Blasticotoma filiceti Klug, 1834

mine

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.

phenology

Full grown larvae in end July – early August.

BENELUX

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).

larva

Greenish white with pale brown head (de Meijere).

notes

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

references

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), 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).