My neighbor works at the Freshwater Institute and I took my parasite to her and someone there identified it for me. This is the email I got from him:
How the heck it arrived in my tank is anyone's guess!
Hi Karen,
Christine lent me your leech for identification, and after a good look I’d say that this is a Placobdella ornata. This species of leech is common and has a wide distribution throughout North America. There’s a large variety of shapes and sizes, and they can be either free-living or parasitic to fish and other aquatic species (in fact the common name for this species is the “turtle leech”). Unless there’s an infestation of these leeches in your aquarium then I wouldn’t be overly concerned about the health of your fish being detrimentally affected.
Hope this helps!
How the heck it arrived in my tank is anyone's guess!