Busycon perversum mm 200 Extra Large Seashell Gastropoda Sea Snail Busycon Whelks Sinistrofulgur Busyconidae (2)

usycon perversum Big Size Extralarge mm 200 Seashell Gastropoda Sea Snail Busycon Whelks Sinistrofulgur Busyconidae, laevogyrous (left opening), unique piece, as in pictures.
Family: Busyconidae (Busycon Whelks).
Common name: The Lightning Whelk.
Syn. Sinistrofulgur perversum, Pyrula kieneri, Fulgur gibbosum, Murex perversus.

There has been some disagreement about the correct scientific name for this species, which has been confused with Sinistrofulgur sinistrum (Hollister, 1958), and Busycon contrarium (Conrad, 1840), which is an exclusively fossil species.
This species also shares many characteristics with another species, the knobby whelk (Busycon carica), but has some important differences: fulcrum whelks coil in a sinistral position, while knobby whelks are dextral; they also have a shallower whorl than the knobby whelk, and their protuberances are usually less developed than the latter. Finally, fulcrum whelks are diurnal, while knobby whelks are active both day and night, and prefer to remain in deeper water than knobby whelks when feeding on muddy bottoms.