''Chlamydoselachus'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

shark Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachi ...

s and the sole extant member of the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Chlamydoselachidae, in the order

Hexanchiformes The Hexanchiformes are the order consisting of the most primitive types of sharks, and numbering just seven extant species. Fossil sharks that were apparently very similar to modern sevengill species are known from Jurassic specimens. Hexanchif ...

. It contains two extant and four extinct species. The most widely known species still surviving is the frilled shark (''Chlamydoselachus anguineus''). It is known as a living fossil, along with ''Chlamydoselachus africana'', also known as the

southern African frilled shark The southern African frilled shark (''Chlamydoselachus africana'') is a species of shark in the family Chlamydoselachidae, described in 2009. It is found in the deep waters off southern Angola to southern Namibia. This species is difficult to d ...

, which is only found along coastal areas of South Africa. The only two extant species of this genus are deep-sea creatures which are typically weakened in areas closer to the surface. While the two extant species are similar in external appearance, they differ internally. The earliest known fossil members of the genus are ''C. gracilis'' from

Angola , national_anthem = " Angola Avante"() , image_map = , map_caption = , capital = Luanda , religion = , religion_year = 2020 , religion_ref = , coordina ...

and ''C. balli'' from

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

, both from the

Campanian The Campanian is the fifth of six ages of the Late Cretaceous Epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campani ...

stage of the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', ...

. Formations with fossil ''Chlamydoselachus'' teeth are thought to be composed of deep-sea sediments, indicating that they have long inhabited deep-sea environments. Fossil ''Chlamydoselachus'' teeth closely resemble those of modern members.

Species

* '' Chlamydoselachus africana'' Ebert & Compagno, 2009 (southern African frilled shark) * '' Chlamydoselachus anguineus''

Garman Garman is a surname or first name. Notable people with the name include: Sports * Ann Garman, All-American Girls Professional Baseball League player * Judi Garman (born 1954), American softball coach * Mike Garman (born 1949), American baseball pla ...

, 1884 (frilled shark) * †'' Chlamydoselachus balli'' Cappetta, Morrison & Adnet, 2019 * †'' Chlamydoselachus garmani'' Welton, 1983 * †'' Chlamydoselachus gracilis'' Antunes & Cappetta, 2002 * †'' Chlamydoselachus lawleyi'' Davis, 1887 * †'' Chlamydoselachus tobleri'' Leriche, 1929

Many other species formerly described in this genus were moved to the fossil genus '' Rolfodon'' in 2019. ''Chlamydoselachus'' and ''Rolfodon'' can be distinguished from one another by their tooth morphologies. ''Rolfodon'' also survived the Cretaceous-Paleogene extinction event but went extinct during the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

References

Chlamydoselachidae Extant Campanian first appearances Shark genera Taxa named by Samuel Garman Campanian genus first appearances {{shark-stub