coracohyomandibularis

The cranial muscles of batoids are basically similar to sharks, although some of the homologies are unclear (e.g., the "X" muscle of electric rays), the muscles are depressed in form (e.g., preorbitalis), some muscles may be lacking (e.g., intermandibularis), and some muscles may be unique to batoids (e.g., coracohyomandibularis) (Miyake et al., 1992),

2004, Jeffrey C. Carrier, John A. Musick, Michael R. Heithaus, editors, Biology of Sharks and Their Relatives, CRC Press, page 183

Batoids also have two unique muscles that depress the hyomandibular cartilage, a depressor hyomandibularis and coracohyomandibularis muscle (Marion, 1905; Miyake et al., 1992; Wilga and Motta, 1998b).

2015, Anthony Peter Farrell, Colin Brauner, Robert E. Shadwick, editors, Physiology of Elasmobranch Fishes: Structure and Interaction with Environment, Elsevier Science, page 159

The sternohyoideus extends from the fascia ventral to the coracohyomandibularis and inserts onto the hypohyal cartilage (Figure 5.5E).

2018, Rui Diogo, Janine M. Ziermann, Julia Molnar, Natalia Siomava, Virginia Abdala, Muscles of Chordates: Development, Homologies, and Evolution, CRC Press, unnumbered page

New muscles also evolved within batoids to move the cranium vertically (levator and depressor rostri), to depress and retract the hyomandibular cartilage (coracohyomandibularis, depressor hyomandibularis), and to depress the lower jaw (depressor mandibularis) (Fig. 8.8) (Miyake 1988; Miyake et al. 1992).

2019, Ian Q. Whishaw, Vincent Bels, editors, Feeding in Vertebrates: Evolution, Morphology, Behavior, Biomechanics, Springer International Publishing, page 249