Acutalamna karsteni
Guinot & Carrillo-Briceño, 2018
Classification: Elasmobranchii Lamniformes incet. sedis
Reference of the original description
Lamniform sharks from the Cenomanian (Upper Cretaceous) of Venezuela. Cretaceous Research, 82, 1–20
Lamniform sharks from the Cenomanian (Upper Cretaceous) of Venezuela. Cretaceous Research, 82, 1–20
Description:
Citation: Acutalamna karsteni Guinot & Carrillo-Briceño, 2018: In: Database of fossil elasmobranch teeth www.shark-references.com, World Wide Web electronic publication, Version 08/2026
Description
Original diagnosis after Guinot & Carrillo-Briceño, 2018 [25801]: Lamniform with gradient monognathic heterodonty. Cuspidate teeth higher than wide. Slender main cusp weakly (anterior teeth) to strongly (laterals) bent distally, devoid of lateral cusplets; main cup sigmoid in labial and profile views. Lateral heels oblique in anterior teeth; mesial heel incipient to absent in more lateral tooth files. Cutting edges smooth, low and thin. Large crown neck. U-shaped root of anaulacorhize stage. Root bilobate, asymmetrical with more developed and thinner mesial lobe; strong and protruding lingual protuberance with central foramen. Labial root face with variable number of foramina below the crown/root edge. More lateral teeth strongly asymmetrical with short and stubby mesial root lobe and incipient or no mesial crown heel; basal root edge curved and wide. Heels absent in latero-posterior teeth.
Original diagnosis after Guinot & Carrillo-Briceño, 2018 [25801]: Lamniform with gradient monognathic heterodonty. Cuspidate teeth higher than wide. Slender main cusp weakly (anterior teeth) to strongly (laterals) bent distally, devoid of lateral cusplets; main cup sigmoid in labial and profile views. Lateral heels oblique in anterior teeth; mesial heel incipient to absent in more lateral tooth files. Cutting edges smooth, low and thin. Large crown neck. U-shaped root of anaulacorhize stage. Root bilobate, asymmetrical with more developed and thinner mesial lobe; strong and protruding lingual protuberance with central foramen. Labial root face with variable number of foramina below the crown/root edge. More lateral teeth strongly asymmetrical with short and stubby mesial root lobe and incipient or no mesial crown heel; basal root edge curved and wide. Heels absent in latero-posterior teeth.
Remarks
shark-references Species-ID=14955;
type species of Acutalamna Guinot & Carrillo-Briceño, 2018 [25801] by original designation (Art. 68.2 ICZN);
shark-references Species-ID=14955;
type species of Acutalamna Guinot & Carrillo-Briceño, 2018 [25801] by original designation (Art. 68.2 ICZN);
References
Lamniform sharks from the Cenomanian (Upper Cretaceous) of Venezuela. Cretaceous Research, 82, 1–20
DOI: 10.1016/j.cretres.2017.09.021
Lamniform sharks from the Cenomanian (Upper Cretaceous) of Venezuela. Cretaceous Research, 82, 1–20
DOI: 10.1016/j.cretres.2017.09.021
