Myogale mylohyoideus

WHIDDEN, HOWARD P., 2000, Comparative Myology of Moles and the Phylogeny of the Talpidae (Mammalia, Lipotyphla), American Museum Novitates 3294, pp. 1-53 : 9

M. mylohyoideus , pars profundus

ORIGIN: From the medial surface of the mandible. The anterior fibers extend transversely, whereas the more posterior fibers extend posteromedially.

INSERTION: In a midventral raphe with fibers of the antimere, with the posteriormost fibers attaching to the basihyal cartilage.

REMARKS: This muscle has the same general form in the 11 study taxa. The midventral raphe of this muscle is firmly attached to M. geniohyoideus .

FACIAL FIELD

The muscles supplied by the facial nerve are typically split into two groups, the superficial facial muscles, or muscles of expression, and the hyoid constrictor muscles. The superficial facial muscles of therian mammals consist of three distinct layers: M. sphincter colli superficialis, M. platysma , and M. sphincter colli profundus (Huber, 1930, 1931). M. sphincter colli superficialis is the most superficial of these and has transverse fibers, M. platysma is the middle layer and has longitudinal fibers, and M. sphincter colli profundus is the deepest layer and has transverse fibers. According to Huber, M. sphincter colli superficialis forms at most a simple band encircling the neck, whereas Mm. platysma and sphincter colli profundus give rise to a diversity of specialized facial muscles. I interpret the facial muscles of talpids in this way, and follow Huber’s classification in my treatment of these muscles. Meinertz (1978a & 1978b) described in detail the facial muscles of Erinaceus , Talpa , Suncus (his Pachyura ), and Sorex . Although I disagree with some of his interpretations, I have followed his names for these muscles except where noted. Uropsilus has a well­developed ear pinna, with a number of associated muscles not found in other talpids; these muscles are not described here.

Superficial Facial Group