Doug Smith has been the expert on spineless creatures that inhabit the freshwaters of New England.  He taught invertebrate biology at UMass Amherst and managed the Invertebrate Collection at that school. His power was not just his academic interest in such animals, it was his field work. He toured the state many times, visiting all waters and making collections.  He published a guide to the Freshwater Macroinvertebrates of Massachusetts.  It not only allows you to identify this poorly studied group, it gives you the locations of where he found them.

This leads me

to the crayfish of the Ipswich River.  According to Doug, the only crayfish likely to be found in our river is “Onconectes virilis”.  The nose or rostrum looks like Doug’s figure 7.13. For crayfish identification, a good place to start is to look at this rostrum.  The blunt one in Fig 7.11 is a different genus, Cambarus and 12& 13 are Onconectes.

If it turns out to be Onconectes, next look at the side of the crayfish. If its spiky like 7.19, please call me. 

If its like Fig 7.21 next check the claws’ thumb.  Notched (7.27) requires you call me and report it.  If its unnotched, it is our common O. virilis.

Doug has generously allowed IRWA to use his identification guide as we see fit.  I hope to use the guide to help us learn what we have and what we can add to Doug’s life work.  These illustrations are his and we use them with his permission.