Leaf-mine: A long thin linear gallery with frass in a thin line, sometimes broken. This distinguishes it form S.nylandriella, which never has linear frass throughout the mine. The gallery of S.magadalenae is also narrower than S.nylandriella. S. magdalenae can both be an edge miner or make a small mine in the leaf blade, or run along a vein (British leafminers).

Egg at the underside of the leaf, independent of the venation. The corridor is narrow from start to end, and compressed on a small space, sometimes following the leaf margin for a while, more often along a major vein. Frass in a narrow, regularly interrupted central line. In thick leaves the frass line is broader, and the corridor is shorter (Bladmineerders van Europa).

Larva: The larva is green (British leafminers; Emmet, 1983a; Schoorl et al., 1985a; Gustafsson and van Nieukerken, 1990a; Bladmineerders van Europa).

Pupa: Details unknown.

Adult: Not illustrated in UKMoths (check for update). The genitalia are not illustrated by the Lepidoptera Dissection Group (check for update).

Hosts in Britain:

Hosts elsewhere:

Time of year - larvae: July - August (British leafminers).

Time of year - adults: Unknown.

Distribution in Great Britain and Ireland: Widespread in England, Wales, Scotland and Northern Ireland including Cheshire, Derbyshire, Glamorgan, South Aberdeen and Stafford (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). See also British leafminers distribution map.

Also recorded in the Republic of Ireland (Karsholt and van Nieukerken in Fauna Europaea).

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 Austria, Bulgaria, Czech Republic, Danish mainland, Estonia, Finland, French mainland, Germany, Hungary, Italian mainland, Latvia, Lithuania, Norwegian mainland, Poland, Russia Central, Russia Northwest, Slovakia, Slovenia, Sweden, Switzerland, The Netherlands and Ukraine (Karsholt and van Nieukerken in Fauna Europaea).

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

Parasitoids in Britain and elsewhere: Unknown.