Fig. 3

Head anatomy of MGGC 1976 (G. cuvieri) with exceptional preservation of soft tissues. Photograph of the head region of the main slab under UV light (a) and interpretive drawing of anatomical structures (b) in dorsal view, compared to the chondrocranium of the living G. galeus (c) in dorsal view. The chondrocranium (c) is modified from [25] and scaled to the same anteroposterior length. The slab was assembled from multiple parts using mortar glue (m1) and reconstructed using pigmented mortar (m2). d Photograph of the head region of the main slab under natural light. e Details of the endocranial cavity and the braincase under UV light. f, g The head region of the counter slab under natural light (f) and outline (g). Abbreviations: 1c, first cervical vertebra; ad, adductor mandibulae; c, cerebellum; cb, ceratobranchial; ce, ceratohyal; cu, cucullaris; e, eye; eb, epibranchials; ep, epaxial muscle; es, endolymphatic sac; h, hyomandibular overlapped by second dorsal constrictors; ie, inner ear; l, lens; la, sensory area with the ampullae of Lorenzini; m1, mortar used to glue parts of the slab; m2, pigmented mortar used to reconstruct anatomical parts; mc, Meckel’s cartilage; mo, medulla oblongata; nc, nasal cavity; ol, optic lobes; op, olfactory peduncle; ot, otic capsule; pb, pharingobranchial; pq, palatoquadrate; prp, preorbital process; r, rostrum; s, patches of dermal denticles; sp, spiracle