They are called Jagctus, or Jagti in groups. They are very rare because it takes a lot of convincing to get a jaguar to mate with a cactus. As of today, 238 scientists have lost their lives and limbs in the pursuit.
The first attempt to make the Jagtus was recorded in 1929 by Horatio Alva Dopson- a visionary biologist who earned a rare feat by having simultaneous restraining orders in effect from the zoo as well as the botanical garden. He was mauled horribly during a public demonstration but recovered in time for his second demonstration where he was killed outright.
This sharply cooled public funding in the project, but the theories persisted and finally in 1992, a team led by Dr. Filo Wernstrom got funding to try again. This is where DARPA came in. DARPA, or Defense Advanced Research Projects Agency, took great interest in the military application of jagti given tensions in the middle east at the time. They envisioned a fully tactical cactus/jaguar hybrid that could deploy in desert and prairie regions. Jagti not only take advantage of natural camouflage, but they are also the last thing the enemy would expect. Just when they think they're safe they've got a jagtus on their a**.
The DARPA funding was all black book so as not to tip off the Chinese that the United States was also working on cat/plant hybrid war machines. This secrecy was famously blown in 1998 during an annual Department of Defense Staff Christmas Party- Just Google "Hillary Clinton, shart, paper towels, and microphone" to get the low down. The global program fell apart in 2000 and the resulting report was filed by the UN Security Council in 2002.
By 2000, there had been numerous successful breeding sessions and the US had an impressive number of Jagti. However, later intelligence would prove that the acceleration of cat/plant hybrids was all for naught. The Chinese had only managed to create a distinct sub-species of cougar- the kind that only attack Asians in lab coats. The Russian program was revealed to be a semi-sentient Lionus Fly Trap, but very few crosses were viable. The only other program of significance was the Polish, but it was widely known since the early 70's that their program had consisted only of a house cat taped to a box.
Thus the great cat/plant arms war ended in 2002. Since then there has been a general halt to research in this area mostly due to insurance costs and lawsuits stemming from injury. The service record of American jagti have been sealed until 2064.
I was there man, where's my parade?
Drat, my cover has been blown. It is I, Professor Wernstrom.... Damn you Homeskillet, you and your college learning have foiled my carelessly constructed ruse! Well, I guess it's back to what I'm good at... alcoholism and crippling depression. sigh :P