Type Locality: Hawaii, Off Waikiki, Oahu, in 33-50 fathoms.
Original Description: "Shell equivalved, subcircular, gibbous, varying in color from white through yellow to orange, unicolor or mottled and variegated. The wings are equally developed and marked by six somewhat irregular radiating cords. The central portion of the rather inflated disk is marked by eight strong broad, moderately elevated, radiating folds which bear large rounded nodules, and which are about twice as broad as the spaces that separate them and which grow less strong laterally. They are marked also by radiating cords which vary in number from five to 12, the larger number being on the central fold. On the lateral margin the folds disappear, but the fine threaded sculpture present on the ribs remains. The depressed areas between the folds are also marked by radiating cords that equal those on the ribs in strength. The anterior and lateral border at the byssal notch is finely denticulated. Interior of the shell rather brilliantly colored; the edge of the shell is yellow, the hinge and the rest of the interior, bright red. The dorsal termination of the ligamental area shows a few slender longitudinal grooves. The resilium is large and triangular. On each side of the resilium in the right valve is a pit for the reception of an equivalent tooth in the left valve. This pit is bordered on each side by oblique teeth which in turn have equivalent depressed areas in the opposite valve. This in turn is followed by a deep pit engaging the strong tooth in the opposite valve and then by a big heavy tooth which has its equivalent depression in the other valve and still another depression for a tooth in the opposite valve. The teeth as well as the rest of the hinge, are finely transversely grooved. The margin of the shell is slightly scalloped and somewhat fluted basally, and its edge rather prominently denticulated." (fide Dall, Bartsch & Rehder, 1938) Size: Normal adult size range is 30 to 35 mm.
Distribution: From the Hawaiian Islands. Habitat: Littoral to sublittoral zones, on sandy bottoms with coral rubble.
Remarks: Some authors consider this to be a synonym of B. nodulifera (G. B. Sowerby II, 1842), however, B. langfordi is much more globose and is restricted to the Hawaiian Islands. Relevant Literature: Dall, Bartsch & Rehder, 1938; Kay, 1979; Dijkstra & Roussy, 1994.