wait, frogs have FOUR fingers?? not FIVE?????????
Correct. Frogs and caudates (newts and salamanders). Ancestrally. It looks like the fifth digit was lost among at least one lineage of fairly early temnospondyls, which later gave rise to neobatrachia. But honestly the fossil record is a bit hard to interpret in this regard, and I’m dissatisfied with the work I’ve seen so far.