Othniel Charles Marsh first named it as a species of Pterodactylus: P. montanus, the specific name meaning "from the mountains" in Latin, but soon changed his mind and gave it a new generic name. At the same time he assigned another wing bone, teeth, vertebrae, and a scapulacoracoid to it, but this material is probably too large to belong to the type individual.
Othniel Charles Marsh initially labeled it as Pterodactylus montanus, with "montanus" denoting "from the mountains," but subsequently reclassified it under a new genus. Concurrently, he also assigned other wing bones, teeth, vertebrae, and a scapulacoroid to it; nonetheless, this material is probably too substantial to be part of the original specimen.