Niolamia argentina

Paulina-Carabajal, Ariana, Sterli, Juliana, Georgi, Justin, Poropat, Stephen F & Kear, Benjamin P, 2017, Comparative neuroanatomy of extinct horned turtles (Meiolaniidae) and extant terrestrial turtles (Testudinidae), with comments on the palaeobiological implications of selected endocranial features, Zoological Journal of the Linnean Society 180 (4), pp. 930-950 : 936

NIOLAMIA ARGENTINA

The endocranial structures of N. argentina are not clearly visible in the CT scans, preventing the reconstruction of detailed structures such as neurovascular elements, and also the semicircular canals of the inner ear ( Fig. 2 ). The general morphology of the complete cranial endocast, including the nasal cavity, is shown in Figure 5C, F, I .

Figures

Figure 2. Digital reconstruction of the skull of Niolamia argentina (MLP 26–40) in dorsal (A, B), ventral (C, D) and anterolateral (E, F) views. In the images at the left the bone is rendered semitransparent to allow observation of internal structures. Abbreviations: ane, apertura narium externa; ani, aperture narium interna cav, cavum nasi proprium; co, condylus occipitalis; end, cranial endocast; h, skull horn; max, maxilla; nar, nare/narina; orb, orbit; snt, snout; ves, vestibulum. Scale bar = 5 cm.

Figure 5. Cranial endocasts and nasal cavities of the meiolaniid turtles Meiolania platyceps (A, D, G), Gaffneylania auricularis (B, E, H) and Niolamia argentina (C, F, I), in dorsal (A–C), left lateral (D–F) and dorsal (G–I) views. Abbreviations: asc, anterior semicircular canal; ca, cerebral artery; cav, cavum nasi proprium; cer, cerebral hemisphere; de, dorsal expansion; fjp, foramen jugulare posterius; fo, fenestra ovalis; ic, internal carotid artery; ie, inner ear; lag, lagena; lsc, lateral semicircular canal; med, medulla oblongata; met, metotic passage for cranial nerves (CNs) IX–XI; nas, nasal cavity; nphd, nasopharyngeal duct; pit, pituitary; ns, nasomaxillary sinus; psc, posterior semicircular canal; sep, septum; tym, tympanic branch of glossopharyngeal nerve; ves, vestibulum; V, IX–XII, CNs; 1, partial posterior subdivision of the dorsal surface of the cavum nasi proprium of Niolamia argentina. Not to scale.