Evening Primrose species, Oenothera sp., Onagraceae.
Southern Okanagan Valley.
Bisexual flower, with 4 long, reflexed sepals, open evening to early morning, have bright a nectar-guide pattern visible only under ultraviolet light.
1: partially dissected blossom of a cultivated variety of Evening Primrose, shows some very cool aspects of this blossom—the long style and cruciform stigma and the incredible pollen that is shed in stringy clumps from the long anthers. Also, at the base of the petals, nectar visibly glistens between the stamens.
2: Drawing page showing a dissected blossom and the triangular pollen grains with their viscin threads. The grains themselves are very large (>100μm), and must be a problem for bees to negotiate.
3: An Agapostemon bee actively collecting pollen inside the partially closed petals. You can see the little triangular pollen grains on her leg.
4: A blurry shot of 2 Agapostemon bees in one blossom. I was highlighting the pollen threads instead of the bees.
5: A leafcutter just taking off, not only her belly covered in pollen, but the rest of her too.
6 & 7: Two images of the small native, red-listed Oenothera pallida.
This small species of Evening Primrose has a specialist forager, the subgenus Sphecodogastra of Lasioglossum which is specifically adapted for foraging on this blossom - big ocelli to help them fly at dawn and dusk when the light is low, and with specialized scopal hairs too to help them collect the stringy pollen.
Image 7 has an ant diving into the tiny pool of nectar.
It was great to see both species of this Evening Primrose. Glad that I got to document bees on the larger variety at least! #botanicaldrawing #pollinatorsandflowers #pollinatorweek2018 #oenathera #oenatherapallida #okanaganvalley #florilegium #pollencolours #pollencollectors - 8 hours ago