The velum and strigilis

I didn't know about the foreleg apparatus bees use to clean their antennae. Until I ran into the value of the character in the DiscoverLife Osmia key. There is an excellent description in NATURAL HISTORY AND ECONOMY OF THE BEES Indigenous to the British Isles. W. E. SHUCKARD, 1866.

...on the anterior tibiæ of all the bees, there is, within, a small velum, or sail, as it has been called; this is a small angular appendage affixed within the spur by its base. At the base of the palmæ of the same legs, and opposite the play of this velum, there is a deep sinus, or curved incision, the strigilis, called thus or the curry-comb, from the pecten, or comb of short stiff hair which fringes its edge. Upon this aperture the velum can act at the will of the insect, and combined they form a circular orifice. The object of this apparatus is to keep the antennæ clean, for the insect, when it wishes to cleanse one or the other of them, lays it within this sinus of the palma, and then, pressing the velum of the spur upon it, removes, by the combined action of the comb and the velum, all excrescences or soilure from it, and this process it repeats until satisfied with the cleanliness of the organ.

My photo below, and a far more elegant drawing from an 1878 publication of the British Bee Journal (along with additional flowery 19th Century discussion of pollen collection).

Publicado el 24 de agosto de 2022 a las 11:36 PM por cappaert