Original Description of Strombus propegracilior by Dall & Ochsner, 1928, p. 114:
- "Shell solid, of more than seven whorls (apex defective) with a rather acute spire, the last two whorls comprising the bulk of the whole shell; surface smooth except that the whorls carry at the shoulder eight stout, short, radiating spines; suture appressed and undulated, the space between it and the shoulder in front slightly excavated; whorl in front rapidly attenuated, conic, with a strong siphonal fasciole; canal defective but evidently recurved; inner lip smooth, outer lip defective; body with a thin callus; the spines appear on the apical whorls chiefly as nodules. Height of shell, 80+ mm.; of last whorl 65+ mm.; of aperture, 55 mm.; maximum diameter, 45 mm.,not including the spines."
Types: "Holotype: No. 2936. Mus. Calif. Acad. Sci., collected by W.H. Ochsner and Joseph R. Slevin, November 17, 1905"
Stratum typicum: from upper horizon (zone D), on east shore of Indefatigable Island, Galapagos Group. Probably Pliocene."
Locus typicus: Indefatigable Island, Galapagos Group
Strombus propegracilior Dall & Ochsner, 1928, pl. 2, fig. 4
Comment Dall & Ochsner, 1928, p. 114: "This species approaches the recent Strombus gracilior, which ranges from the Gulf of California to Panama Bay."
- W.H. Dall & W.H. Ochsner, 1928. Tertiary and Pleistocene Mollusca from the Galapagos Islands; Proceedings of the California Academy of Sciences, Fourth Series, vol. XVII, no. 4, pp. 89-139, pls. 2-5, Fulltext