Posted by Juergen Peters on 07-05-2022 18:38
#1
Hello,
are these two
Bibio males (ca. 8 mm) the same species? Yesterday at housewall and at a hedge near forest (northwest Germany).
Edited by Juergen Peters on 09-05-2022 23:11
Posted by eklans on 08-05-2022 07:56
#3
Hi Jürgen, yes - these are the same species - and I think it's B. johannis.
Posted by Juergen Peters on 09-05-2022 02:32
#4
eklans wrote:yes - these are the same species - and I think it's B. johannis.
Thanks, Eric! But are you sure?
Bibio johannis normally flies in March and early April here (I have seen some in the first April week). After a while with no Bibionids there are now several other species flying.
Posted by eklans on 09-05-2022 07:55
#5
Hi Jürgen, I
think they are, based on this information (the dark stripe on tibia III is visible on the 2nd image):
on male Bibio johannis:
Een veldtabel voor de inheemsezwarte vliegen (Bibionidae) door Theo Zeegers, 1997
mid April - mid May, antennae: 9 segments, metatarsus slightly thickend, approx. length = width x 3
(excerpt translated by eklans)
BIBIONIDAE DE LA FAUNE BELGE, Jan Verbeke, 1971
wings hyaline, strong brown stigma
flagellum 7 segments
body black, black hairs - including occiput
tibia III yellow, gradually thickened from base to tip,
rear surface with brown stripe
metatarsus III thickend
legs I & II predominantly reddish brown to brownish
tibia II yellowish - legs sometimes completely yellowish
(excerpt translated by eklans)
Suomen karvasääsket ja maasääsket (Diptera, Bibionidae ja Pleciidae), Antti Haarto, 2012
Antennae with 9 segments. Colour of hind femora
varies from totally yellow to largely dark brown. Hind
tibia yellow and evenly broadened towards its apex.
Hind tibia with dark stripe of sensillae
Dark specimens have black femora and brown tibia
and therefore the dark stripe of sensillae does not
differentiate. Tarsi yellow.