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Photo#877532
Criorhina? - Eristalis flavipes

Criorhina? - Eristalis flavipes
Northfield, Franklin County, Massachusetts, USA
September 19, 2013

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Criorhina? - Eristalis flavipes Criorhina? - Eristalis flavipes Criorhina? - Eristalis flavipes Criorhina? - Eristalis flavipes

Moved

Moved
Moved from Syrphid Flies.

Looks more like Eristalis to
Looks more like Eristalis to me - Criorhina has a straight R4+5 vein, while this fly's vein is curved. Facial shape also looks wrong, though it's hard to tell while this fly is happily feeding!

 
Interesting
I didn't realize Eristalis could have such a furry abdomen.

 
Eristalis tenax is pretty un-
Eristalis tenax is pretty un-hairy, but a fair number of Eristalis (Eoseristalis) are fairly hairy - for example, E. anthophorina and E. fratercula:

and

Someone else just posted an Eristalis and was also surprised by the hairy abdomen, so you're not alone! It surprised me too when I realized the furry fly I'd caught was indeed Eristalis - so furry.

 
Using these wonderfully clear
Using these wonderfully clear images, I've keyed this out to Eristalis bardus - the arista is hairy at the base (hard to see on most images, but not on these!), eye pile evenly distributed (so not E. tenax, which is obvious otherwise), and the bright orange posterior tarsus and overall bumblebee-like appearance are diagnostic of E. bardus. Nice fly!

Later: of course, E. bardus doesn't seem to be recognized as a species, and may be E. flavipes - going to dig for a bit to see if they've been synonymized.

 
The source I need to look at
The source I need to look at is Telford's 1970 "Eristalis (Diptera: Syrphidae) from America North of Mexico" - I'll go grab a look at my university library tomorrow afternoon while some samples run. Sadly we don't have the 1970s available online! So, for now, I'll live this lovely fly unmoved and we'll see what happens. Thanks for your patience!

 
... I'm an idiot, already had
... I'm an idiot, already had the paper on my laptop! So it gets weirder. The "Key to the Genera of Nearctic Syrphidae" lists E. flavipes, but not E. bardus, as a species, as do the other resources there (such as the Field Guide to the Flower Flies of Ontario).

Telford (1970) lists E. flavipes as a synonym of E. bardus - and states that bardus is "the valid name for the species because of priority." (bardus dates to 1829, flavipes to 1849). The original type specimens were lost.

Here's what I propose - let's move this fly to flavipes for now, and I'll post on the Taxonomy Forum asking for thoughts. Sound good?

 
Sounds good
Strange that several references list both as valid species--ITIS being another example. If Telford (1970) was the last revision of the genus, it seems like we should go with E. bardus, but maybe it makes sense to ask one of the authors of the new key.

 
Say names
Bardus is a Say name (Milesia bardus Say, 1829). Say's insect collection was eaten by beetles, leaving doubt of the identity of his species. Some authors have applied his names to the most similar or most common species matching the description. Others have refused to use his names without a type specimen.

Wirth et al. (in Stone 1965(1)) gave bardus precedence over flavipes Walker. They also noted Musca americana Swederus 1787 as the probable oldest name, but invalid as a junior homonym of a Fabricius name.

 
Ahh - I didn't realize it was
Ahh - I didn't realize it was beetles, just that it was lost! Seems a somewhat reasonable argument for concern over the species identities. I may need to email one of the syrphid academics to ask if they have thoughts on a more modern key or at least species list...

 
Thanks!
According to this page, that is in subgenus Eristalis. Is that correct?

 
Hmm. If it is - as that page
Hmm. If it is - as that page suggests - synonymized with E. flavipes, it should still be in subgenus Eoseristalis - as I understand it, subgenus Eristalis only contains one species in our area, E. tenax, which is introduced.