Dendrasteridae

Diagrammatic oral view of Scutellaster interlineatus, from Durham (1955).

Belongs within: Clypeasteroida.

The Dendrasteridae are a group of sand dollars known from the Pliocene to the present (Durham 1966b).

Characters (from Durham 1966b): Medium-sized to large; petals well developed; anterior petal more widely open than paired petals; interambulacrum 5 discontinuous; interambulacra nearly as wide as ambulacra at ambitus; four genital pores; food grooves bifurcating or trifurcating; periproct inframarginal to supramarginal.

<==Dendrasteridae D66b
    |--Dendraster Agassiz 1847 M89
    |    |--*D. excentricus (Eschscholtz 1831) M89 [=Scutella excentricus M89, Echinarachnius excentricus D66b]
    |    `--D. laevis D66a
    |--Merriamaster Lambert 1911 [incl. Orchophorus Lambert & Thiéry 1914, Twitchellia Lambert 1916] D66b
    |    `--*M. perrini (Weaver 1908) M89 [=Scutella perrini M89; incl. Orchophorus koehleri Lambert & Thiéry 1914 D66b]
    |--Scaphechinus Agassiz 1863 [=Chaetodiscus Lütken 1864] D66b
    |    `--*S. mirabilis Agassiz 1863 M89 [incl. Chaetodiscus scutella Lütken 1864 D66b]
    `--Scutellaster Cragin 1895 [=Anorthoscutum Lambert & Thiéry 1914, Calaster Kew 1920] D66b
         |--*S. interlineatus (Stimpson 1856) M89 (see below for synonymy)
         `--S. oregonensis M89
              |--S. o. oregonensis M89
              `--S. o. major M89

*Scutellaster interlineatus (Stimpson 1856) M89 [=Scutella interlineata M89, *Anorthoscutum interlineatum D66b, *Calaster interlineatus D66b; incl. Scutellaster cretaceus Cragin 1895 D66b]

*Type species of generic name indicated

REFERENCES

[D66a] Durham, J. W. 1966a. Echinoids—ecology and paleoecology. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt U. Echinodermata 3 vol. 1 pp. U257–U265. The Geological Society of America, Inc., and The University of Kansas Press.

[D66b] Durham, J. D. 1966b. Clypeasteroids. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt U. Echinodermata 3 vol. 2 pp. U450–U491. The Geological Society of America, Inc., and The University of Kansas Press.

[M89] Mooi, R. 1989. Living and fossil genera of the Clypeasteroida (Echinoidea: Echinodermata): an illustrated key and annotated checklist. Smithsonian Contributions to Zoology 488: 1–51.