Calippus placidus Leidy 1869

Mammalia - Perissodactyla - Equidae

Alternative combinations: Calippus (Calippus) placidus, Merychippus placidus, Protohippus (Calippus) placidus, Protohippus placidus

Synonyms: Calippus optimus Quinn 1955, Pseudhipparion optimum Quinn 1955

Belongs to Calippus according to S. R. May 2019

See also Cope 1893, Dalquest and Hughes 1966, Forsten 1975, Gidley 1907, Hay 1902, Hulbert 1988, Johnston 1937, Macdonald 1992, MacFadden 1998, Matthew and Stirton 1930, Osborn 1918, Prado and Alberdi 1996, Quinn 1955, Stirton 1935, Stirton 1940, Voorhies 1990, Webb 1969 and Webb and Hulbert 1986

Sister taxa: none

Type specimens:

  • Calippus placidus: USNM 621, a tooth (A left upper premolar, P2)
  • Calippus optimus: BEG 30896-528, a partial skull (cial portion of skull and lower jaws).


• Miocene of United States (23: Nebraska, South Dakota, Texas collections)

Total: 23 collections each including a single occurrence

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Specimen images are retrieved through the ePANDDA API.

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