Fewest eggs per spawning for a frog or toad

The frog or toad species laying the least eggs per spawning is the yellow-striped pygmy frog Eleutherodactylus [formerly Euhyas] limbatus, indigenous to Cuba. The female has only a single ovary and lays just a single egg each spawning, but whereas species that lay a lot more often take no care of them afterwards, the female of this species carefully buries her single egg to ensure that it remains protected while it develops. This tiny species, measuring as little as 8.5 mm long and therefore possibly the fifth smallest frog in the world, has a very fragmented distribution on Cuba and is categorised as Vulnerable by the IUCN.