Blue-banded Bee loves Penstemon "Sour Grapes"

Yesterday, a Blue-banded Bee was noisily buzzing around the Penstemon "Sour Grapes" near my front verandah. These Bees are native to Australia, and Asian countries.

The blue colour of the bee is not obvious.

It varies between males and females, apparently.

There is a faint blue colour on the"white bands"

But it is not obvious in these photos.
It is more obvious in this photo courtesy of Peter Chew's
Brisbane Insects and Spiders website

It is well reported that these Bees have an affinity for blue or purple flowers. 

That certainly holds true for this individual Bee.

The other thing of interest to me was that Bee's flight.

It is described as a "dart-and-hover flight pattern",

This Bee would land on the floral tube of the Penstemon,
and then climb inside the flower.
Then it would back out, and quickly fly to another flower.

This Bee is a noisy flier
and the tone changes as it varies its flight pattern.
It is reported to be a non-aggressive Bee.