you could always call him hylidae. a bit less specific

Quibbling a bit here, but the hylidae are actually a very large family of frogs, so you could be referring to even very distant cousins of mine, with some very unsavory habits, some of them, I'm sure. The Hylas are included in a subfamily of the hylidae, known as the hylinae. In doing the a little web research just now to be sure I was using the proper terms for the taxonomic levels, I found the following tidbit: "Among the most bizarre hyline frogs are certain casque-headed genera, such as Triprion and Trachycephalus, in which the skull bones are elaborated into a solid helmet."

See, I'm not menacing, just dense.

Also- Hyla, the taxonomic name, apparently comes from Hylas, a companion of Hercules (some accounts say he was H's squire), who was lured to a limpid pool by a clutch of lovely water nymphs. They were so taken by his handsome visage that they ensorcelled him to stay with them forever. In some accounts of the myth there was just one nymph, but forever's a long time, so I prefer the other version.