Original Description of Struthiolaria spinifera by Marwick, 1924:
- "Shell moderately large, conoidal, with high turreted spire, 1½ times height of aperture; whorls 8, angled above middle with concave shoulder and sloping sides, body-whorl bicarinate, keel of greater diameter than shoulder-angle, base rapidly contracted; apex conoidal, nucleus minute, planorbid; sculpture, first whorls after apex are faintly shouldered, the shoulder-angle of fourth has numerous nodules, while on each of remaining whorls it bears 9 long strong spines, keel of body-whorl also has strong spines, more closely placed but hardly so long as those of shoulder-angle, fine spiral ornamentation is obsolete but growth-lines are strong; suture somewhat undulating, bulging over spines of concealed keel and with narrow strip of callus peeping over it here and there; aperture ovate, subangled above, produced into short canal below; outer lip reflexed, thickened, edge wedge-shaped, sinuous, with fairly prominent projection opposite shoulder-angle and more prominent one opposite keel, inner lip with moderately wide and regular callus just surmounting keel where it joins outer lip; columella concave, bent to right below and ending in beak."
Dimensions Holotype: Height, 55 mm.; diameter, 39.5 mm
Locus typicus: Mount Harris, Canterbury, South Island, New Zealand
Stratum typicum: Otaian, early Miocene