ornamentation and with a prominent, mid-whorl spiral ridge||A. brunnea ||Spire tall conical and orange-red color; mantle light black||2.0||4||a||a ||I ||+||+||+|
|A. turriculata||Spire tall and turret shaped; spire light brown to red-brown||1.8||4-1/4||a||a ||I ||-||+||+|
|A. inflata- group||Shell inflated or flat; spire low conical with a large diameter (relative to adult shell size); surface of spire whorls smooth to sculptured with evenly-spaced spiral ridges||A. inflata||Shell inflated; spire low conical with weak to prominent low spiral ridges; spire sutures lack coloration; keel tall with truncate leading edge; keel base brown to yellow-brown||1.5||4-1/4 to 4-1/2||a||c ||I ||-||+||-|
|A. selvagensis||Shell inflated; spire low conical with sculpture ranging from none to well-developed and evenly-spaced low spiral ridges; spire sutures red-brown (magenta); keel base brown to yellow-brown ||2||3-1/2 to 3-3/4 ||a ||c ||I ||+||-||+|
|A. helicinoidea||Shell inflated, with body whorl broadly oval to rounded; keel of low to moderate height and rounded; spire with spiral ridges, moderately variable in expression; spire light purple or yellow to yellow-tan||2||4-1/2 to 4-3/4 ||c||c ||I ||+||+||+|
|A. californiensis||Shell flattened; keel of moderate height with truncate leading edge and a red- to orange-brown base; spire low conical to globular, and smooth; colorless to uniformly or mottled, light yellow, brown or violet||3.5||3-1/4||a||c ||I ||-||+||-|
|A. lesueurii- group||Shell spire very small; after larval metamorphosis, only a single and rapidly-expanding last whorl (teleoconch) is formed ||A. lesueurii||Shell entirely transparent; spire low and conical with prominent (deep) sutures; keel high, truncate||6||2-1/2||b||b ||I ||+||+||+|
|A. oligogyra||Shell faint pink to yellow; spire low and rounded with shallow sutures: keel of moderate height, rounded||3 ||2-1/2||a||b ||I ||+||+||+|
|A. peronii- group||Shell flat, of moderate to large size; radula type II, with bicuspid lateral teeth ||A. peronii||Shell clear, becoming faintly yellow in large specimens; spire low, rounded; keel of moderate height, with a slightly truncated leading edge and a base that changes from clear to dark yellow-brown with age||10||3-1/2 to 3-3/4 ||b||b ||II ||+||+||+|
|A. fragilis||Shell fragile (very thin-walled), transparent and completely colorless; keel tall with a truncate leading edge and a clear base||9||3-1/2||b||b||II ||+||-||-|
|A. rosea||Spire rounded and nearly globular, due to the shallow sutures of first two and one-half whorls; color faintly yellow; species name based on bright pink color of larvae ||5||3-1/2||b||b ||II ||+||+||+|
|A. frontieri||Spire low, with first and second whorls elevated, forming a low cone; distinctive thin, elevated spiral ridge along outer margin of spire whorls; keel tall and rounded; shell clear ||5.5 ||4-1/2||b||b ||II ||-||+||+|
|A. gaudichaudi- group||Shell flat, with a moderately small maximal size; spire shape low conical; radula type I, with monocuspid lateral teeth ||A. gaudichaudi||Spire low conical and surface lacks sculpture; keel of tall, with a truncate leading edge; keel base yellow- or red-brown ||3||3-1/4 to 3-1/2 ||b||b ||I ||+||+||+|
|A. plana||Spire low conical with two low spiral ridges on second and third whorls; spire sutures violet; keel moderately low and rounded, with a yellow- or red-brown base; opercular gyre with spiral row of spines ||4||3-1/2||a||b ||I ||-||+||+|
|A. echinogyra||Spire moderately low conical, slightly tilted relative to the shell plane; spire with prominent spiral ridges and red-violet to red-brown color ||2.5||3-3/4||a||c ||I ||-||+||+|
|A.inclinata- group||Shell spire large, with globose shape, and tilted (inclined) relative to shell plane; spire whorls with shallow sutures and numerous small tubercula; internal spire walls decalcified; inner surfaces of spire whorls with radial lines; keel tall and rounded||A. inclinata||Shell clear to light yellow; tubercula scattered on surface of spire ||6-7||5||b||c ||II ||+||+||+|
|A. tokiokai||Shell light yellow-brow