Sept 13th – Identification Progress and answers to guess that structure!

Hi Everyone,

I do not have that much exciting information to share, hence the decrease in posts. We are now over 21,000 bees identified to at least genus, with 12,000 of those finished with species level IDs. There is still plenty of work left to do, but we are making progress. I will also be out the next week and a half, so there will once again be a probably three week delay in the next blog post since I won’t be making any progress while I am out.


Interesting bees:

Most bees have somewhat wide heads, as shown by this Pseudopanurgus specimen below.

Pseudopanurgus are a group of mostly black bees that are generally uncommon, but most likely to be found in the fall on plants in the family Asteraceae. They have somewhat wide heads. They also have distinct facial fovea, which helps identify that they are in the family Andrenidae.

In direct comparison, perhaps our skinniest bees are in the genus Chelostoma.

Chelostoma bees are most often found in the spring. They are in the family Megachilidae, so they carry pollen on their stomach instead of their legs. They also are so distinctively skinny that it is hard to confuse them for the other Megachilidae.


Guess that structure:

No one guessed correctly for this structure, which is not that surprising.  They are the tibial spurs on the inner part of the legs! They are thought to help the bees brush pollen off their body to then load it onto their legs and help with general cleaning. Different species of bees have different tibial spurs and sometimes the shape is diagnostic for species level ID.

This is best shown in the Hook-spurred Longhorn Bee, Eucera hamata. A few people got these large bees in their samples, though they are not nearly as common as bumble bees.

The tibial spurs are on the inner side of the legs, so they are not often seen in most photographs. You have to move the specimen just right to be able to see the spurs.

In Eucera hamata, the tip of the spurs are distinctly hooked at the tip, which helps separate them from other Eucera species.


All for now,


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