Callicera rufa  - A Scottish icon

Callicera rufa is probably the most emblematic insect of the Caledonian pinewoods, on a par with other species such as the crested tit, twinflower or pine marten. It is intimately associated with the large ancient “granny” pines for which these woodlands are so famous. Although information on its life history and distribution was not fully understood until the 1990’s it is now recognised as an essential element of callicera.jpgthese ancient Scottish woods being found from the continental  Deeside to the oceanic pinewoods of Wester Ross. Recent work has also shown that Scotland holds a substantial proportion of the world population of this species - another reason for us to value it’s presence in our woods and to ensure its future survival.

The adult is a relatively large fly with a brightly shining body, the thorax covered in a fine pile of ginger red hairs. The legs are mainly orange and on the head are a pair of spectacular long, black antennae. Although you might have to persevere to catch a glimpse of an adult sunning on a tree stump or hovering around an old tree the spectacular larvae are present all year round in water fiiled rot holes and provide a relatively easy way of recording the distribution and population size of the species

eighe hole 2.JPG

Callicera rufa was the subject of early ground-breaking management trials for the conservation of saproxylic Diptera.  In order to boost and stabilise populations aArtificial rot holes were first created in pine trees at Beinn Eighe in north-west Scotland in 1990.  Holes were cut in the cleft of a twin-stemmed tree by use of a chain saw. The results surpassed our expectations -  we recorded larvae in the holes within a few months and they produced adult insects within two years of their creation. When we revisited the site in summer 2006 the holes were still being used by larvae and puparia were also present - 15 years on !
Reference :  MacGowan, I and Rotheray, G.E. Callicera rufa Schummel (Diptera Syrphidae) status and trends: an update. Dipterists Digest 2006 13, 113-118