Asexual reproduction was a mode of reproduction by which offspring arose from a single parent, and inherited the genes of that parent only.
Tribbles were hermaphroditic and were capable of reproducing at will. Born pregnant, and with sufficient food, a single tribble could breed in number exponentially, producing a litter of ten in twelve hours time. (TOS: "The Trouble with Tribbles")
Xindi-Insectoids also reproduced asexually. (ENT: "Hatchery")