I think I've posted these rushes before but I can't find the forum topic.
The top plant was found at Pakiri beach, north of Auckland. Growing with Ficina nodosa, and has a continuous pith. Juncus acutus / exotic?
The bottom plant was found in Sandspit estuary, also north of Auckland. Growing with Apodasmia similis, also continuous pith. My guess is Juncus krausii? Or could it potentially be Juncus pallidus?