Scorpions with two metasomae (tails) are extremely rare, with one estimate I saw as one in every 5,000 specimens. This specimen is approximately 3cm long head to stinger and is being maintained in captivity to study its behavior.

I found this using a black light flashlight with BJ Stacey (@finatic) at the Carrie Nation Trailhead parking lot at Madera Canyon, Arizona.

Read a detailed account of this specimen's discovery and observation updates at the journal post linked below:
http://www.inaturalist.org/journal/jaykeller/7020-rare-arizona-bark-scorpion-with-two-metasomas-tails-and-stingers

A green chiton attached to a half crab. We observed this alien looking commensal beast while undertaking an intertidal survey on the reefs off Hawera. It made us jump when we first turned over the rock.