Favoritos de sean_c

Leafcutter Bee - Megachile macularis sharing nest cavity with wolf spider
Identified as Megachile Eutricharaea macularis on Bowerbird by Ken Walker: "An incredible sequence of images documenting something I could never have imagined."

Pacific Dune-Digger (Habropoda miserabilis)?

This was an impressive sight and sound! There were hundreds of males searching this area of open and moss-covered sand for emerging females. As I entered the patch of sand, careful not to step where bees were most actively searching, many males came up from just above the ground to swirl around me up to and just above my head; none landed on me and they soon went back to searching the ground. A few females were emerging and being engulfed in balls of males. These bee balls would roll around dynamically because of the bee movements and the sand topography. Some of the larger balls would break up into two or occasionally three smaller balls, but the second or third ball would break up soon after, presumably once the bees realized they were all males in that ball. In one spot where a female was emerging from sand covered by loose moss, it looked like several males were actively digging into the moss to reach her as she neared the surface. Occasionally a ball would reduce to one male and a female, perhaps because of my approach to take photos, but they would soon be discovered by additional males who joined them and formed another ball. Also, sometimes it looked like a male would fly in, land, and try to pull the female away from the other males already grasping her. As far as I could see in my photos that showed a female clearly, she seemed able to fend off some males by sticking her legs out as they approached by air, and to keep one or more attached males from mating with her by changing her posture and movements vigorously so they couldn't couple reproductively even though at least one and usually several males continued to grasp her. Nearly every open patch of sand I searched on a two-mile walk had at least some activity like this, although most of the spots had small groups of bees ranging from just a few to a few dozen bees; there was only one spot with hundreds of bees. Throughout the many nesting areas, including the largest one with hundreds of active bees, there were only a few new bee burrows with fresh sand aprons, suggesting that the females were still early in their emergence and activities.

Some additional photos that show a female as well as wing venation and other aspects of the morphology of these bees are in these other observations:
https://www.inaturalist.org/observations/205471848
https://www.inaturalist.org/observations/205471849
https://www.inaturalist.org/observations/205471850
https://www.inaturalist.org/observations/205471851
https://www.inaturalist.org/observations/205471852
https://www.inaturalist.org/observations/206799385 - includes a nest count
https://www.inaturalist.org/observations/206799376
https://www.inaturalist.org/observations/206799378
https://www.inaturalist.org/observations/206815217