Andrena humilis?

[JRsbugs]

Hi,

It looks like it! I found it after it had apparently climbed out of my pond, quite wet. I took it to a leaf to dry off, she was quite big I would say ~14mm.

I have a sand path with a new big nest mound on it with a large hole in the middle which is not the same as A. clarkellas nest, there's two of those nesting there. I have Hieracium and there's usually plenty of dandelions around.

Janet

[Jason Green]

Morning Janet,

What a nice garden insect that would be! Alas, the pronotal shape doesn't fit humilis in my mind - it also seems to be a touch too big. As is frequently the case, details of the propodeum, punctuation and clypeal/mandibular information is required to really investigate the possibilities of what it may be.

Something like Andrena synadelpha may be more 'fitting'.

Take care,

Jason

[JRsbugs]

Originally Posted by Jason Green

Morning Janet,
Something like Andrena synadelpha may be more 'fitting'.

Take care,

Jason

I would disagree with that Jason.

Andrena synadelpha:

http://www.natureconservationimaging...synadelpha.jpg

Please note that these on Flickr are from a barcoding scheme..

BC_ZSM_HYM_01425 Andrena synadelpha | Flickr - Photo Sharing!

Andrena humilis:

http://www.natureconservationimaging...na-humilis.jpg

Note the 'pronotal shape'

BC_ZSM_HYM_00232 Andrena humilis | Flickr - Photo Sharing!

There may be something I'm missing as I don't have keys, but from what I can see it looks very much like A. humilis.

[Matt Smith]

Andrena humilis is a mid-summer species, all my records run from late May through June to July. Andrena nigroaenea perhaps - thats a big Andrena.

[JRsbugs]

Originally Posted by Matt Smith

Andrena humilis is a mid-summer species, all my records run from late May through June to July. Andrena nigroaenea perhaps - thats a big Andrena.

It can't be A. nigroaenea Matt, I have that and got some pics today. It has black hairs on the tail end but also deeper orange pollen hairs.

I was searching something earlier (I don't recall what!) and came across one I took pics of in 2008 which I thought might be A tibialis. I think it's the same species and it was big!

Andrena tibialis?

To round it off, I also had a Nomada which I narrowed down to a likely Nomada fulvicornis..

Nomada goodeniana or not? [alive not pinned]

I like a good detective story! It can be frustrating though..

As a matter of interest, on the bees of Slovenia site A. humilis is said to fly from April..

wild bee

[JRsbugs]

If this calendar on a Dutch site is anything to go by, the best fit for a female in early April is Andrena praecox.

Calendar - wildebijen.nl

A. tibialis female is listed for the end of April.

There's too many brown bees which look the same.

[Jason Green]

The shape of the pronotum on the bee in question doesn't appear on many Andrena spp.; note the flattened area behind the head and anterior to the tegulae, and the way the thorax then rises again behind it. Now, compare this to any other views you have of Andrenids. Then you'll see. This isn't on humilis, which has a more standard and gently-curved thorasic dorsum. Compare with a side-view of A. clarkella if the hairs aren't obscuring it

I don't like to push the point but it's only this difficult and often unsuccessful if you only take field-photographs of them. There's a lot to learn if you ever start with specimens, but very rewarding. 67 isn't a massive number to learn.

Keep an eye out for dead individuals if you prefer; you can pick up a 20x microscope for around £45 online. Good luck!

[JRsbugs]

Originally Posted by Jason Green

The shape of the pronotum on the bee in question doesn't appear on many Andrena spp.; note the flattened area behind the head and anterior to the tegulae, and the way the thorax then rises again behind it. Now, compare this to any other views you have of Andrenids. Then you'll see. This isn't on humilis, which has a more standard and gently-curved thorasic dorsum. Compare with a side-view of A. clarkella if the hairs aren't obscuring it

Jason, if you had looked at the links I gave you would see the shape you refer to on A. humilis.

BC_ZSM_HYM_00232 Andrena humilis | Flickr - Photo Sharing!

I don't like to push the point but it's only this difficult and often unsuccessful if you only take field-photographs of them. There's a lot to learn if you ever start with specimens, but very rewarding. 67 isn't a massive number to learn.

Keep an eye out for dead individuals if you prefer; you can pick up a 20x microscope for around £45 online. Good luck!

If you don't like to push the point, then don't. I'm a big enough girl to know what I want to do and that's not to collect what I aim to protect. But you already know that Jason! My camera and lens has much higher magnification anyway.

[Jason Green]

Last post in the thread. Compare these two:

http://bugguide.net/images/raw/K0N0L...VRIQTRSQDR.jpg and http://bugguide.net/images/raw/BRFKB...DQ80NRLQWR.jpg

Look behind the head for the transverse ridge near head/pronotum in the first photo. Certainly absent in the second. It is also absent in humilis, as it is in the photo you have posted. That specimen on the ZSM account has it's aged head hung, which is exposing more of the declivity than you normally see in real-life, but it still lacks the ridge.

Try the one on BWARS for a better like-for-like comparison: Andrena humilis, which you'll see is quite different, if not just the pronotal structure as far as obvious features and that goes.

How many Andrena have you come across this year? There seems to be more 'types' around here than last year

[JRsbugs]

Jason, I will hold you to your word so please make that you last post.

The images you linked to are poor examples, angle does make a huge difference but I think you are talking up the spout.

Her head.. who knows, she might have some distinguishing feature such as those nobbly antennae. I wonder how many have those hairs hanging from the bottom of the mandibles.