Ammodramus henslowii
Passerellidae
Ammodramus savannarum
Passerellidae
Ammospiza leconteii
Passerellidae
Ammospiza maritima
Passerellidae
Amnicola antipodanum
Amnicolidae
Amnipila pila
Pachychilidae
Ampelisca abdita
Ampeliscidae
Ampelisca agassizi
Ampeliscidae
Ampelisca cristoides
Ampeliscidae
Ampharete americana
Ampharetidae
Amphinaias asperata
Unionidae
Amphinaias pustulosa
Unionidae
Amphiodia trychna
Amphiuridae
Amphioplus coniortodes
Amphiuridae
Amphiura septus
Amphiuridae
Amphiura wurdemanii
Amphiuridae
Amuranodonta kijaensis
Unionidae
Amusium papyraceum
Pectinidae
Amygdalum papyrium
Mytilidae
Anachis floridana
Columbellidae