(Original description) The small, acute shell has a sinusigera protoconch, and seven or eight reticulated, full and rounded whorls.

These are crossed by (on the fourth whorl) four, or (on the body whorl) about twenty-five close-set rounded threads, with a tendency to form a little nodule where they cross the summit of the transverse ribs, and pretty even in size.

The first one forms a smooth margin to the narrow, but well-defined notch-band, which is crossed by the lines of growth deeply waved, and extends to the suture, which is not appressed.

The outer lip is thin, much produced forward, as in Daphnella, but the notch is distinct and very deep, with its edges simple and not reflected.

[2] R. morra can be found in Atlantic waters, ranging from the coast of North Carolina south to Brazil.