| Darkwinged Fungus Gnat (Sciaridae or Lycoriidae) : Sciara sp., Bradysia sp.
Keroplatidae: Orfelia sp.
Darkwinged fungus gnats are small, 4-6 mm long, black fragile insects. The adult insects fly zigzag over the substrate surface.
The 4-7 mm long larvae are transparent, whitish, slim with a black head capsule. They live in humid substrates and eat decomposing plant tissue, but big populations can also damage living plants. The darkwinged fungus gnats often occur in connection with fungus infestation in the thick roots of Phalaenopsis and Paphiopedilum. Weak plants or plants pre-damaged by harmful fungi are very attractive places to lay their eggs. The larvae are often imported into the stands in sphagnum.
The eggs are small, oval, transparent whitish and lain in humid substrates. The development from egg to adult takes about 4 weeks. The main species found in greenhouses are Sciara and Bradysia.
The Orfelia larvae are significantly bigger and slimmer, 15-20 mm long animals have been found in roots. The adult animals (8-10 mm) are also much bigger than the darkwinged fungus gnats and also markedly differ in habitus. The back part of the body has horizontal stripes. Most animals of this gnat species all over the world live on funghi, fungus infested substrates, in moss or under the barks of trees. This may confirm the theory that the gnat was imported in orchid-breeding companies in substrate containing bark and sphagnum.