BRITISH BLOWFLIES (CALLIPHORIDAE) AND WOODLOUSE FLIES (RHINOPHORIDAE)

Draft key to British Calliphoridae and Rhinophoridae Steven Falk 2016
then discovered at Tide Mills, Sussex in 2010, and it can be adundant here throughout
summer. Considered a recent colonist in Britain capable of exploiting woodlice on
boats or cargo. It was recently added to the South American list (Mulieri et. al., 2010).
A number of very similar species occur on the continent.
Stevenia deceptoria male (left) and female (right)
Tricogena rubricosa (Meigen, 1824)
Red-shinned Woodlouse-fly
Description & similar species WL 3-4mm. A smallish, heavily-dusted species that is
abundantly distinct from other rhinophorids through its rather stocky build, wing
venation (with cell R4+5 usually narrowly open), yellow-tipped scutellum, and
partially red legs (more extensively so in females than males). Males have the sides of
tergites 1+2 and 3 reddish, and large, projecting lobes arising from sternite 5 which
make the tip of the abdomen appear swollen. Both sexes have the frons about onethird
the width of the head, that of the female slightly broader and with the
parafacialia slightly wider. Females have the second antennal segment reddish but in
males it is mostly dark. More likely to be confused with a small tachinid than other
rhinophorids in the field.
Variation The tibiae are variably darkened basally and the extent of red varies on the
femora. Moderate size variation.
Flight season Late May into September.
Tricogena rubricosa male (left, Photo: Dick Belgers) and female (right, Photo: P. Walter). Notice the
orange tip to the scutellum of both sexes and the protruding lobe of sternite 5 in the male.
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