- Source: Rolfodon
Rolfodon is an extinct genus of shark in the family Chlamydoselachidae. It is closely related to the extant frilled sharks in the genus Chlamydoselachus, which it can be differentiated from by tooth morphology. It is named after late Canadian paleontologist Rolf Ludvigsen.
The earliest fossil teeth of Rolfodon are known from the Late Cretaceous (Campanian), and it is one of two genera of Chlamydoselachidae along with Chlamydoselachus known to have survived the Cretaceous–Paleogene extinction event, although unlike Chlamydoselachus, Rolfodon went extinct by the Late Miocene. Remains are known from worldwide, including Canada, Austria, New Zealand, Angola, Ecuador, and Antarctica. As with modern frilled sharks, Rolfodon appears to have been specialized to deep-water environments.
Species
The following species are known:
R. bracheri (Pfeil, 1983) – Early Miocene of Austria
R. fiedleri (Pfeil, 1983) – Eocene of Austria
R. goliath (Antunes & Cappetta, 2002) – Late Cretaceous of Angola
R. keyesi (Mannering & Hiller 2008) – Early Paleocene of New Zealand
R. landinii (Carrillo-Briceño et al. 2014) – Late Miocene of Ecuador
R. ludvigseni Cappetta, Morrison & Adnet, 2019 – Late Cretaceous of Canada
R. tatere (Consoli, 2008) – Late Cretaceous to Early Paleocene of New Zealand and Antarctica
R. thomsoni (Richter & Ward, 1990) – Late Cretaceous of Antarctica
The majority of these species were previously classified in Chlamydoselachus. One species, Chlamydoselachus baumgartneri, was moved to its own genus Proteothrinax in 2012. P. baumgartneri was later found to be conspecific with the previously described C. fiedleri, but fiedleri was found to belong to Rolfodon by Cappeta et al (2019).
R. goliath, from the Late Campanian of Angola's southern Benguela Basin, could grow to very large sizes. It was described by Miguel Telles Antunes and Henri Cappetta in 2002 during the beginning stages of the PaleoAngola project. The holotype, MUS ANG 23, is rather large. This tooth is about 20mm high, and is characterised by straightened, upright cusps with smooth enameloid which lack ornamentation.
In addition to the genus as a whole, one individual species is also known to have survived the Cretaceous-Paleogene extinction event: R. tatere, which was first described from the Early Paleocene of New Zealand and was later also identified from the Late Cretaceous of Antarctica, extending the record of its existence by over 10 million years.
References
Kata Kunci Pencarian:
- Chlamydoselachidae
- Rolfodon
- Chlamydoselachidae
- Hexanchiformes
- Chlamydoselachus
- Dykeius
- List of vertebrate fauna of the Campanian stage
- 2014 in paleoichthyology
- Northumberland Formation
- List of prehistoric cartilaginous fish genera
- 2019 in paleoichthyology