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Photo#192943
Water beetle larva? - Acilius

Water beetle larva? - Acilius
Windham, Rockingham County, New Hampshire, USA
June 19, 2008
Size: about 26 mm
I found this larva in the soggy, rotting leaves at the water's edge at a small, shallow pond in mixed woods. Somehow it reminded me of some of Tom Murray's Water Beetle larvae. If that's what this one is, it is my first one. This larva twitches and thrashes violently and seems to mainly lie on its side in the rearing container. I wonder if it is ready to pupate.

Oh yeah, the others in the shot are a scaphidiine rove (right) and an Oxyporine rove (left).

Images of this individual: tag all
Water beetle larva? - Acilius Water beetle larva? - Acilius Water beetle larva? - Acilius Water beetle larva? - Acilius Water beetle larva? - Acilius Water beetle larva? - Acilius Water beetle larva? - Acilius

Moved
Moved from Acilius.

Moved

Acilius sp.
confirmed via larva key from Larson (2001)...note the deeply bifid (2-pronged) ligula (structures located between labial palps), which is barely visible in the headshot

Next time if you do collect and photograph any dytiscid larva, include close-up ventral and dorsal shots of the head and body and also the cerci and last 2 abdominal segments.

 
I should have slowed this guy down
with a dose of ethyl acetate so I could get better detail shots. Thanks for the help, Tim.

It is similar to Acilius, alt
It is similar to Acilius, although I am not sure

Alas!
I didn't segregate the larva soon enough. Other beetles made a feast of it, leaving only the chitinous parts.

 
Too bad...
I had a feeling it was something like Aci*lius, but I don't know the larvae, of course. I've discovered how easy it is to obtain these larvae by sifting pond-edge detritus and vegetation with a kitchen strainer. Definitely very effective for finding cryptic odonate naiads.

 
I may return to that pond

 
Looks awesome.
Happy hunting! :-)

Certainly
It's a dytiscid larva, probably getting ready to pupate since you found it close to water but not in it. I've seen very similar ones hanging by their tail ends from the water surface, in a fashion similar to the adults.

 
Thank you, Stephen.
If it matures, we'll get a closer ID maybe.

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