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possible hellgrammite?  please help to identify.

possible hellgrammite? please help to identify.
Marietta, Lancaster County, Pennsylvania, USA
May 19, 2009
Size: 3.5 inches
This critter was found under a log within 20ft of the Susquehanna River. Thinking maybe the Hellgrammite, but we're not sure. Any info regarding this cutie would be appreciated.

Fishfly larva

This is the larva of a Fishfly, as your photos reveal breathing tubes extending from the end of its abdomen.   Only the larva of a Dobsonfly is properly referred to as a Hellgrammite. Fishflies are closely related to Dobsonflies.   Both belong to order Megaloptera, family Corydalidae.   However, Dobsonflies are in subfamily Corydalinae, and Fishflies are in subfamily Chauliodinae.   This can visualized somewhat easier at Alderfly, Dobsonfly, Fishfly Taxonomic Structure.

thank you
It's interesting that the website TroutNut (?) is having a bit of a debate about this very subject. Most people commonly use "hellgrammite" for both, the fishfly and the dobsonfly larva. I wondered what the difference was between the two, besides subfamily. Thank you very much for letting me know. Now, we'll be on a quest to find the REAL hellgrammite. lol


Hi Heather,

Some observable differences between dobsonfly and fishfly larvae are size (mature dobsonfly larvae are much larger), breathing tubes (only fishfly larvae have them), and gill tufts adjacent to lateral filaments (only dobsonfly larvae have them).

What (at first glance) appeared (to my tired eyes) to be breathing tubes on your specimen, as I now look at it more closely, are really just lateral filaments on the last abdominal segment, and not breathing tubes, which would be attached somewhat anterior of the last abdominal segment, and would be larger, longer, and shaped like a ridged flexible hose. So, your specimen is actually a dobsonfly larva, and your quest to find a REAL Hellgrammite should be considered complete. Incidentally, the last post on that old TroutNut thread was mine.

Maybe a dobsonfly larva (hellgrammite)...
... but it could also be a fishfly larva, for example: . You can find more info on both here

Family Corydalidae.

By the way....
What does this dear turn into? What changes take place, if any?
Aileen (my 7 year old daughter) :)

Don't scare Aileen -
they don't bite people - but here is a male Dobsonfly:
Isn't he impressive? And big, too: 3 to 4 inches.

this cutie
thanks so much!! i think we may take him back to the log we found him under. may consider leaving him under the bark in the tank to see if he changes. he seems content at this point. not sure what to do. my little Aileen isn't afraid of much, when it comes to insects. we both love them!! :)