Florida's Meske's skipper was gone for a decade before returning.Photo: Mary Keimat/Flickr
A story from Florida makes it clear how unclear the status of a species can be when it comes to government listings.
If a species was never listed as threatened or endangered, but it appears to be extirpated or even extinct, it falls into a odd gray area. The government won’t declare them extinct. Technically, if we keep a species off the endangered species list, then it can’t go extinct.
The rockland Meske’s skipper appeared to be gone for good but the state government didn't want to declare them extinct. Then, it was seen again.
The species in Florida include two that have endangered status and two (the Florida leafwing and Bartram’s scrub-hairstreak) have been elevated to “candidates.” The agency won’t add something just to turn around and stamp it extinct.
Source: Mother Jones "5 Butterfly Species Just Vanished While No One Was Looking"