Plant Parasites of Europe

leafminers, galls and fungi

Cyanus segetum


synonym: Centaurea cyanocephala, cyanus

organparasitic modestagenotetaxonomic groupparasite
seedsvagrantLygaeidaeMegalonotus sabulicola
flowerborerTephritidaeChaetorellia australis
flowerborerTephritidaeTerellia colon
flowergallTephritidaeAcanthiophilus helianthi
rootscaleEriococcidaeAcanthococcus cingulatus
leafhiddenDepressariidaeAgonopterix laterella
leafhiddenDepressariidaeAgonopterix kaekeritziana
flowerhiddenThripidaeFrankliniella intonsa
unknownborerlarvaApionidaeCeratapion basicorne
leafvagrantsummer generationAphididaeAphis fabae fabae
leafdownPeronosporalesBremia centaureae
leafvagrantsummer generationAphididaeAphis fabae
systemicvagrantAphididaeProtaphis terricola
systemicborerAnguinidaeDitylenchus dipsaci
fruitgallTephritidaeUrophora quadrifasciata
flowerborerTephritidaeChaetostomella cylindrica
flowerborerTephritidaeTrupanea stellata
flowergalldoubtfulTephritidaeUrophora aprica
leafdownErysiphalesGolovinomyces depressus
leafdownErysiphalesGolovinomyces montagnei
leafdownErysiphalesPodosphaera xanthii
leafdownPeronosporalesBremia lactucae
leafminerAgromyzidaePhytomyza spinaciae
leafminerDepressariidaeAgonopterix subpropinquella
leafpustuleaeciaPuccinialesPuccinia caricis-montanae
leafpustuleuredinia teliaPuccinialesPuccinia cyani
leafpustuleuredinia teliaPuccinialesPuccinia jaceae
stemborerAgromyzidaeOphiomyia curvipalpis
root collarborerApionidaeCeratapion penetrans
rootgallMeloidogynidaeMeloidogyne hapla
leafvagrantAphididaePaczoskia obtecta
leafvagrantsummer generationAphididaeBrachycaudus helichrysi
flowervagrantAphididaeUroleucon jaceae


the part of the plant that most conspicuously is hit by the parasite

all buds: both flower buds and leaf buds
flower: also inflorescence
leaf: also needle, phyllodium, petiole
leaf bud: also unfolding young leaf
fruit: also seed
root: also root stock, runners
root collar: also the lowest part of the stem
stem: also culm, the lower part of the peduncle, in grasses also leaf sheath
systemic: the entire above-ground plant.


borer: larva living internally, almost no outwards signs
down: 0.5-2 mm high fungal down
film: very thin cover of fungal tussue
gall: swelling and/or malformation
grazer: feeding at the outside of the plant
leaf spot: discoloured, often ± necrotic, generally not galled, sign of a fungus infection
miner-borer: larve initially makes a mine, lives as a borer later
pustule: plug of fungal tissue, generally brown-black and < 2 mm
stripe: longitudinal line of fungal tissue in a grass leaf
vagrant: (aphids, mites) living freely on the plant, at higher densitiy causing malformations.


To filter the table above, add a text to the search field (top right of the table).
To sort a column click on an arrow after the column name (both ascending and descending).
Sort multiple columns with Shift + click on the arrows.


The host plant spectre of a parasite is rarely known exhaustively; this applies in particular at the species level. It is advisable therefore to check at least also the list of all parasites of this genus.


Last modified 5.iv.2022