This is a cactus pear also known as a prickly pear. They are much sweeter when they are riper than the picture seems to indicate. You can tell they are ripe when they have a deep rose color to them and are slightly soft--beware however, the little cactus spines are very fine and you should use a towel to hold it when you remove the fruit "ball" inside. These are very seasonal and often hard to find, let alone expensive. They taste best when chilled.

Also known as "tuna" in Spanish

In Italian, it is called "figadini" (unsure of spelling). They grow wild all over southern Italy and southern California. They can be very sweet are delicious.

Know in Hebrew as a Sabra. This is a very poular fruit there.

Tuna Peruvian

Hi Tammo this is Patrizia :-) I know that fruit very well because Sardinia is full of them! They are called "fichi d'india". Watch out not to eat too many of them, since you'll get a stomach ache!

Prickly Pear.

Definitely a prickly pear. Being in West Texas, I see them all the time.

in itaky they are called "fichi d'india" (indian figs), they're cactus fruits and tipical of sicily