( Sioux: "little cat man") is an extinct genus of

primate Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians ( monkeys and apes, the latter including ...

belonging to

Adapiformes Adapiformes is a group of early primates. Adapiforms radiated throughout much of the northern continental mass (now Europe, Asia and North America), reaching as far south as northern Africa and tropical Asia. They existed from the Eocene to the M ...

Description and significance

With a weight of approximately five pounds, around a foot tall and resembling a

lemur Lemurs ( ) (from Latin ''lemures'' – ghosts or spirits) are wet-nosed primates of the superfamily Lemuroidea (), divided into 8 families and consisting of 15 genera and around 100 existing species. They are endemic to the island of Madagas ...

, ''Ekgmowechashala'' is the only known North American primate of its time; it lived during the late Oligocene and early

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 ...

Classification

The classification of this form has long been problematic. It was variously classified as a member of the extinct family

Omomyidae Omomyidae is a group of early primates that radiated during the Eocene epoch between about (mya). Fossil omomyids are found in North America, Europe & Asia making it one of two groups of Eocene primates with a geographic distribution spanning h ...

(related to tarsiers) and the equally extinct Plagiomenidae (related to

colugo Colugos () are arboreal gliding mammals that are native to Southeast Asia. Their closest evolutionary relatives are primates. There are just two living species of colugos: the Sunda flying lemur (''Galeopterus variegatus'') and the Philippine fly ...

s), but has been recently reassigned to

, the extinct relatives of

s and other

strepsirrhine Strepsirrhini or Strepsirhini (; ) is a suborder of primates that includes the lemuriform primates, which consist of the lemurs of Madagascar, galagos ("bushbabies") and pottos from Africa, and the lorises from India and southeast Asia. Colle ...

s. A cladistic analysis by Ni et al. (2016) reaffirmed the adapiform placement of ''Ekgmowechashala'' by recovering it as sister group to ''

Bugtilemur ''Bugtilemur'' is an extinct genus of Strepsirhine primate belonging to the adapiform family Ekgmowechashalidae.It is represented by only one species, ''B. mathesoni'', which was found in the Chitarwata Formation of Pakistan. When first describ ...

'', '' Gatanthropus'', and ''

Muangthanhinius ''Muangthanhinius'' is a genus of adapiform primate that lived in Asia during the late Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Per ...

'' in Ekgmowechashalidae.

Paleobiology

The shape of its teeth, and their likeness to those of

raccoon The raccoon ( or , ''Procyon lotor''), sometimes called the common raccoon to distinguish it from other species, is a mammal native to North America. It is the largest of the procyonid family, having a body length of , and a body weight of ...

s, indicate that it ate soft fruit provided by the warm forests of the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico ...

during the early Miocene.

Fossils

Fossil evidence of ''Ekgmowechashala'' was discovered on the

Pine Ridge Indian Reservation The Pine Ridge Indian Reservation ( lkt, Wazí Aháŋhaŋ Oyáŋke), also called Pine Ridge Agency, is an Oglala Lakota Indian reservation located entirely within the U.S. state of South Dakota. Originally included within the territory of the Gr ...

, an

Oglala Sioux The Oglala (pronounced , meaning "to scatter one's own" in Lakota language) are one of the seven subtribes of the Lakota people who, along with the Dakota, make up the Očhéthi Šakówiŋ (Seven Council Fires). A majority of the Oglala live o ...

Native American reservation in

South Dakota South Dakota (; Sioux: , ) is a U.S. state in the North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Lakota and Dakota Sioux Native American tribes, who comprise a large porti ...

. Molars were found in 1981 in the basin of

John Day River The John Day River is a tributary of the Columbia River, approximately long, in northeastern Oregon in the United States. It is known as the Mah-Hah River by the Cayuse people, the original inhabitants of the region. Undammed along its entire ...

, and these are in the collection of the

Burke Museum of Natural History and Culture The Burke Museum of Natural History and Culture (Burke Museum) is a natural history museum in Seattle, Washington, in the United States. Established in 1899 as the Washington State Museum, it traces its origins to a high school naturalist club fo ...

; in the summer of 1997 John Zancanella of the Bureau of Land Management found a lower molar in the

John Day Fossil Beds National Monument John Day Fossil Beds National Monument is a U.S. national monument in Wheeler and Grant counties in east-central Oregon. Located within the John Day River basin and managed by the National Park Service, the park is known for its well-preserved l ...

. ''Ekgmowechashala philotau'', known from material in Nebraska and South Dakota, was thought to be the only species of this genus, but material from Oregon has been recently described as a new species, ''E. zancanellai''. A tooth from the Toledo Bend Ranch Local Fauna of far eastern

Texas Texas (, ; Spanish: ''Texas'', ''Tejas'') is a state in the South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by ...

has been assigned to this genus.

References

{{Taxonbar, from=Q5350406, from2=Q24175560 Prehistoric primate genera Miocene primates Oligocene primates Miocene mammals of North America Oligocene mammals of North America Prehistoric mammals of North America Primates of North America Paleogene geology of Oregon Paleogene geology of South Dakota John Day Fossil Beds National Monument Oligocene genus first appearances Miocene genus extinctions Fossil taxa described in 1963