A new Megachile in the garden

It was a beautiful day on Sunday (18.7.2021) and I thought I would have a look at the bees on the flowers in the garden. I saw one on the Cosmos that I did not recognise.

Luckily I got a shot of the wing venation, and it is luck for me because it depends on the angle of the sun and how long the bee will stay in place.

The two sub marginal cells allowed me to confirm that it was a Megachile.

I would always like to go further but it is impossible to be precise from a photograph and I am not an entomologist, so I do not capture the bees for a closer look.

He looked like a male but I could not recall ever seeing him before but I had seen photographs on the internet.

This made me wonder if it was a Lithurgus chrysurus male. These are Mediterranean bees – but I am further north in the Charente Maritime.

They build their nests in dead, dry often rotting wood or even cow pats. Well, we have plenty of rotting wood left around the garden and certainly in the woods around us. Another feature is the extra long tongue which facilitates getting nectar from some plants such as the Centaurea. Cosmos is in the same family of Asteraceae so perhaps my bee is happy with my cosmos. He certainly had a long tongue.

So, I cannot be certain of my ID but he is very welcome in the garden and I am fascinated by his beautiful green eyes.

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A Megachile emerges

On the fourth of September last year I noticed a hole in my bee hotel had been beautifully sealed by carefully arranged sections of rose petals. (See Some Megachile).

On the 24 of May this year I noticed a hole had been chewed in the centre of it.

I could not resist removing the remains of the rose petals to get a better look.  A new little bee was making her way into the world.  However, it was 19.20 and domestic duties called and the light was fading for photographs.

It was 11.04 the next morning before I was able to get back to my bee and she seemed just to be waking up.

Seven minutes later and she was not  making an enormous progress.

Then two minutes later there is movement from the hole above her.

Now which one should I focus on?  The other one is larger and not the same species.  Very interesting but I do not want to lose my rose petal bee.

After a couple of minutes hesitation the big bee launches itself into the air.  Sorry about the blur but it was the best I could do.  I have no idea what species it was.

Back to my rose bee that has been emerging gradually for the last  34 minutes.  She seemed to have a considerable difficulty pulling herself through the little hole she had chewed in her leaf capsule that had been her home since last September.

Finally after watching and taking photographs of her for 35 minutes she emerges onto the outside of the log.

She paused momentarily before taking off.   After this first one, many others emerged from the same hole in the following few days, usually taking less time to exit than this first one.  Sometimes it looked as if the bee next in the queue was giving encouragement from behind because as one took off, another little head appeared at the hole.

However, I am not certain what species of leaf cutting bee she is.  Megachile centuncularis are well known for their use of rose petals which points me in this direction.  It is a common bee and I have seen bees looking like Megachile centuncularis on the bee box last year.

Could this be Mummy emerging from another hole in the log on the 26 August last year?

I base my identification of the bees I saw filling the holes last August on Steven Falk’s wonderful photographs and information

, he says females can be distinguished from some other British species by the bright orange pollen brush that remains orange haired to its tip (black-haired at tip in some others).

Well, even if I cannot be 100 percent sure of my French bees at least I can say I breed beautiful bees!

 

Some Megachiles

Megachiles collect their pollen on brushes under their abdomen.  The colour of these hairs can often be used to help identify the species.

But as with anything else used in identifying bees – it has its limits.  The underside of the bee can look the same colour as the pollen when it is heavily loaded.

That’s a good load of pollen!

They are commonly know as leaf cutter bees as they choose already existing holes and line them with leaves to lay their eggs with a pollen and nectar store before sealing the cell with more leaves.  They choose leaves that can be manipulated easily from trees such as lilac, ash or cherry or flower leaves such as roses or even rose, poppy or geranium petals.

5 September 2013

You can see her determination to fit this piece where she wants it.  This shot was taken in my home-made bee hotel and I recommend trying one out as they are fascinating bees to watch.

This one was a late riser.  Perhaps she had had a busy building job the previous day.  It was 9.49 a.m. on the 26 August 2013 and she was still asleep with the last leaf she had brought home acting as a blanket.

On the 4 September 2013 one of the bees finished off their nest with rose petals – class!

I’m going to go for a photographic ID (i.e. not an expert one) and say that this is Megachile centuncularis on my dahlia at the beginning of October 2013.  These are the bees I believe are nesting in my bee hotels.  In addition, the wing venation checks out with the images I’ve seen.

But there are other bees that look like Megachile around, like this tiny black one on Centaurea nigra in early August.

And this one with green eyes on Bird’s Foot Trefoil in late June (I think probably, Megachile leachella).  Although these last two may be tricking me with their ventral pollen brushes as Osmia and Lithurgus bees have ventral pollen brushes too.

But I’m as satisfied as I can be that she is Megachile centuncularis.