Aside from the problematic PERSON@1 , the first definitive members of the phylum appeared near the start of the MISC@1 period The phylum contains about NUMBER@1 living species , making it the second-largest grouping of deuterostomes , after the chordates ; they are also the largest phylum that has no freshwater or terrestrial representatives .

MISC@2 is the largest animal phylum which has no freshwater or terrestrial representatives .
