Cerodontha (Cerodontha) denticornis (Panzer, 1806)
This species is notable for its color variation. The darkest flies are normally found in the spring and early summer from April to June, the palest from June to September. In the majority of specimens, the coloration is intermediate (Spencer, 1973, Nowakowski, 1973). Mesonotum greyish, abdominal tergites rather brown, both subshining. Frontorbital bristles only slightly inwards directed. Frontorbital setulae sparse, situated in one row together with the bristles.
IMPORTANT CHARACTERS (Spencer, 1973)
Adults
Wing length: 1.8 - 2.6 mm. Third antennal segment with strong spine.
Immature stages
Cephalopharyngeal skeleton as shown on the picture, thin, mouth hooks alternating regularly (Cer denticornis ceph.pct) The large number of bulbs of anterior posterior spiracles are arranged tree-like (Cer denticornis Larva SEM3.pct).
BIONOMICS
The larvae live mainly in the leaf sheath of grasses and pupate inside the mine. Normally, above the sheath a small part of the light green mine is visible. The mine of the sheath is almost invisible from outside. As in most other Cerodontha the mine is extremely thin, corresponding with the laterally flattened first segments and the narrow mandibles. There are many overlapping generations per year.
HOST PLANTS
Avena sativa L., Hordeum vulgare L., Triticum aestivum L., many fodder and wild grasses, including Agropyron, Dactylis, Festuca, Holcus, Phleum, Poa.
DISTRIBUTION
Probably Holarctic distribution. Widely distributed throughout Europe records exist from Morocco (Spencer, 1967), Afghanistan and Japan.
In central Europe Cerodontha denticornis is one of the most abundant species (von Tschirnhaus, personal communication).
ECONOMIC IMPORTANCE
Cerodontha denticornis is one of the most abundant agromyzid species at least in Europe. The species occur both on pastures and on cereal crops but records of damage are rare. Nonetheless the species should be regarded as potential pest since, due to their inconspicuous feeding pattern, the damage could have been easily overlooked in the past.