Shell 7-10 mm long, teleoconch whorls seven, profile slightly convex, sutures barely impressed; width about one-third length; ivory with narrow, interrupted white band just below suture; sculpture of fine spiral grooves; outer lip strongly denticulate within, parietal wall sometimes with three denticles, anterior callus protruding slightly. Protoconch broken in all specimens investigated, but appearing multi-whorled, with shallow velar sinus.

Aesopus chrysalloides Carpenter, 1886 Proceedings of the California Academy of Sciences, 3:223. Arnold, Paleontology of San Pedro, California; Pl. 5, fig. 8. A. t. parva, eleganter, effusa, marginibus spirae utrinque excurvatis ; albida, rufofusco concinne punctata seu tincta; interdum striga albida sub- suturali, rufofusco tesselata; anfr. nucl. 3. laevibus, haud, tumidis, apice declivi; norm. v.t. adolescente planatis, dein tumidioribus, suturis distinctis; tota superficie elegantissime tenuiter sulcata, sulcis aequidistantibus, anfr. penult. circ. xx.; apertura flexuosa subpyriform; canali oblique sinistrorsum truncata, axi quasi umbilicata; labro intus acuto, postice sinuato, deorsum quasi tumidiore, intus 7-dentato; columella torta; labio antice rugis paucioribus interdum munito. Long., 0.37; long. spir., 0.22; lat., 0.14 poll. (Carpenter.) Shell cylindrically oblong, shining, whorls seven, slightly rounded, covered with microscopic spiral lines; yellowish to chocolate; lip scarcely thickened and very slightly dentate within. Length, .8 mm. (Tryon, Manual of Conchology.) TYPE in State Collection, No. 613. Type locality, San Pedro, California. RANGE. San Pedro to San Diego, California. Pleistocene: San Pedro to San Diego, California.

This species is recognizable because it is two or three times larger than other northeast Pacific Aesopus species. Carpenter gave it minimal treatment in 1864 (name only on p. 613 and a one-line description on p. 664), then described it completely in 1866. The few specimens in collections are mostly subfossils, but the description in 1866 reports living specimens on sand at 8 fms. [14,6 m].

Distribution. Santa Monica, Los Angeles County, to San Diego, California; 10-25 m. Uncommon, not collected in recent years.