The Echinoid Directory

Phylogeny and classification

No cladistic analysis of this group has yet been undertaken. However, Mintz (1968, text-fig. 6) did provide an unsupported phylogenetic tree suggesting possible derivation of Spatangoida and Holasteroida from amongst disasteroid taxa.

In the absence of a phylogenetic hypothesis the following pragmatic scheme is used here. It is not clear how many of these families will turn out to be paraphyletic grades.

Family Pygorhytidae Lambert, 1909 [a grade]
Genus Spatocyphus Pomel, 1883
Genus Pygorhytis Pomel, 1883
Genus Pygomalus Pomel, 1883
Family Collyritidae d'Orbigny, 1853
Genus Collyrites Desmoulins, 1853
Genus Cyclolampas Pomel, 1883
Genus Cardiopelta Pomel, 1883
Genus Proholaster Gauthier, 1896
Genus Cardiolampas Pomel, 1883
Family Disasteridae Gras, 1848
Genus Disaster Agassiz, 1835
Family Tithoniidae Solovjev, 1966
Genus Metaporinus Agassiz, 1844
Genus Tithonia Pomel, 1883
Genus Corytha Pomel, 1883
Genus Tetraromania Solovjev, 1971
Family Acrolusiidae Mintz, 1968
Genus Acrolusia Lambert, 1920

The following papers are key sources of primary data on this group:

Jesionek-Szynanska, W. 1963. Echinides irreguliers du Dogger de Pologne. Actes Palaeontologica Polonica 8(3), 293-396.

Mintz, L. W. 1968. Echinoids of the Mesozoic families Collyritidae d'Orbigny, 1853 and Disasteridae Gras, 1848. J ournal of Paleontology 42, 1272-1288.

Solovjev, A. 1971. Late Jurassic and Early Cretaceous disasterids of the USSR. Transactions of the Palaeontological Institute, Academy of Sciences of the USSR 131, 1-120, pls 1-16 [in Russian].