Evolution of naupliar development mapped on a simplified phylogeny of the Malacostraca based on several papers providing partly conflicting phylogenetic results [76, 77].

The figure summarizes the idea supported in this paper, that the naupliar type of development seen in two malacostracan taxa, Euphausiacea and dendrobranchiate decapods (A and B), in essence is primitive for malacostracans and retained, but modified, from earlier in evolution (red line). C-H show other examples of the variation in developmental type in Malacostraca, both of taxa with free-living larvae and direct developers. (C) Early embryonic-like stage of Nebalia longicornis (Leptostraca) (from [78]). (D) Antizoea larva (Stomatopoda). (E) Zoea larva (Brachyura). (F) Late development stage of Tulumella unidens (Thermosbaenacea) (from [14]). (G) Praunus inermis (Mysida) (from [79]). (H) Idotea baltica (Isopoda) (material collected in Denmark by JO). (I) Three examples of non-malacostracan taxa with free living nauplii early in their development (Branchiopoda, Copepoda, and the Cambrian Rehbachiella).