After Prothero & Schoch, 1989, McKenna & Bell, 1997 and Thewissen, Williams & Hussain, 2001
<==o Helaletidae Osborn, 1892 [paraphyletic?] |?- †Hyrachyus asiaticus |?- †Jhagirilophus chorgalensis Thewissen, Williams & Hussain, 2001 |?- †Triplopus kalakotensis |-- †Helaletes nanus (Marsh, 1871a) [Veragromovia, Chasmotheroides] |-- †Desmatotherium intermedius (Osborn, Scott & Spier, 1878) [Helaletes intermedius] |-- †Selenaletes scopaeus |-- †Dilophodon minusculus Scott, 1883 [Heteraletes] |-- †Haagella |-- †Plesiocolopirus hancocki `--o †Colodon |?- †C. cingulatus |-- †C. kayi |-- †C. woodi `-- †C. occidentalis
Reference(s):
–W. H. Freeman and company, New York, 1988, 698.
in Carroll, R. L., 1988: Vertebrate paleontology and evolution.
–W. H. Freeman and company, New York, 1988, 698.
–Smithsonian Contributions to Paleobiology: No. 26, pp. iv-25
–Columbia University Press, New York, 1997, xii-631
in Prothero, D. R. & Schoch, R. M., (eds.) 1989: The Evolution of Perissodactyls.
–Oxford University Press, New York, New York & Oxford, England, 1989, ix-537
–Journal of Vertebrate Paleontology: Vol. 21, #2, pp. 347-366