Nesonektris aldridgei is an extinct vetulicolian from the Late Botomian-aged Emu Bay Shale Lagerstätte[1] in Kangaroo Island, Australia.

The exquisitely preserved fossils show that running the length inside the tail was a notochord, thereby demonstrating the animal's chordate affinities as being related to tunicates.

[5] A phylogenetic analysis by the discoverers of Nesonektris placed Vetulicolia as the sister-group of Tunicata, but was unable to resolve any internal relationships within the group:[6] Vetulicola† Beidazoon† Ooedigera† Pomatrum† / Xidazoon† Didazoon† Yuyuanozoon† Banffia† Heteromorphus† Nesonektris† Tunicata However, several trees used to produce the cladogram above placed Nesonektris as an intermediate form between Banffia-type and Vetulicola-type forms,[6] and a 2024 phylogenetic analysis agreed with that placement.

Nesonektris is shown as the basal-most member of a paraphyletic vetulicolidan grade, crownward from Banffozoa but outside of either Vetulicolidae (labeled based on Li et al. 2018)[2] or Didazoonidae.

This study recovered Vetulicolia as a basal evolutionary grade along the chordate stem, rather than next to the tunicates:[7] Banffia† Heteromorphus† Skeemella† Nesonektris† Vetulicolidae† Didazoon† Pomatrum† Yuyuanozoon† Yunnanozoon† Cathaymyrus† Pikaia† Chordata(crown group)