Thread subject: Diptera.info :: Empidoidea from California

Posted by John Carr on 25-09-2013 20:01
#1

These were posted originally to BugGuide and are submitted here with the photographer's permission. They are common on small flowers in the redwood forest of coastal California (USA) early in the year.

I have ruled out everything I know.

At first I thought Oedaleinae (e.g. Anthalia) but the Hybos-like projecting proboscis rules out Ocydromiinae and Oedaleinae. The discal cell emits three veins (see third photo), inconsistent with Hybotinae. Iteaphila and Brachystoma would have R4+5 forked. Empidinae would have a downward projecting proboscis. Clinocerinae has the wrong habitat, forked R4+5, and a weak anal lobe. Hemerodromiinae has modified fore legs. Tachydromiinae lack a discal cell. Anthepiscopus seems to differ in detail, but is at least close. Oreogeton lacks the projecting proboscis.

It is possible that two or more species are represented. The antennae vary.

Four from February 12, 2011:

bugguide.net/images/raw/MQFRIQYRXQFR0Q3RIQTR90DRSQJRP0JRXQARZQURM0YQJK9RZQ9RG0TQFKFQ40JQ50K050NRKQZ0N0.jpg

bugguide.net/images/raw/4QV04QB08QV0EQA0LKB09QLSUQ30GKCK9QZSWQ30WQBK9QB0UQLSUQZS9QCK5KDKIKDKMKRSUQY0AQ.jpg

bugguide.net/images/raw/MLVZ4LBZ8LVZML8Z0L6Z4LLR8L9ZEHLR5HOH8HCH9H3H9H3H4LLR2H3H5L3HWHYHML1ZILFHUH9ZPH.jpg

bugguide.net/images/cache/RL4ZQL5Z8L1H9HCH8HOH4HCH7H5ZSLPZ8LUZRLDHMHTHSLBHXHTHIHCHSLBHHLEZKL1HMHBHMH5Z0LBZWHWZIL1Z7L.jpg
(Click for larger size.)

Two from March 20, 2010:

bugguide.net/images/raw/7HFH2HAHIHTHIHEZIHJH6HYHGL2Z0LVH8HOHGH4ZQLVH7HTHZL6ZGLUZ7LBZ5LJHMH1HXHTH8HDHQL.jpg
bugguide.net/images/raw/3LBLSZ6LYLNLYLULIRKHMZDL0ZBLSZAL0ZZHPRQHMRKHXZHHSRYZ0RDZIR9LKRELKRJZIR6LKRDZHZ.jpg

Later in the year small flowers have similar flies with angled proboscis, probably a different species in Oedaleinae.

bugguide.net/images/cache/OLMZBLXZ2L2RTZXRTZXRJZIROZQRFZJLWLYLNL3L2L0Z2L3LFZHZDZ0RJZRZULXRDZ3L9L3L2LLZ9LRZCZIR9LSR9L.jpg

Posted by Paul Beuk on 26-09-2013 16:05
#2

Anthalia comes to mind, but the antennal style is rather long. Unfortunately, wing venation is poorly visible in these pictures.

Posted by John Carr on 26-09-2013 17:54
#3

The last looks like Anthalia, but the rest have a proboscis pointing straight ahead. According to Sinclair and Cumming (2006), Oedaleinae have "mountparts directed obliquely forwards."

Posted by Paul Beuk on 26-09-2013 18:28
#4

Hmm, perhaps then Mythicomyiidae? If I only had an actual specimen. ;)

Posted by John Carr on 26-09-2013 22:01
#5

They can't be Mythicomyia because R2 and CuA are long. If you want to take a trip to California the photographer can set you up with a collecting permit.