Plant Parasites of Europe

leafminers, galls and fungi

Blasticotoma filiceti

Blasticotoma filiceti Klug, 1834


The mine, actually a larval cell, consists of a short corridor in the rachis, barely 2 cm in length -hardly longer than the larva itself-, usually at about a decimeter above the ground. The mine has an opening at the level of the rear end of the larva, and another one, much smaller, at the level of its head. Sometimes several larvae occur in the same rachis. Around the mine the rachis over a few cm has turned brownish black. The larva does not feed on the plant tissues, but on the sap that oozes into its cell. The larva produces at the rear opening a mass of froth, similar to the froth made by a spittle bug, but tougher, more resistant to drying out. Usually ants are attracted to the froth, because of its sugar content. The mine can be found easiest by looking for a combination of ants, a black discolouration of the rachis, and some withered leaf segments nearby.

host plants

Filicales, oligophagous

Athyrium distentifolium, filix-femina; Dryopteris filix-mas.

Also other ferns are mentioned sometimes (Polystichum; Onoclea struthiopteris; Pteridium aquilinum), but Lady-fern doubtless is the most important host plant.


Full grown larvae in end July – early August.


BE recorded (Verheyde ao).

NE recorded (de Meijere, 1911a).

LUX not recorded (Fauna Europaea, 2008).

distribution within Europe

From Sweden and Finland tot the Pyrenees, and from Ireland to the Ukraine (Bowdrey, 2008a; Fauna Europaea, 2008).


Greenish white with pale brown head (de Meijere).


Just like the “mines” of Cystiphora species with almost as much right one could consider these structures galls.


Birjukova & Novgorodova (2008a), Blank ao (1998a), Bowdrey (2008a), Buhr (1964a), Haris (2012a), Hering (1957a), Hoop (1983a), Knight & Howe (2006a), Liston (2007a), de Meijere (1911a), Mol (2017a, 2021a, 2022b), Pschorn-Walcher & Altenhofer (2006a), Redfern & Shirley (2011a), Robbins (1991a), Shcherbakov (2006a, 2008a), Taeger, Altenhofer, Blank, ao (1998a), Taeger, Blank & Liston (2006a), Mol (2017a), Taeger ao (1998a), Tomasi (2014a), Verheyde, Alberts & Mol (2018a).

Last modified 20.iv.2024