Holoaden Holoaden Holoaden (common name: highland frogs) is a small genus of craugastorid frogs endemic to southeastern Brazil. "Holoaden" is the type genus of subfamily Holoadeninae that was erected in 2008 and placed in family Strabomantidae, erected at the same time. Before that, it was in Brachycephalidae. However, later research has led the whole Strabomantidae, Holoadeninae included, to become included in Craugastoridae. This arrangement is not followed by all, and the AmphibiaWeb still keeps Holoadeninae, and consequently "Holoaden", in Strabomantidae. "Holoaden" grow to snout–vent length at most. Head is narrower than the body. Differentiated tympanic membrane and tympanic annulus are absent.
Tympanic part of the temporal bone part of the temporal bone. In all extant and extinct primates, including humans, the auditory bulla is formed by the petrosal bone (the petrous part of the temporal bone). This is a diagnostic trait that can be used to distinguish primates, including anthropoids, tarsiers, lemurs, and lorises, from all other mammals. Tympanic part of the temporal bone The tympanic part of the temporal bone is a curved plate of bone lying below the squamous part of the temporal bone, in front of the mastoid process, and surrounding the external part of the ear canal. It originates as a separate bone