Lasioglossum sexnotatum?

[Jann Wuebbenhorst]

This Lasioglossum was photographed on 03rd Apr 2018 in a sandy garden in the eastern part of Lower saxony (Germany), visiting Eranthis hyemalis; size about 11 mm.
I know Lasioglossum species are often indiscernible on field photos, but maybe the detailed photos can help in this case.
I add some details of tergites 1 and 2, the head, the mesonotum, the mesopleuron and the upper part of the propodeum.

L. sexnotatum is supposed to be very rare in Lower Saxony, but in some adjacent federal states of Germany it is not that rare.

best wishes,
Jann

[Jann Wuebbenhorst]

some more photos

[Darek Ogrodnik]

Sexnotatum seems correct but I'm not certain about it.

[Jann Wuebbenhorst]

Many thanks for your valuation, Darek.
Is it possible to say which other species must be considered?
Here in Northern Germany, there are not as many bee species as in Southern Germany, Switzerland, Austria or eastern european countries.

[Darek Ogrodnik]

It also might be L. costulatum

[Jann Wuebbenhorst]

Thank you very much again, Darek.
L. costulatum should appear about 4 weeks later than L. sexnotatum and not before the beginnung of May, following Amiet et al. (2001). And L. costulatum was thought to be extinct in Lower Saxony, but since 2005 there were three new records.
I have observed Lasioglossum looking like this last year visting Asparagus and Papaver, but not yet Campanula.
So I think overall L. sexnotatum (though also rare in Lower Saxony) is more likely - but I cannot be sure.
I hope next time I manage to collect one of these.
best wishes, Jann

[Christian]

You cannot be sure by this photo, because all important characters (propodeum, punctation of tergite I etc.) are not visible.

Best wishes, Christian

[Jann Wuebbenhorst]

I think the punctuation of Tergit 1 is visible in photo 9 (base sparsely punctate, even and shiny between the punctures; apical depression densely punctate) - for me it looks the same as in this photo by Steven Falk:
https://www.flickr.com/photos/63075200@N07/15401260711/in/album-72157647924134795/
The upper area of the propodeum is visible in nos. 4 and 5.
So I thought it was worth a try