Mikiola fagi (Hartig, 1839)
on Fagus
Fagus sylvatica, Hungary, Budapest, János-hegy © László Érsek
two galls
underside of a galled leaf
detail
opened gall
larva
Fagus sylvativa, Bussum: at the left the gall of a male, at right of a female larva
Fagus sylvatica, Elspeet, Kasteel Staverden, 18.vi.2019 © Hans Jonkman: unusual cluster of female galls
Fagus sylvatica, Tilburg
underside
the wall of the very hard gall consists of several layers of high, glassy cells, with an inner linning of much smaller, greenish cells
the floor of the gall room ….
…. is covered by loose, swollen, cells; probably thy form the food for the larva
the gall grows much faster than the larva; therefpore a full grown gall initially contains a minute larve, but later a much larger one, like here
an alaready moribund larva and its small parasitoid
an adult parasitoid, that still was in a shriveled gall
also the occupant of this gall ended badly
gall
When the larva is full grown the gall drops to the grond, and the larva closes the opening with silk. The larva hibernates in the gall and pupates in spring.
host plants
Fagaceae, monophagous
Fagus orientalis, sylvatica, x taurica.
Very rarely also on Castanea.
larva
Fagus sylvatica, Tilburg; larva, ventral
spatula and head of the larva
prosternum with spatula (from Möhn, 1955a)
pupa
Fagus sylvatica, Roggebotsebos © Arnold Grosscurt
notes
The species is abundantly common in the Netherlands. It is the more surprising that, as Redfern & Shirley write, the species seems to have gone extinct in the UK.
Galls mainly high up in the canopy (Kampichler & Teschner, 2002a).
The larvae may be killed within their gall by a strong development of the endophytic fungus Apiognomonia errabunda.
references
Abras, Fassotte, Chandelier & Cavelier (2008a), Barnes (1951a), Béguinot (2001c, 2002e,g, 2005a, 2006a, 2007b, 2012a), Bellmann (2012a), Blanes-Dalmau, Caballero-López & Pujade-Villar (2017a), Bruun (2015a), Buhr (1964b), Cilbircioğlu & Ünal (2009a), Cogolludo (1921a), Coulianos & Holmåsen (1991a), Dauphin & Aniotsbehere (1997a), Dziurzynski (1961a,b), Gagné (2010a), Groom (2011a), Hellrigl (2006a), Houard (1908a), Ilie & Marinescu (2011a), Kampichler & Teschner (2002a), Kieffer (1901a), Kollár (2011a), Koops (2013a), Lambinon, Carbonnelle & Claerebout (2015a), Lambinon & Romain (2009a), Lambinon, Schneider & Feitz (2001b), Lehmann & Hannover (2016a), Mirumian (2011a). Möhn (1955a), Nieves Aldrey (1998a), Pujade i Villar (1990a), Redfern & Shirley (2011a), Roques, Cleary, Matsiakh & Eschem (2017a), Roskam (2009a), Roskam & Carbonnelle (2015a), Seidel (1957a), Simova-Tošić & Skuhravá (2001a), Simova-Tošić, Skuhravá & Skuhravý (1999a, 2000a, 2004a, 2007a), Skrzypczyńska (2007a), Skuhravá (2006a), Skuhravá, Bayram, Çam ao (2005a), Skuhravá, Karimpour, Sadeghi ao (2014a), Skuhravá & Skuhravý (1988a, 1992b, 1994a, 1997a,b, 1999a,b, 2005c, 2006a, 2007a, 2008a, 2009b, 2010a), Skuhravá, Skuhravý, Blasco-Zumeta & Pujade-Villar (2006a), Skuhravá, Skuhravý & Buhr (2013a), Skuhravá, Skuhravý, Dauphin & Coutin (2005a), Skuhravá, Skuhravý, Dončev & Dimitrova (1991a, 1992a), Skuhravá, Skuhravý &; Hellrigl (2001a), Skuhravá, Skuhravý & Jørgensen (2006a), Skuhravá, Skuhravý & Massa (2007a), Skuhravá, Skuhravý & Meyer (2014a), Skuhravá, Skuhravý & Neacsu (1972a), Skuhravá, Skuhravý, Skrzypczyńska & Szadziewski (2008a), Stănescu (2009a), Tomasi (2003a, 2014a), Unal & Akkuzu (2009a).