ぼくとしては、「16へぇ」くらいを押したいトリビアでした(笑)
一応パイナップル餡のヤツもあるそうなのですが、だいたいが冬瓜、もしくは冬瓜とパイナップルの比率半々だそうです。
おいしけりゃええんや！
うぐいす餡にもウグイス入ってないですしね！

This trivia was worth about "16 'Wow's'":https://en.wikipedia.org/wiki/Hey!_Spring_of_Trivia to me. :-)

So far as it goes, I hear there's also pineapple bean paste, but it's all pretty much winter melon, or a half-and-half of winter melon and pineapple, it seems.

So long's it's tasty, ain't no big deal!

There's no nightingale in uguisu bean jam, either, is there! It's actually so named because it's the same greenish-brown color as a Japanese nightingale/[i]uguisu[/i].