Gladiolithus striatus sp. nov. (Prymnesiophyceae), a living coccolithophore from the lower photic zone of the Pacific Ocean

During a study of the modern coccolithophore flora in the central and western Pacific, a hitherto undescribed taxon belonging to the genus Gladiolithus Jordan et Chamberlain was recorded. Here, Gladiolithus striatus sp. nov. is described. The new species resembles Gladiolithus flabellatus (Halldal et Markali) Jordan et Chamberlain in the general construction of the coccosphere, but there are differences in coccolith morphology. The major differences are (1) horizontal grooves occur on the external side of the tubular coccoliths; (2) the lepidolith is a rectangular plate with a finely grooved external surface (G. flabellatus has an oval disc with a smooth external surface); and (3) the suture line separating the two platelets of the lepidolith runs diagonally (it runs along the short axis in G. flabellatus).