Heterarthrus fiora Liston, 2019

Acer pseudoplatanus, Nieuwendam: vacated mine
mine
A large upper-surface (often almost full depth) blotch, without a trace of an initial corridor, beginning in the very tip of a leaf segment. The full grown larva spins itself a disc shaped cocoon within the mine. Just before, it has made with its mandibles a circle of perforations in the upper epidermis. The the cocoon is formed, attached to the upper epidermis, and the larva becomes immobile. The perforated circle of epidermis starts to dry, warps, and finally becomes detached from the surrounding tissue and drops to the ground (Altenhofer, 1980b; Altenhofer & Zombori, 1989a). Th resulting excision has a diameter of about 7 mm, and is best seen when the leaf is held against the light.
host plants
Sapindaceae, narrowly (?) monophagous
Acer pseudoplatanus.
In my experience, and also according to Altenhofer & Zombori (1987a), Robbins (1991a), and Späth & Liston (2003a) this is the only host plant. However many authors, also modern ones, report the species from A. campestre. The statement by Hering (1957a) that the species in Sweden is also common on A. platanoides certainly must derive from confusion with Heterarthrus flavicollis (Gussakovskij) (Liston, 1993a). Buhr (1941a) reared H. fiora from the small leaves of Acer monspessulanum. Matošević ao (2009a) mention Acer obtusatum as the host plant.
phenology
Larvae in June-July (Hering, 1957a).
BENELUX
BE recorded (Ellis, Sinnich).
NE recorded (van Ooststroom, 1976a).
LUX recorded (Chevin, Ellis & Schneider, 2011a).
distribution within Europe
From Sweden tot the Pyrenees bd Italy, and from Ireland to the Ukraine (Fauna Europaea, 2008).
larva
Like in all Heterarthrus species the thoracic feet are reduced to small stumps; See also Ritzema Bos (1882a).
synonyms
Heterarthrus aceris auctorum. A study by Liston, Mutanen & Viitasaari has shown that the description of Heterarthrus, Phyllotoma, aceris Kaltenbach, 1856 actually applies to Heterarthus leucomela.
parasitoids, predators
notes
The biology is extensively described, and larva and pupa illustrated, by Ritzema Bos (1882a). He remarks that the larvae in the fallen cocoons still are sufficiently active to make their cocoons, with attached leaf disks, jump for 5 – 10 mm height. The species is fully parthenogenetic (Schedl, 2006a).
The mines of the Central European Heterarthrus leucomela resemble those of fiora, but the cocoon does not drop out of the leaf.
references
Ahr (1966a), Altenhofer (1980b, 2003a), Altenhofer, Hellrigl & Mörl (2001a), Altenhofer & Zombori (1987a), Beiger (1979a), Blank ao (1998a), Boevé, Peter, Jacobs, ao (2009a), Buhr (1933a, 1941a, 1964a), Chevin, Ellis & Schneider (2011a), Drăghia (1971a), van Frankenhuyzen & Houtman (1972a), van Frankenhuyzen Houtman & Kabos (1982a), Haase (1942a), Hering (1934b, 1936b, 1957a), Hoop (1983a), Huber (1969a), Kollár & Hrubík (2009a), Kvičala (1938a), Liston (1993a, 1995b, 2006a), Liston, Knight, Heibo, ao (2012a), Liston, Mutanen & Viitasaari (2019a), Lorenz & Kraus (1957a), Maček (1999a), Matošević, Pernek, Dubravac & Barić (2009a), Nowakowski (1954a), van Ooststroom (1976a), Pieronek (1962a), Popescu-Gorj & Drăghia (1968a), Pschorn-Walcher & Altenhofer (2000a), Ritzema Bos (1882a), Robbins (1991a), Savina, Liston, Boevé, ao (2013a), Schedl (2006a), Scobiola-Palade (1974a), Skala & Zavřel (1945a), Sønderup (1949a), Späth & Liston (2003a), Stritt (1952a), Surányi (1942a), Taeger, Blank & Liston (2006a), Taeger ao (1998a), Tomov & Krusteva (2007a), Ureche (2010a), Wahlgren (1944a).