Blera fallax or the pine hoverfly is a rare species

Rare species

A rare species is a group of organisms that are very uncommon or scarce. This designation may be applied to either a plant or animal taxon, and may be distinct from the term "endangered" or "threatened species" but not "extinct"....

 of hoverfly

Hoverfly

Hoverflies, sometimes called flower flies or syrphid flies, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring at flowers; the adults of many species feed mainly on nectar and pollen, while the larvae eat a wide range of foods...

 normally associated with mature pine tree in Northern

Northern Europe

Northern Europe is the northern part or region of Europe. Northern Europe typically refers to the seven countries in the northern part of the European subcontinent which includes Denmark, Estonia, Latvia, Lithuania, Norway, Finland and Sweden...

 and Central Europe

Central Europe

Central Europe or alternatively Middle Europe is a region of the European continent lying between the variously defined areas of Eastern and Western Europe...

.

Biology

The pine hoverlfy larva

Larva

A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...

, which are of the rat-tailed maggot

Rat-tailed maggot

Rat-tailed maggots are the larvae of some species of hoverfly, commonly Eristalis tenax. A characteristic feature of rat-tailed maggots is a tube-like, three segmented, telescoping breathing siphon located at their posterior end. This acts like a snorkel, allowing the larva to breathe air while...

 type, normally develop in damp rot holes of felled or felled pine trees, notably the Scots pine (Pinus sylvestris

Scots Pine

Pinus sylvestris, commonly known as the Scots Pine, is a species of pine native to Europe and Asia, ranging from Scotland, Ireland and Portugal in the west, east to eastern Siberia, south to the Caucasus Mountains, and as far north as well inside the Arctic Circle in Scandinavia...

), though it will occur with other conifers. Preference is for large stumps where there has been some heartwood softening by the fungus

Fungus

A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...

 Phaeolus schweinitzii

Phaeolus schweinitzii

Phaeolus schweinitzii, commonly known as velvet-top fungus, dyer's polypore,Norway Chicken, or dyer's mazegill, is a fungal plant pathogen that causes butt rot on conifers such as Douglas-fir, spruce, fir, hemlock, pine, and larch. P...

. Adult flies have been seen feeong on wild raspberry

Raspberry

The raspberry or hindberry is the edible fruit of a multitude of plant species in the genus Rubus, most of which are in the subgenus Idaeobatus; the name also applies to these plants themselves...

 flowers, but little else is known about adult behaviour.

Conservation

In Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

, attempts have been made on RSPB

Royal Society for the Protection of Birds

Bird Notes and News was first published in April 1903.The title changed to 'Bird Notes' in 1947. In the 1950s, there were four copies per year . Each volume covered two years, spread over three calendar years...

sites to create artificial rot holes in felled pine stumps. This has led to a slight increase in numbers of adults in some areas, though numbers are still very low and causing some concern.