Common fishhook cactus 
Graham's nipple cactus 
Mammillaria bachmannii 
Mammillaria bombycina 
Mammillaria canelensis 
Mammillaria compressa 
Mammillaria elongata 
Mammillaria geminispina 
Mammillaria magnimamma 
Mammillaria parkinsonii 
Mammillaria standleyi 
Powder Puff Pincushion 
Spiny pincushion cactus 
Woolly Nipple Cactus