SMITH BAY boat dive.
3-4 of these large tall animals seen in quite strong current @ ~19-20 m depth, on sandy substrate with sparse seagrasses (mainly paddleweed in image but moderate areas of Posidonia and Zostera meadows were nearby, also areas of bare sand ).This habitat commenced a few metres deeper and further from shore than the extensive low profile rock reef bottom type( the reefs were a treasure-trove of marine life biodiversity and were where most of this and other dives were spent.)
1st image cropped from 2nd. (I have left the 2nd photo up because it adds perspective wrt the terrain).
Among cup sponges on a dive.Once known as Turbo jourdani.
Reputedly largest turbo shell (or heaviest?) in southern hemisphere but I am way out of touch here😑
SMITH BAY boat dive from Arriba(catamaran). 3 mediocre pics of the only one of this species I saw,and my ID is provisional only.