Leaf-mine: Broad lower surface mine which generally starts at the leaf apex.The mine is somewhat irregular in depth. Frass in irregular black-green, frequently melted grains, mostly along the edges of the mine. Larva solitary. Pupation generally internal (Bladmineerders van Europa).

Larva: The larva is described by de Meijere (1928) and Nowakowski (1973).

Puparium: Flat, deeply segmented, shining metallic bluish-black; posterior spiracles projecting through the epidermis, widely separated, each on a conical projection with 3 bulbs (Spencer, 1976: 192, 193 (fig. 336)).

Metallic black with a violet or blue shine, flattened, and with the intersegmental constrictions fairly deep. Rear spiracula on two conical, divergent protuberances, drawn out in the shape of a dagger; they penetrate the epidermis. The spiracula with their base look like a capital M (Bladmineerders van Europa).

Comments: Festuca gigantea is treated as Schedonorus gigantea (Giant Fescue) by Stace (2010).

Hosts in Britain:

Hosts elsewhere:

Time of year - mines: June-October (Bladmineerders van Europa).

Time of year - adults: April, June-July.

Distribution in Great Britain and Ireland: Widespread and not uncommon. Kent (Maidstone), Surrey (Colley Hill), Norfolk (Middleton), Merioneth (Ganllwyd), Inverness (Aviemore), Aberdeen (Den of Pitlurgh), Elgin (Culbin Sands), Dunbarton (Bonhill) (Spencer, 1972: 102), Warwickshire (Coventry, Holbrooks) (Robbins, 1991: 136); Cambridgeshire, Glamorgan, Isle of Wight, North Hampshire, Stafford and West Kent (NBN Gateway - N.B. includes Watsonian Vice Counties having publicly available records that fall within or overlap the vice county border at 10km resolution or better i.e. a record for a vice county may relate to an adjacent vice county - for included datasets see NBN Grid map below).

NBN Grid map: Note that not all datasets on the NBN Gateway may be available on the map below. If you are an NBN Gateway registered user you can request access for missing datasets via the link 'Open interactive map in new window' below.

Distribution elsewhere: Widespread in continental Europe including Denmark, Finland, probably Finland and Sweden (Spencer, 1976: 192), The Netherlands, Belgium (de Meijere, 1924; Scheirs, de Bruyn and von Tschirnhaus, 1995); Luxembourg (Bladmineerders van Europa), Germany (Spencer, 1976: 554), Austria, Belarus, Czech Republic, Estonia, French mainland, Hungary, Latvia, Lithuania, Poland, Slovakia, Spanish mainland, Switzerland and Yugoslavia (Martinez in Fauna Europaea).

Also recorded Canada and the U.S.A. (Spencer, 1976: 192).

NBN interactive distribution map(s) of known host species in Great Britain and Ireland and elsewhere:

Parasitoids in Britain and elsewhere: Unknown.