Subject: Hellgrammite pupa
Location: Black River, Springfield VT
June 22, 2012 7:48 am
Our daughter found this under a rock as she was fishing down at our local river. We love river-bugs (benthic macroinvertebrates), as I am the director of the Black River Action Team, a grassroots river group in Windsor County, in SE Vermont.
We have this pupa in a terrarium; it’s been curled up and dormant (unless disturbed, then it wriggles around energetically!) since June 14th. So far, it’s been 8 days…I’m interested to learn how long the pupal stage lasts! I understand the females live as adults just long enough to mate and then lay eggs on structures or vegetation that overhang the water — like the bridge abutments where our daughter was fishing.
Signature: Kelly Stettner, BlackRiverActionTeam.com
We have just started getting Dobsonfly identification requests, and they generally continue until July, so we expect your Hellgrammite Pupa should metamorphose into an adult soon. Since warmer temperatures arrive later in Vermont than in the more southern portion of the range of the Dobsonfly, you might have a slightly longer wait. We are uncertain how long the pupal stage of the Dobsonfly lasts, but we know it is not more than a single season. We expect that pupation takes place in spring to account for a summer emergence.
Daniel, this is great; thank you so much! I am learning more about bugs than ever before in my life, since moving to our home on the river bank in 2010. Lots of ID information comes from helping our state water quality lab do “bug picking” each January, but a lot comes from searching the internet and scouring your site. Learning how the macro setting on my digital camera works has been a big help — got some awesome close-up shots of a burrowing mayfly larvae a couple of years ago!
Would you folks prefer more questions about identification, or are specific queries okay, like my question about the pupal stage of the hellgrammite?
Hi again Kelly,
We would really like images of underrepresented species for our site. We don’t have as many aquatic insects as we would prefer. Please put the insect name in the subject line to grab our attention. That said, all inquiries are welcomed, but we can only answer and post a few a day.