Stromboidea
Original Description of Ectinochilus olssoni by Clark & Durham, 1946:
- "Shell medium in size; spire acute with 8 or 9 whorls (tip of protoconch broken); first 4 whorls below the broken protoconch, smooth; below this they are sculptured by fine spiral and longitudinal ribbings; sutures of small posterior whorls depressed; those of anterior whorls appressed; whorls gently convex, 4 posterior ones being somewhat more so than others; anterior whorls of spire with 19 or 20 flat-topped spiral ribs, separated by narrow interspaces; some spiral grooved by incised line and appear as 2 ribs; on body whorl, there are about 23 spiral ribs; toward anteriot end these become broader and more prominent; on whorls of spire longitudinal ribs reach from suture to suture and across about half the body whorl, there being 24 ribs on body whorl and about 26 on anterior whorl of spire; on whorls posterior to this, ribs become progressively finer and more numerous; aperture elongate ovate, acute posteriorly, obliquely truncate anteriorly; posterior canal fairly heavy, open; near its posterior end it curves to the right, not reaching apex; outer lip and broad edge of anterior siphonal notch bordered by smooth narrow varix; growth lines indicate presence of stromboid notch on outer lip above anterior siphonal notch, as is characteristic of the genus; inner lip smooth, covered by fairly heavy callus along outer side of which is groove which deepens near anterior end; this callus joins posteriorly with that which forms inner or left side of posterior canal, while that forming outer or right side is continuous with varix of outer lip."
