Abada

Abada are two-horned unicorn-like creatures from central African mythology. In MLP they live in Farasi, Zecora's homeland, and appear exclusively in the Season 10 comics.

They are taller than ponies and, like many horned creatures, can do magic. They are one of the few non-pony species to have Cutie Marks, explained by their magic being inherent versus someone like Zecora the zebra who has to do magic through external assistance.

While not many Abada are seen, most of them appear to have standard hair manes and tails. But one Abada, Dust Devil, has what looks like fins. I don't know if they are supposed to be fins or are just stylistic representations of spiky hair. Here's a fun little fact though, Dust Devil was the first nonbinary character in the entire franchise!