FIGURE 6 in Redescription of the Rio skate Rioraja agassizii (Rajiformes: Arhynchobatidae) with notes on internal anatomy and intraspecific variation

FIGURE 6 | Neurocranium of Rioraja agassizii, MNRJ 50512, female, 505 mm TL. A. dorsal, B. ventral, C. lateral views. II, foramen for the optic nerve; III, foramen for the oculomotor nerve; IV, foramen for the trochlear nerve; VI, foramen for the abducens nerve; acvf, anterior canal vein foramen; af, anterior fontanelle; antf, antorbital facet; apba, foramen for the afferent pseudobranchial artery bp, basal plate; epb, epiphysial bridge; end, endolymphatic foramen; ethn, foramen for the passage of the ethmoidal nerve; fm, foramen magnum; hf, hyomandibular facet; hVII, foramen for the passage of the hyomandibular ramus of the facialis nerve; icf, internal carotid artery foramen; inc, inner nasal cartilage; ins, internasal space; ja, jugal arch; na, nasal aperture; nc, nasal capsule; oc, otic capsule; occ, occipital condyle; onc, outer nasal cartilage; opc, opistotic crest; opd, optic pedicel; opf, ophthalmic foramen; ornc oronasal canal; peri, perilymphatic foramen; pf, posterior fontanelle; pfc, prefacial commissure; pnc, posterior nasal cartilage; pos, postorbital process; pre, preorbital process; prf, parietal fossa; prof, prootic formamen; ptp, pterotic process; ra, rostral appendix; rb, rostral base; rn, rostral node; rs, rostrum; soc, supraorbital crest; sopf, superficial ophtalmic foramen.