Ascaphus truei Coastal Tailed Frog
Some other names for this species:
Pacific Tailed Frog, Western Tailed Frog, Tailed Frog
Prairie Creek Redwoods State Park, Humboldt County, CaliforniaMarch 25, 2006
Coastal Tailed Frog (Ascaphus truei) Coastal Tailed Frog (Ascaphus truei)
Tailed Frogs are considered to be (along with a handful of New Zealand frogs) the most primitive living frogs. The word "primitive" is somewhat misleading. It doesn't mean that these frogs are somehow "less evolved" than other frogs, since all living frogs have been evolving for the same span of time. What this really means is that all other types of living frogs are more closely related to each other than they are to Tailed Frogs and their New Zealand relatives.

Tailed Frogs don't actually have tails; the males have a copulatory organ approximately where a tail would be. The only one I've come across so far was a female, so there's no sign of a "tail" here.

Until recently, all tailed frogs were classified in this species, which was the only species in its genus, which is the only genus in its family. A few years ago the population of tailed frogs in the Rocky Mountains was reclassified as a separate species, the aptly-named Rocky Mountain Tailed Frog (Ascaphus montanus).

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