Endemic new cyclostome bryozoans from Spirits Bay, a New Zealand marine‐biodiversity “hotspot”

Abstract

Two notable species of erect cyclostome bryozoans from a nearshore benthic fauna off Spirits Bay, northernmost New Zealand, are described here for the first time. The first, Spiritopora perplexa gen. et sp. nov., is an endemic cerioporine‐grade genus which is abundant in this area. Colonies are characterised by an unusual combination of fixed‐and free‐walled skeletal morphologies: autozooids forming the extensive encrusting colony bases are normally fixed‐walled, whereas those forming the short, bifoliate erect branches are usually free‐walled. The highly distinctive morphology of S. perplexa, very different from any other fossil or Recent cyclostome, together with its success in overgrowing competitors for space, makes its restricted geographical distribution puzzling and highlights the importance of conservation in this area now closed to trawling, Danish seining, and commercial scallop dredging. The second species, Calvetia osheai sp. nov., is less common, and has small, tree‐like colonies. It is the third species assigned to this distinctive cancellate genus, previously known only from Recent of Tierra del Fuego and the Eocene of Antarctica.