The answer to your question is both easy and difficult.I heard that they are the same the P cancirades and P.atrichromatus. Does anyone have a pics to compare and contrast this two sp. if there are really two different sp ?
Unless you actually key it out and KNOW that it is P. cancerides, assume it to be different. Actually, I've got both varieties and they look different. I haven't keyed out either yet, so I don't know the "purple" species and "cancerides" hasn't been proven.So would the Phormictopus sp. purple just be a regular p cancerides. I see an mm for sale and I want to know if I could breed it with my p cancerides.