Authors earlier this century who described such subaerial dunes were not
aware that similar dunes occur underwater in the ocean. Although some
differences have been described that are used by some authors to
distinguish between subaerial dunes and subaqueous dunes (Glenn has
elaborated at length on these), very little work has been done on
subaqueous dunes, and I am certain that the sample size is inadequate to
draw any conclusions on what can or cannot be found in subaqueous dunes.
In any case, the burden of proof is on those who advocate subaerial dunes,
since Brand has described a number of trackways that cannot be expalained
in a subaerial environment without amazing hand waving.