Altusmirus triquetrus

FUCHS, ENGELBRECHT, LUKENEDER & KRIWET, 2017


Classification: Elasmobranchii Carcharhiniformes incert. fam.

Reference of the original description
FUCHS, I. & ENGELBRECHT, A. & LUKENEDER, A. & KRIWET, J. (2018)
New Early Cretaceous sharks (Chondrichthyes, Elasmobranchii) from deep-water deposits of Austria. Cretaceous Research, 84: 245-257

Types
Altusmirus triquetrus
Holotype: NHMW: 2017/0053/0001; Paratype: NHMW: 2017/0053/0002-0013;

Images of types

Description:


Citation: Altusmirus triquetrus FUCHS, ENGELBRECHT, LUKENEDER & KRIWET, 2017: In: Database of fossil elasmobranch teeth www.shark-references.com, World Wide Web electronic publication, Version 01/2021

Please send your images of "Altusmirus triquetrus" to info@shark-references.com

Altusmirus triquetrus anterior tooth (NHMW, 2017/0053/0001) © Iris Feichtinger, Vienna

Description
Original diagnose after Fuchs et al. (2017) p. 247-248 [25903]: Small carcharhinid shark characterized by a heterodont dentition with small teeth having a root that is higher than the crown. The main cusp is triangular and the cutting edges are continuous between the blunt apex and the lateral cusplets. The main cusp is flanked by one pair of well-defined, divergent lateral cusplets and an additional pair of incipient accessory cusplets. Lateral cusplets are more erect than the main cusp and in front of the plane of the main cusp in mesial and distal views. All cusps have a transversally convex lingual face that is completely devoid of any ornamentation. The labial crown face is rather flat and, conversely, possesses elongated, vertical enameloid ridges. The crown-root neck is markedly incised. The root is massive, “secondary anaulacorhize” (according to Cappetta, 2012), and trunk-like. It distinctly flares basally and is in occlusal view triangular, jutting out below the cusp on all sides. The basal root face is broad and flat. Lingually, a central foramen below the main cusp is only observable at the holotype, all other teeth lack this character. Additionally, one pair of margino-lingual foramina is developed. Labially, one prominent and displaced oval foramen also is discernible.

Remarks
type species of Altusmirus Fuchs et al., 2017 p. 247 [25903] by original designation (Art. 68.2 ICZN);

valid after Fuchs et al. (2017) p. 247 [25903];


References
FUCHS, I. & ENGELBRECHT, A. & LUKENEDER, A. & KRIWET, J. (2018)
New Early Cretaceous sharks (Chondrichthyes, Elasmobranchii) from deep-water deposits of Austria. Cretaceous Research, 84: 245-257
DOI: 10.1016/j.cretres.2017.11.013