Jimmy McKellar
| Conops quadrifasciatus | Sicus ferrugineus | Physocephala nigra | Myopa buccata |
Introduction
The HBRG Conopid recording scheme started as a result of the realisation that we had very few records of these interesting flies. Being quite distinctive they offered us the chance to improve map coverage with a little effort. The baseline was sparse so any records were sure to add to our knowledge. These small parasitic flies are good wasp mimics that target hymenoptera. Known hosts include bumblebees and solitary bees and may include social wasps. By flying from a flower head and intercepting a passing host, these flies grapple with the bees and lay their egg (one per host) through the membrane between body segments. They can often be found on flowers in summer though they can sometimes be mistaken for hoverflies or parasitic wasps.
This group is poorly represented in Highland by only four species but this very lack of species offers real opportunity for research, there being less likelihood of misidentification. There are plates of three of the four species mentioned below in Chinery (1986), p 209.
We have had more records of this species than the others. The new records consolidate what we knew and slightly enlarge the area where this fly is known to occur. By plotting the range of dates on which it was recorded along a time-line it becomes clear that the flight period is at least from late July until almost the end of September. Unfortunately I could find no mention of flight periods in any literature for comparison. However I contacted David Clements (DC), the national recording scheme recorder, who stated Conops quadrifasciatus has quite a long flight period from mid to late summer, that is from early June to early October but peaking in July-August. This seems to suggest we are probably missing records in June and July even allowing for a shorter flight period this far north. With a few exceptions the absence from the west suggests the insect is either rare, not common, or under recorded there. This may be the result of observer bias or a genuinely rare fly on the west coast. Top.
Conops quadrifasciatus. Dark green - up to 2002. Mid green - added 2003. Pale green - added 2004.
Photo © Jimmy McKellar
Left - C. quadrifasciatus is very wasp-like in the field. The forward-pointing antennae are distinctive, and the long tongue is well shown in the picture. This is a male. The female is similar, but has a prominent outgrowth on the underside of the abdomen.
We have only managed to add a few records for this species but they have pushed the known distribution area out to the east and filled in a few gaps. As can be seen from the map the distribution is somewhat coastal around the inner Moray Firth. We still have no records from other areas which is surprising. Our records show flight times from late June to early September. DC said the flight times are similar to C. quadrifasciatus but seem to go on in greater numbers in late summer (August-September). The two areas, Black Isle and Easter Ross seem to be the best places to search next for this species. Top.
Sicus ferrugineus. Dark green - up to 2002. Mid green - added 2003. Pale green - added 2004.
Photo © Jimmy McKellar
Left - S. ferrugineus is a rather ugly brown fly. The large head and long proboscis are well shown in this picture.
Only one more dot for this species but it is a difficult to identify and is possibly more widespread than our map depicts. DC describes it as seeming to fly in early to mid summer, from about mid May to the end of July, with most records in June-July. He confirmed P. nigra as a scarce species and asked if we find this mainly in heathland situations? As I am unable to answer this question we really ought to try to confirm which habitat it prefers. Top.
Physocephala nigra. Dark green - up to 2002. Mid green - added 2003.
Photo © Murdo Macdonald
Left - P.nigra showing the large head and forward-pointing antennae of the family. The patterned wings of this species, and the yellow markings on the abdomen are distinctive.
This species is more difficult, not only to find but also to identify so records have remained few. This is the distribution map for 2004 and is identical to the one we started with. Since 2002 there have been no further records but information from DC confirmed this as a vernal species with the great majority of records he has occurring in the April-May period, but with outliers from about mid-March to mid-June. Top.
Myopa buccata, all records to 2004.
Maps prepared with DMAP.
Photo © Jimmy McKellar
Left - M. buccata showing the characteristic white face. This is less distinctive than the other conopids, and is probably overlooked.
Details of records including your address, date of record, place (with six figure grid reference), altitude, flowers visited or any other useful details may be sent to Jimmy McKellar: .
References:
Smith, Kenneth G. V. (1969). Handbooks for the identification of British Insects, Diptera Conopidae Vol. X. Part 3 (a). Royal Entomological Society.
Chinery, M. (1986). Insects of Britain and Western Europe. Collins, London.
Clements D. K. (1997). The Enemy Within: Conopid flies as parasitoids of bees and wasps in Britain. British Wildlife 18(5): 310-315.
McKellar, J. & Macdonald, M. (2002). Conopid Flies. Highland Biological Recording Group Newsletter 15: 20.
McKellar, J. (2003). Conopidae (Diptera) in Highland. Highland Biological Recording Group Newsletter 16: 18-19.
McKellar, J. (2004). Conopid Flies - progress report. Highland Biological Recording Group Newsletter 17: 9-10.
