Vocal Sacs


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Related to Vocal Sacs: Vocal Pouch

Vocal Sacs

 

hollow projections of the walls of the mouth cavity in males of ecaudate amphibians. The vocal sacs are filled with air and exhaled; they function as resonators of the vocal apparatus to increase voice power. Most frogs have paired vocal sacs extending from the angles of the mouth; tree toads and other toads have a single projection on the bottom of the mouth cavity.

References in periodicals archive ?
Da Silva (1998) did not include vocal sac architecture as one of his characters but this character must represent some sort of homoplasy, given his cladogram.
The next day seven males called from water; these males moved around the pond with all legs extended and the black lateral vocal sacs inflated.
Cei (1980) reported that vocal sacs resemble white balloons on either side of the head.
For the diagnoses, the following numbered elements do not exhibit variation: (1) skin of venter areolate or granular; no dorsolateral folds; (4) upper eyelid broader than IOD, no cranial crests; (6) males with large subgular vocal sac, no nuptial pads; (7) first finger shorter than second; (9) no ulnar tubercles; (10) no tubercles or folds on heel or tarsus; (11) no supernumerary plantar tubercles; (12) fifth toe much longer than third.
Stanley Rand concluded in 1993, so they dismissed the idea of vocal sacs as resonating cavities.
Dorsum, chest, and gula smooth; belly skin granular; vocal sac prominent tending to be bilobed when inflated; an incomplete chest fold, folds of skin at wrist, knee and heel; axillary membrane small.
To beat their competitors in the fight for females, these tiny frogs have a built-in volume control: an inflatable vocal sac (balloonlike pouch) beneath the mouth.