Kourisodon puntledgensis life reconstruction

''Kourisodon'' ("razor tooth") is an extinct genus of

mosasaur Mosasaurs (from Latin ''Mosa'' meaning the 'Meuse', and Greek ' meaning 'lizard') comprise a group of extinct, large marine reptiles from the Late Cretaceous. Their first fossil remains were discovered in a limestone quarry at Maastricht on th ...

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

s have been found from

Vancouver Island Vancouver Island is an island in the northeastern Pacific Ocean and part of the Canadian Provinces and territories of Canada, province of British Columbia. The island is in length, in width at its widest point, and in total area, while are o ...

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

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 ...

,Nicholls, E. L. and Meckert, D. (2002). Marine reptiles from the Nanaimo Group (Upper Cretaceous) of Vancouver Island. ''Canadian Journal of Earth Science'' 39(11):1591-1603. as well as from the Izumi Group of

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

. These finds date back to the late

Santonian The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series. It spans the time between 86.3 ± 0.7 mya (million years ago) and 83.6 ± 0.7 mya. The ...

stage and the late Campanian to the late Maastrichtian, respectively, 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'', the ...

. ''Kourisodon'' was originally described as a member of the "Leiodontini", more recently as a "Clidastine".

Distribution

''Kourisodon puntledgensis'' is known from a single locality located in the

Pender Formation along the banks of the

Puntledge River The Puntledge River is a small river on Vancouver Island, British Columbia, Canada. It joins the Tsolum River to form the Courtenay River, which enters the Strait of Georgia at the city of Courtenay. Name origin The name is derived from that ...

(after which it was named). ''K. puntledgensis'' was a small mosasaur, with an estimated length of about 3.75 meters (around 12.3 feet). It shared its environment with a variety of

Elasmosaurids Elasmosauridae is an extinct family of plesiosaurs, often called elasmosaurs. They had the longest necks of the plesiosaurs and existed from the Hauterivian to the Maastrichtian stages of the Cretaceous, and represented one of the two groups of p ...

, turtles, and other mosasaurs, although it seems that no

polycotylids Polycotylidae is a family of plesiosaurs from the Cretaceous, a sister group to Leptocleididae. Polycotylids first appeared during the Albian stage of the Early Cretaceous, before becoming abundant and widespread during the early Late Cretaceous ...

were present in its Pacific environment. In 2005, a fragmentary skeleton from exposures of the Izumi Group on Shikoku Island,

, was assigned to ''Kourisodon'' sp. This specimen demonstrated longer maxillary teeth among other differences from ''K. puntledgensis'', which the authors interpreted to mean that this individual belonged to a second species, although this new species has not yet been formally named. Other fragmentary remains from the Izumi Group have been tentatively assigned to ''K.'' sp., some of which represent juvenile animals. A 12' 3" complete replica of the

specimen is on display at the

Canadian Fossil Discovery Centre The Canadian Fossil Discovery Centre, formerly known as the Morden and District Museum, is located in Morden, Manitoba in the lower level of the Access Events Centre. The museum currently houses the largest collection of marine reptile fossils ...

in Morden, Manitoba.

References

External links

''Kourisodon''
in the

Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms. History The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Pale ...

Mosasaurids Mosasaurs of North America Fossil taxa described in 2002 Taxa named by Elizabeth Nicholls {{paleo-lizard-stub