A new family of diminutive zooxanthellate zoanthids ( H exacorallia: Z oantharia)

A new family, genus, and species of zooxanthellate macrocnemic zoanthid is described from O kinawa, J apan. The diminutive zoanthid Nanozoanthus harenaceus  sp. nov. occurs in sandy ‘pools’ upon hard substrates in coral reefs. The results of molecular phylogenetic analyses of mitochondrial 16 S ribosomal DNA and cytochrome  c oxidase subunit  I suggests that N anozoanthidae fam. nov. is genetically close to family M icrozoanthidae and I sozoanthus sulcatus at the intrafamily–suborder level. The N anozoanthidae fam. nov. – M icrozoanthidae clade is clearly highly divergent from all other known zoanthid families and from the order A ctiniaria at the suborder level or higher. These results demonstrate that much high‐level (e.g. above genus) diversity remains to be described within the order Z oantharia, and until such work is complete it will be difficult to completely understand their biodiversity. © 2013 The Linnean Society of London