In Malaysia, you can find many local tropical fruits such as durian, mangosteen, jackfruit, rambutan, dragon fruit, and etc.. We also import a lot of cold temperate fruits such as apple, orange, grape, kiwi, and etc.. Some of these local fruits are quite interesting in the sense that they have twins of their own. You may be mistaken by their look or taste.
1) Identical twin with slight difference in character: Duku and Langsat
> They came from the same family of Meliaceae. It is not easy to distinguish them, especially when they are put together, and I'm one of those who can't. They have yellowish skin, and taste sweet and sometimes sour-bitter. Duku has thicker skin than langsat, and langsat tend to have more blackish skin in a short period of time.
2) Identical twin with difference in character: Nangka and Cempedak
> They came from the same family of Moraceae. They are interesting in the sense that it is not easy to identify them to the untrained eyes without opening and seeing its flesh. The main difference between them is the texture of its flesh, where cempedak is fibrous, its not easy to be chewed and normally ended up swallowed, while nangka's flesh can be peeled off and bitten easily. Both of them taste the same, but cempedak is much sweeter and creamier. Nangka is sometimes tasteless and has low level of sweetness. Young nangka can be cooked in curry, while cempedak flesh is dipped in flour and fried as a whole. Even the seed is eaten after frying.
3) Near identical twin with same character: Rambutan and Pulasan
> They came from the same family Sapindaceae. The skin is reddish, with rambutan having hair while pulasan has short and blunt spikes. The flesh is white and wrapped around a seed. The flesh have the same look and taste, but pulasan is sweeter and easier to peeled off from the seed. Sometimes, you can only eat part of the flesh of the rambutan because the flesh tends to cling on to the seed. Usually, it is the rambutan flesh that is canned and sold in tin form.