Pascahinnites coruscans hawaiensis (Dall, Bartsch & Rehder, 1938)
DALL, W. H., P. BARTSCH & H. A. REHDER. 1938. A manual of the Recent and fossil marine pelecypod mollusks of the Hawaiian Islands. Bernice P. Bishop Museum Bulletin, 153: i-iv, 1-233, pls. 1-58 [p. 88, pl. 22, figs. 5-8]
1938 Chlamys hawaiensis Dall, Bartsch & Rehder, 1938
W. H. Dall, P. Bartsch & H. A. Rehder, 1938, plate 22.
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«Shell small, varying from white to red in different specimens, subequivalved, with the anterior wing strongly developed, and the posterior wing almost completely reduced. The junction of the wing with the central disk forms a decided notch for the byssus in the right valve. In the left valve there is an indentation here which corresponds to the byssal notch of the opposite valve. The wing of the right valve is marked by seven strong radiating cords dorsal to the byssal notch. In addition to that, it bears irregular rough concentric lamellae. The wing of the left valve is also marked by six cords of irregular strength. Both wings are marked by irregular rough
concentric lamellae. The anterior edge of the central disk in the right valve is finely denticulated. The disk proper is marked by 15 strong radiating folds which in turn are marked by strong cords. The median of these cords is usually stronger than those adjacent to it, and as a rule five constitute the ornamentation of the radiating folds. These cords become weakly nodulose on the ventral half of the shell. The spaces separating the folds are about two thirds as wide as the cords, and they are rather coarsely pitted. The interior is porcelaneous. Ligamental area finely transversely denticulated and obscurely longitudinally grooved. The resilial pit is deep in both valves. The central portion is rendered somewhat fluted by the external sculpture and scalloped at the ventral margin. Muscle scar poorly differentiated. The type, U.S.N.M. Cat. No. 484165, was collected by Thaanum (ColI. No. 2066c) on the reef on the Honolulu side of the entrance to the channel to Pearl Harbor, Oahu. It measures: height, 11.3 mm.; length, 9.9 mm.; diameter, 4.3 mm.
U.S.N.M. Cat. No. 337545 contains a topotype from the same source. We have the following additional specimens: U.S.N.M. Cat. No. 337525, 1 specimen collected by Thaanum (ColI. No. 8413) off Pearl Harbor, Oahu, in 12-25 fathoms. U.S.N.M. Cat. No. 337543, 30 specimens collected by Thaanum (ColI. No. 2066a) at the entrance to Honolulu Harbor, Oahu, in 5-8 fathoms. U.S.N.M. Cat. No. 337544, 20 specimens collected by Thaanum (ColI. No. 2066b) off Waikiki, Oahu, in 33-50 fathoms. U.S.N.M. Cat. No. 337542, 8 specimens collected by Thaanum (ColI. No. 2066) at Keokea, Hilo, Hawaii. Of this Mr. Thaanum states: "Mostly on rocks, but a few have been found swimming. Rare." U.S.N.M. Cat. No. 337546, 1 specimen collected by Thaanum (ColI. No. 2066d) off Launiupoko Camp, Maui, in 4-8 fathoms. U.S.N.M. Cat. No. 335567, 1 valve dredged by the D. S. Bureau of Fisheries Steamer Albatross at Station 3837 off the south coast of Molokai, in 13 fathoms on yellow sand; surface temperature 76° F. U.S.N.M. Cat. No. 335676, 1 specimen also dredged by the Albatross at Station 3847 off the south coast of Molokai, in 23-24 fathoms on sand and stone bottom; surface temperature 76° F. U.S.N.M. Cat. No. 337547, 1 specimen collected by Thaanum (ColI. No. 2066e) off Waimea, Kauai. U.S.N.M. Cat. No. 340708, 1 valve collected by Edna Bowen at Hanalei, Kauai. U.S.N.M. Cat. No. 335673, 1 valve dredged by the Albatross at Station 3968 on French Frigate Shoal in 140-160 fathoms on coarse sand and coral bottom; surface temperature 75° F. U.S.N.M. Cat. No. 428486, 4 valves collected on a sand bar on Midway Island by Galtsoff at D. S. Bureau of Fisheries Station 50.» WILLIAM HEALEY DALL, PAUL BARTSCH & HARALD ALFRED REHDER, 1939
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