miner: A large upper-surface (often almost full depth) blotch, without
a trace of an initial corridor, beginning in the very tip of a leaf
segment. The full grown larva spins itself a disc shaped cocoon
within the mine. Just before, it has made a circle of perforations
in the upper epidermis with its mandibles. The cocoon is formed,
attached to the upper epidermis, and the larva becomes immobile.
The perforated circle of epidermis starts to dry, warps, and finally
becomes detached from the surrounding tissue and drops to the ground.
The resulting excision has a diameter of about 7 mm, and is best
seen when the leaf is held against the light (Bladmineerders van Europa).
mine is also illustrated in British
The larvae of sawflies have a head capsule, chewing mouthparts with opposable mandibles, six thoracic legs and abdominal legs (although they may be reduced) (see examples).
The larva is illustrated in British
leafminers. Like all Heterarthrus species the thoracic
feet are reduced to small stumps (Bladmineerders van Europa).
The pupae of sawflies have visible head appendages, wings and legs which lie in sheaths.
Hosts in Great Britain & Ireland:
of year - larvae: Univoltine: early summer (British
of year - adults: Currently unknown.
Full synonymy and references are listed in ECatSym - Electronic World Catalog of Symphyta.
in Great Britain & Ireland: Widespread in England including
Bedfordshire (VC30), Berkshire (VC22), Buckinghamshire (VC24), Cumberland (VC70), Middlesex (VC21),
North Wiltshire (VC7), North-west Yorkshire (VC65), South Wiltshire (VC8), South-east Yorkshire (VC61), South-west Yorkshire (VC63), Surrey (VC17), Warwickshire (VC38), West Lancashire (VC60),
Westmorland (VC69) and Worcestershire (VC37) (NBN
recorded in the Republic of Ireland (van Achterberg in Fauna Europaea).
NBN Grid Map:
elsewhere: Widespread in continental Europe including Austria,
Corsica, Croatia, Czech Republic, French mainland, Germany, Italian
mainland, Poland, Sweden, ? Switzerland and ? Ukraine (van Achterberg
in Fauna Europaea).
NBN Interactive Grid Maps of known host species:
British and Irish Parasitoids in Britain and elsewhere: