Phyllocnistis unipunctella (Stephens, 1834)
poplar bent-wing
on Populus
Populus nigra, Hungary, Budapest © László Érsek
larva in the mine
larva, ventral

Populus x canadensis, Nieuwendam

Populus nigra cv. ‘Italica, Belgium, prov. Liège, Sclessin: cocoon, always at the leaf margin © Jean-Yves Baugnée

Populus nigra cv. ‘Italica, Belgium, Liège: often the larvae are exposed to the glaring sun, with no other protection the the plant’s cuticle © Jean-Yves Baugnée
mine
Very long, broad, epidermal corridor that winds in dense loops over the upper side of the leaf without crossing itself. Frass in a continuous, extremely vague central line. The mine ends at the leaf margin, where the corridor is slightly widened, and in which some silk is deposited. When this dries the the leaf margin somewhat folds over this pupal chamber, since it is here that pupation takes place.
The mine has a strong resemblance to the trail of dried mucus left by a small snail, which has given the mine its Dutch name of “snail-trail mine”.
host plants
Salicaceae, monophagous
Populus balsamifera, x canadensis, carolinensis, euphratica, gileadensis, nigra & cv. ‘Italica’, simonii, suaveolens, trichocarpa.
Records of P. alba probably are due to confusion with Phyllocnistis xenia; records P. tremula hebben may in fact refer to Ph. labyrinthella.
phenology
Until perhaps the year 2000 there were two generations, with larvae in June – July and August – September (Emmet,1985b). Currently, there are at least three generations, the first one already in April; see note below.
BENELUX
BE recorded (Phegea, 2009).
NE recorded (Kuchlein & de Vos, 1999a; Microlepidoptera.nl, 2009).
LUX recorded (Fauna Europaea, 2009).
distribution within Europe
All Europe (Bond, 2001a; Fauna Europaea, 2009).
larva
pupa
synonyms
Phyllocnistis suffusella (Zeller, 1847).
parasitoids, predators
notes
recent studies have demonstrated the existence of two types of larvae. Those of the first generation mine already in April, predominantly at the underside of the leaves; these larvae have in their third instar an unpigmented prothoracic plate. The larvae of the subsequent second and third generation mine the upper side of the leaves; in their third instar these larvae have the prothoracic plate darkly pigmented (Jordan, Langmaid & Doorenweerd, 2016a).
references
Abras, Fassotte, Chandelier & Cavelier (2008a), Amsel & Hering (1931a), Arru (1996a), Bengtsson & Johansson (2011a), Bond (2001a), Braggion (2013a), Buhr (1935b, 1936a, 1964a), Buszko (1981a, 1992b), Charles, Nef, Allegro, ao (2014a), Corley, Maravalhas & Passos de Carvalho (2006a), Corley, Rosete, Gonçalves ao (2016a), Csóka (2003a), Delplanque (1998a), Deutsch (2017a), Deutschmann (2008a), Drăghia (1968a, 1971a, 1972a, 1974a), Emmet (1985b), van Frankenhuyzen & Freriks (1969a), van Frankenhuyzen & Houtman (1972a), van Frankenhuyzen Houtman & Kabos (1982a), Grandi (1931a, 1933a), Haase (1942a), Hartig (1939a), Hering (1923a, 1930b, 1957a), Huber (1969a), Huemer (1986b), Jaworski (2009a), Jordan, Langmaid & Doorenweerd (2016a), Kasy (1965a), Klimesch (1950c, 1957a), Kollár (2007a), Kollár & Hrubík (2009a), Kuchlein & Donner (1993a), Kuchlein & de Vos (1999a), Kvičala (1938a), A & Z Laštůvka (2011a), Lhomme (1934d), Lüders (1990a), Maček (1999a), Martynova (1955a), Matošević, Pernek, Dubravac & Barić (2009a), Parenti & Varalda (2000a), Patočka (2001a), Patočka & Turčáni (2005a), De Prins (1998a, 2016a), Robbins (1991a), Sakaltaş Ariyak & Tüzün (2014a), Schmid (2019a), Schütze (1931a), Sefrová (2005a), Skala (1951a), Sønderup (1949a), Stammer (2016a), Starý (1930a), Szőcs (1977a, 1978a, 1981a), Ureche (2010a), van Wielink (2020a), Zoerner (1969a).