Plant Parasites of Europe

leafminers, galls and fungi

Etainia louisella

Etainia louisella (Sircom, 1849)

maple-seed pigmy

Etainia louisella mine on Acer campestre

Acer campestre, Belgium, prov. Liège, Liège, canal de l’Ourthe © Jean-Yves Baugnée

Etainia louisella: larva

Acer campestre, België, prov. Namur, Vierves-sur-Viroin © Stéphane Claerebout: larva, ventral view


Oviposition on the wing of a key (“samara”). The larva makes a short superficial corridor (sometime only the egg is visible) running towards the seed. Finally the seed is eaten out. Attacked fruits remain on the plant (Johansson ao, 1990a).

host plants

Sapindaceae, monophagous

Acer campestre, tataricum.


Mining larvae in June-Junly (Alders, 2004a); Emmet (1983a) speculates that in the UK sometimes two summer generation occur.


BE after 2004 recorded in all provinces (Phegea, 2004).

NE recorded (Alders, 2004a).

LUX not recorded (Fauna Europaea, 2007).

distribution within Europe

From the UK to the Ukraine, and from Denmark to Italy (Fauna Europaea, 2007).


In a brownish cocoon, often on the stem.


Ectoedemia louisella; Stigmella, Etainia, Obrussa, sphendamni (Hering, 1927).


The larvae that hatch in autumn consume a number of buds for the next year from the inside out. Only the next spring this non-mining hibernating generations pupates (Emmet, 1984a).


Alders (2004a), Bengtsson (2008a), Borkowski (1969a), Černý (2001a), Demyanenko, Bidzilya & Karolinskiy (2021a), Emmet (1983a), Hering (1957a), Huisman, Koster, van Nieukerken & Ellis (2009a), Huisman, Koster, van Nieukerken & Ulenberg (2005a), Jäckh (1951a), Johansson ao (1990a), Kasy (1983a), Kuchlein & Donner (1993a), Kuchlein & de Vos (1999a), Kurz (2016a), Laštůvka & Laštůvka (1997a, 2015a), Lepiforum (2023), Maček (1999a), Navickaitė, Diškus & Stonis (2014), van Nieukerken (1986a), van Nieukerken, Laštůvka & Laštůvka (2006a), Robbins (1991a), Sefrová (2005a), Skala (1939a), Skala & Zavřel (1945a), Snyers (2008b), Sønderup (1949a), Stonis, Navickaitė, Rocienė ao (2013a), Szőcs (1977a, 1978a, 1981a), Vos (2017a), Wieser (2004a).

Last modified 4.viii.2023