Ulva sapora sp. nov., an abundant tubular species ofUlva(Ulvales) from the tropical Pacific Ocean

:Previously defined by molecular studies undertaken in Japan and Australia as Ulva sp. 3 and in Hawaii as Ulva OTU6, Ulva sapora sp. nov. is described using combined morphological, anatomical, reproductive and molecular studies on 46 specimens from five localities on the tropical and subtropical east Australian coast. Ulva sapora is characterised by its unique internal transcribed spacer sequence and the following combination of characters: the main axis of the unbranched or branched filiform thallus increasing in breadth from the basal to the upper thallus, cells in surface view unordered except for short rows in some areas of the thallus, cells containing a single chloroplast covering half to the whole outer cell wall and containing 2–10 pyrenoids and many starch granules and reproduction by biflagellate zoids exhibiting differing phototactic responses. The new species is the result of the first critical taxonomic appraisal of the species of Ulva of the poorly investigated tropical east Australian marine macroalgal flora. Ulva sapora was the most abundant filiform species of Ulva in the region, accounting for 32% of the specimens collected during the study.