Ceutorhynchus napi Gyllenhal, 1837
rape stem weevil
on Brassicaceae

Brassica napus, Hungary, Mosonmagyaróvár © László Érsek: larva boring in the stem

th stem swells and tears open (picture taken on April 9) …

… and becomes seriously destroyed (April 22)
mine
The larva essentially is a borer in petiole or stem. Some larvae (“many”, according to Hering [1957a], “1-3”, according to Scherf [1964a]) live there together in a cavity. At that point the stems is galled and swollen. From there sometimes a larva strays into the leaf blade. Pupation in the soil.
host plants
Brassicaceae, oligophagous
Alliaria petiolata; Barbarea intermedia; Brassica napus, oleracea, rapa; Raphanus raphanistrum; Sinapis arvensis; Sisymbrium altissimum, officinale.
Occasionally also on Reseda
phenology
Larvae in April-July (Scherf, 1964a).
BENELUX
BE observed (Curculionidae.be, 2010a).
NE observed (Fauna Europaea, 2007; Heijerman, 1993a).
LUX not observed (Fauna Europaea, 2007).
distribution within Europe
From Denmark and Poland tot the Iberian Peninsula and from France to Bulgaria; not in the British Isles (Fauna Europaea, 2007).
larva
Scherf (1964a).
references
Balalaikins (2012a), Buhr (1964b, 1965a), Compte (1981a), Delbol (2008a, 2013a), Dieckmann (1972a), Günthart (1949a), Heijerman (1993a), Hering (1957a), Houard (1908a), Rheinheimer & Hassler (2010a), Scherf (1964a), Tomasi (2014a), Vorst (2010a), Yunakov, Nazarenko, Filimonov & Volovnik (2018a).