The group of taxa that have fully developed appendages can be best described as: Convergent evolution Monophyletic A species Polyphyletic Solution A.convergent evolution. Note- convergent evolution is evolution of similar feature or characters in sDifferent species. These structures are analogous structure which have similar form and function but are not present in last common ancestors. Here appendages are similar feature which different taxas has evolved independentally, and have similar functions..