Posted by
Sundew on 03-05-2020 17:37
#1
Hi,
On May 22, 2019, I saw several couples of
Tephritis on
Crepis biennis. Though
T. conyzaefoliae and
T. crepidis are difficult to tell apart, I hope the hostplant speaks for the latter! The location is southwestern Germany, about 20 km west of Stuttgart.
Thanks for help, Sundew
#4
Be aware that there is another Tephritis on another Crepis.
Where I live they are sitting next to each other on a grassland, T. crepidis on C. biennis and T. matricariae on C. taraxacifolia.
Apart from the size I'm not able to separate the two Crepis sp, so I need the fly to recognise the plant.
Ben
Posted by
Sundew on 05-05-2020 14:54
#5
That's funny - plant identification via fly species! (
Crepis taraxacifolia has meanwhile again been degraded to a subspecies of
C. vesicaria.) I learnt, however, that the two taxa prefer not exactly the same habitat.
C. v. subsp.
taraxacifolia seems to be more ruderal and grows on drier sites (on slopes, walls...), whereas
C. biennis is a typical constituent of fertile meadows. According to the species composition of the meadow where I saw the flies, I suppose it was sown, and
C. biennis is a component of commercial seed mixtures. Nevertheless I will look more closely to the species characters this year to avoid any confusion.