PlantFiles: Mojave Prickly Pear, Tulip Prickly Pear, New Mexico Prickly Pear
Opuntia phaeacantha

Dunno where you guys get your common names from but this cactus is known BY none of those names and a search for the Binomal name comes up with nothing.

These are found around the BCC and hybridize easily with O. engelmannii. It's hard to tell all the hybrids apart but generally O, engelmannii has pale yellow to bright yellow flowers. O. phaeacantha has yellow flowers with bright red...
Orange flowered ones are usually O. engelmannii AND should not be considered a hybrid between O. engelmannii and O. phaeacantha

This is the staple of any hardy Opuntia garden. Tolerates some winter wet, but leaves will spot if moisture collects on them for a prolonged period of time. The plant is rather "clunky" and dumpy, but the large flowers (in plum, brilliant red, etc.) are attractive. Unfortunately, each only lasts one day.

I live in Cornwall, UK, zone 9b. Opuntia phaeacantha and some other Opuntia species are perhaps the most surprisingly successful of all the unusual succulents we can grow in our gloomy cool wet climate.

I have grown these plants in zone 8b too, and they have never suffered any damage at all -- even in the wettest, coldest winters. They do not even seem to need special soil, as long as it is reasonably well-drained.

'Experts' still insist that Opuntia humifusa is the only species which can be grown in the UK, but this is just not true. I have grown four large species (unidentified) for twenty years now, and they have been highly successful -- even in really bad winters. Their only enemies are snails which leave greyish brown scars, but the species with closely spaced spines are almost immune from attack.

Definitely worth growing alongside Aloe striatula, Sedum confusum, Delosperma cooperi and Yuccas for a hardy desert garden.

The larger species cannot be relied upon to flower, but O humifusa flowers very profusely.

I love this cactus. A friend dug it up for me from his son's yard in Albuquerque as it was being run over with the lawnmower and he hated it and thought of it as a pest. It has creamy light yellow flowers and gets pretty pink pears. I think of it as a rescue cactus. It's got great spines.

The flowers are fairly attractive, and the fruit (tuna) are one of the popular species for making jams & jellies.
There are about 10 semi-accepted varieties in the U.S. & about 7 in Mexico, much research needs to be done to determine which ones will become official. I have not a guide to any of the varieties, if any one has one, let me know.
One of the common names for the varieties is "Yellow-spined prickly pear" which could possibly be the ones I have posted picts of.

This is a child hood nightmare cactus... all over the southwest (very cold hardy- often lives in climates where it snows 1/3 of the year). Can't recall the number of times I've had to pull spines out from this plant. Not that attractive, either.