Tanysphyrus lemnae (Paykull, 1792)
duckweed weevil
on Lemna, etc.
Spirodela polyrhiza, Belgium, prov. Antwerp, Laakdal,de Roost, 5.ix.2021 © Carina Van Steenwinkel: occupied mijn
larva, about to swim to a new leaf
mine
In duckweed the female eats a hole in the upper side, deposits an egg, and covers it with frass. The larva completely eats the content of the thallus, then moves, swimming if necessary, to other thalli that also ware mined out. Frass in thick lumps. Pupation in the soil or among water plants washed ashore.
The mine in Calla is a fan of strongly branched corridors, radiating from the leaf base. This very different aspect has originally been described as T. callae.
host plants
Araceae, oligophagous
Calla palustris; Lemna minor; Spirodela polyrhiza.
BENELUX
BE recorded (Curculionidae.be, 2010).
NE recorded (Vorst, 2010a).
LUX not recorded (Fauna Europaea, 2009).
distribution within Europe
From Fennoscandia to the Pyrenees, Sardinia and Italy, and from Britain to Poland; also Bulgaria (Fauna Europaea, 2009); introduced in North America.
synonyms
Tanysphyrus callae Voss, 1943.
references
Ahr (1966a), Dieckmann (1983a), Hering (1957a), Pešić (2000a), Rheinheimer & Hassler (2010a), Sønderup (1949a), Urban (1922b, 1926a), Vorst (2010a), Yunakov, Nazarenko, Filimonov & Volovnik (2018a), Zoerner (1969a).