Oligopygidae

Haimea caillaudi, from here.

Belongs within: Holectypoida.

The Oligopygidae are a group of smaller irregular echinoids known from the Upper Cretaceous to the Oligocene (Wagner & Durham 1966).

Characters (from Wagner & Durham 1966): Small to medium-sized; periproct small; without oral funnel; auricles partially recumbent.

<==Oligopygidae [Oligopyginae] WD66
    |--Oligopygus de Loriol 1887 WD66
    |    `--*O. wetherbyi de Loriol 1887 WD66
    |--Bonaireaster Pijpers 1933 WD66
    |    `--*B. rutteni Pijpers 1933 WD66
    |--Microlampas Cotteau 1889 [=Microsoma Cotteau 1887 non Cotteau 1886] WD66
    |    `--*M. conicus (Cotteau 1887) [=*Microsoma conicum] WD66
    |--Ovulechinus Lambert 1918 WD66
    |    `--*O. pilula Lambert 1918 WD66
    |--Protolampas Lambert 1918 WD66
    |    `--*P. arnaudi (Cotteau 1891) [=Echinolampas arnaudi] WD66
    `--Haimea Michelin 1851 [incl. Pauropygus Arnold & Clark 1927] WD66
         |--*H. caillaudi Michelin 1851 WD66
         `--‘*Pauropygus’ platypetalus Arnold & Clark 1927 WD66

*Type species of generic name indicated

REFERENCES

[WD66] Wagner, C. D., & J. W. Durham. 1966. Holectypoids. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt U. Echinodermata 3 vol. 2 pp. U440–U450. The Geological Society of America, Inc., and The University of Kansas Press.