Astrodapsis davisi Grant & Eaton, 1941

Davis’ sand dollar

Description: Test is moderately large, somewhat elongate and subpentagonal or rounded subpentagonal. The margin of the test is of moderate thickness. The petals may be moderately raised. The ambulacral groves on the lower surface are slightly depressed, while the areas between the groves are flat or gently arched.

Size: 50-55 mm (greatest diameter) and 40-45 mm (shortest diameter).

Ecology: Nearshore and innermost shelf (5-15 m water depth), often in association with tidal currents.

Geological range: Late Miocene (12-5 million years ago).

Geographic distribution: California. Reported from the Neroly Formation (Miocene). Unconfirmed report from the Santa Margarita Formation (Miocene-Pliocene).

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