Holospondyli
Holospondyli is a proposed clade of lepospondyls from the Early Carboniferous to the Late Permian that includes the aistopods, the paraphyletic nectrideans, and possibly also Adelospondyli. However, aistopods have since been recovered as stem-tetrapods more primitive than temnospondyls or other groups of lepospondyls.

References

Stegocephalians
Polyphyletic groups