Shell solid, compact, turgid, pale brown, of about six whorls: apex defective; whorls rounded, with suture inconspicuous, in front of it sloping gently, with two or three prominent spiral cords separated by wider spirally threaded interspaces; the middle of the whorls with three prominent spiral ridges, the base with ten or twelve less prominent spirals, all with wider, evenly threaded interspaces; the spiral sculpture crossed only by lines or irregularities of growth; the absence of any marked shoulder to the whorls is conspicuous; aperture semilunar; outer lip moderately thickened, not relfected ; pillar and body with a moderate layer of callus; the depth of the throat, the outer lip at the margin, and the pillar tinged with purplish brown, the rest white; pillar slightly tortuous, not pervious; canal very short, wide, slightly recurved, with a moderate fasciole. Long. of shell (decollate, leaving four whorls), 104 mm.; of last whorl, 80 mm.; of aperture 62 mm.; maximum diameter of shell 60 mm; of aperture, 32 mm. The total length was originally about 110 mm.

Original description: Chrysodomus oncodes Dall, 1907: 155. Taxonomic history: The name Neptunea oncoda, as interpreted by Tiba & Kosuge (1988: 17-61, figs. 2-5), was erroneously used for a number of shells belonging to other species, among which were aberrant Neptunea lyrata and subadult Neptunea aurigena apeliota n. subsp. Type material: Holotype in USNM 111483. Type locality: "Albatross" st. 4804, Sea of Okhotsk, - 229 fathoms. Description: Size medium for the genus (up to 111.1 mm). Shell thick, solid. Colour orange brown. Shape oval. Upper spire whorls with 2 thick primary spiral cords. Interspaces gradually becoming broader with a rather strong secondary spiral cord appearing. Penultimate whorl with 4 rather weak primary spiral cords, triangular in profile. Secondary spiral cords gradually becoming broad, almost as strong as primary spiral cords on penultimate whorl. Body whorl covered with numerous flattened spiral cords of unequal strength, some secondary spiral cords fine, some as strong as primary. Subsutural slope straight, with numerous fine spiral cords of unequal strength, 2 of them stronger especially on upper spire whorls. Range and habitat: Known from the Sea of Okhotsk only. Comparison: Neptunea oncoda is characterized by the rather oval shape, the straight subsutural slope with 2 stronger secondary spiral cords and the presence of a dense spiral sculpture. Neptunea oncoda is a rare species and the shell which is figured in this book was the only additional specimen we had available for study beside the holotype.

Remarkable among the species of the liratus group, to which it belongs, by the absence of any shoulder to the whorl and the inconspicuous suture. Neptúnea oncoda is characterized by the rather oval shape, the straight subsutural slope with 2 stronger secondary spiral cords and the presence of a dense spiral sculpture.

Okhotsk Sea