Astrodapsis whitneyi Rémond, 1864

Whitney’s sand dollar

Description: Test is medium to large in size, and rounded to subpentagonal. The margin of the test is highly variable (moderately thick to exceedingly thin). moderately thin and occasionally indented between the petals. The upper surface is variable, and maybe either somewhat flattened in the middle of the test or conical. The petals may be flat-topped or rounded, and bordered by ridges. The areas between the ambulacral groves on the lower surface may be depressed.

Size: 35-40 mm (greatest diameter) and 30-35 mm (shortest diameter).

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

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

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

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