Phreatogammarus Helmsii
When he realised that he had mis-sexed his Mount Anglem specimen of P. propinquus, Chilton also realised that the material he had described under that name from Rona Bay, Wellington, was a third species, which he named P. helmsii in 1918. It is a coastal freshwater species, only occurring further inland near Hamilton on the Waikato River system. It is widespread, occurring in many parts of both the North and South Islands.
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