Tip of frond mined by Chirosia betuleti on Dryopteris filix-mas Image: Willem Ellis (Bladmineerders van Europa)

Gall-former: The larva mines the leaves and stems. Tip of frond rolled upwards into a loose, conspicuous mop-head involving many pinnae; inside a white larva mines along rachis causing it to coil (Redfern et al. (2002: 288, fig. 105).

Larva in the leaf tip, that is strongly contorted. An elongated white egg shell is visible at the centre of the mass (Bladmineerders van Europa).

Chirosia betuleti is the only Chirosia species to form galls (Griffiths).

Larva: The larva is described by de Meijere (1911), who gives an account of the biology, and Ellis (Bladmineerders van Europa).

Puparium: Details unknown.

Comments: Ackland in Chandler (1978) did not indicate whether his host record was British or Foreign and is therefore included under 'Hosts in Britain' and 'Hosts elsewhere'.

Hosts in Britain:

Hosts elsewhere:

Time of year - mines: End May - early July (Bladmineerders van Europa).

Time of year - adults: Unknown.

Distribution in Great Britain and Ireland: Widespread in the south of Britain; Cornwall, Wiltshire, Worcester, Hants, Norfolk, Merioneth (Mike Ackland, pers. comm.), Warwickshire (Oversley Wood) (Robbins, 1991: 21). Berkshire, Cardiganshire, Cheshire, Denbighshire, East Norfolk, East Suffolk, Easterness, Elgin, Flintshire, Herefordshire, Merionethshire,Mid Perth, Mid-west Yorkshire, Montgomeryshire, North Lincolnshire, North Somerset, Oxfordshire, Shropshire, South Devon, South Hampshire, South-west Yorkshire, Stafford, Surrey, West Gloucestershire, West Kent, West Suffolk and Worcestershire (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).

Also recorded in the Republic of Ireland (Michelsen, 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: The Netherlands (Bladmineerders van Europa), Czech Republic, Denmark, Finland, ? French mainland, Germany, Italian mainland, Norwegian mainland, Poland, Russia - North and Northwest, Slovakia, Spanish mainland and Sweden (Michelsen, 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.