I picked these two fruit out of the produce section because they were next to each other, and it turns out they are related.
Sort of looks like a comfortable little cucumber on the outside, but inside, it's full of pulp covered seeds sort of like a pomegranate, but less explosive and more mushy. Kind of fun to scoop out, becuase the pulp is totally separate from the skin, attached by three lines of little cords. When you scoop, all the seedy pulp comes out cleanly and easily. It tastes pretty sour, kind of like blackberries, maybe a hint of mulberry, but definitely no raspberryness to it. I think, seeds strained, it would go well with banana in a smoothie.
It turns out that this baseball-sized yellow fruit is passion fruit. Essentially the same arrangement of encapsulated seeds inside as the taxo, but a lot more of them. Much juicier and incredibly fragrant. Sweeter than the taxo, but still with a nice tartness that comes from pulp. The juice that pools in the bottom isn't sour at all. It has the familiar taste from fruit drinks that have passion fruit in them, but it's much more vivid in person. As I eat it, the aroma seems to move around between multiple notes. Absolutely tropical. I think I'll be eating a lot more of these.