Llanocetus denticrenatus

Llanocetus was an early member of the baleen whale group (Mysticeti) but had teeth instead of baleen. It is known from a fragmentary mandible found on Seymour Island during an Argentine-American expedition in 1974-1975. It lived alongside advanced members of the archaeoceti whales (Dorudontidae) as well as primitive penguins during the Late Eocene period. With an estimated skull length of 2 m, it was a pretty large whale. A more complete fossil has also been excavated but its description has apparently not been published yet.

Name

Llanocetus denticrenatus

Authority

Mitchell, 1989

Meaning of generic name

in honor of Dr. George A. Llano and cetus (L.) whale

Meaning of specific name

"crenated teeth"

Size

Skull length: 2 m, Length: [not given]

Remains

Holotype (USNM 183022): a fragmentary mandible with two cheek teeth.

Referred specimens: a complete skull endocast and other bone fragments.

Age and Distribution

Horizon: Upper part (Unit III) of the La Meseta Formation. Late Eocene (Priabonian).

Locality: Seymour Island, Antarctica.

Classification

Mammalia Cetacea Mysticeti Llanocetidae

Further Reading

E. D. Mitchell. 1989. A new cetacean from the late Eocene La Meseta Formation, Seymour Island, Antarctic Peninsula. Canadian Journal of Fisheries and Aquatic Sciences 46(12):2219-2235.