The Morellia genus can be recognised by this generally dark colour, with vein m gently curving towards the wing margin and the middle tibia without a strong posteroventral seta, though posterodorsal and posterior setae usually well developed. Morellia simplex is probably the commonest of the genus and can be recognised by having a parallel-sided prosternum with lateral bristles.
Easily confused with Polietes domitor, but they are easily separated by the wing venation.
- Vein m gently curving
- Middle tibia without a strong posteroventral seta
- Posterodorsal and posterior setae usually well developed
- Overall appearance dark grey to black
- Prosternum parallel sided and with lateral bristles
- Grey dusting on the abdomen
- Grey dusting on the thorax visible when viewed from behind
It breeds in cattle dung so is usually found around cattle pasture.
Peaks in April/May and in August/September.
It is sometimes referred to as a Sweat Fly and it can be a particular nuisance to cattle.
Widespread and quite common in Britain.
Fairly common in Leicestershire and Rutland
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Species profile
- Species group:
- insect - true fly (Diptera)
- Kingdom:
- Animalia
- Order:
- Diptera
- Family:
- Muscidae
- Records on NatureSpot:
- 15
- First record:
- 24/05/2008 (Nicholls, David)
- Last record:
- 21/06/2025 (Nicholls, David)
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% of records within its species group
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