Griffiths, Annual Report of the Missouri Botanical Garden 22: 34, 1911
Opuntia tardospina is a large species first reported from the Lampasas, TX region. Griffiths reported that it is unusual for several reasons. The glochids are numerous and prominent (up to 12 to 15 mm-long even on pads of the current year). Also, areoles are prominent, up to 1 cm across in old growth and raised by 2 to 4 mm. Additionally, spines are mostly absent but some yellow ones do occur that recurve or slope downwards. Finally, the prominent glochids can cover old stems as in the case of O. chlorotica santa-rita. Under favorable conditions (garden), spines may cover the cladodes.
O. tardospina differs from O. aciculata in several ways: the pads are bluer and thicker, and the trunks have glochids. The plants in these photos have curved leaves on the ovaries, which is a feature of O. cacanapa. See the original description.