Nassarius whelks in the aquarium
Other than the algivororous snail species, such as ceriths and trochoids, probably the most commonly traded gastropods are the nassas, Nassarius sp., a genus of dog whelks. Especially in the USA, it is the Caribbean Nassarius vibex that is most widely sold in aquarium stores, though sadly, coldwater species are mistraded either explicitly or implicitly, as N. vibex itself, or as sharing a similar tropical habit. Other species from locations such as Tonga are regularly encountered, although a formal species identification, is rarely if ever attempted. If a whelk is traded as 'super nassarius' or similar, these nassas can be expected to outsize the diminutive N. vibex, which grows to only 2 centimeters, or 3/4 of an inch, at the most.
Nassas are burrowing snails requiring a fine substrate to dig themselves through. Also as members of the whelks or buccinoids, they have a carnivorous nature, although their utilitarian appeal to aquarists, is that unlike most whelks, nassa feeding behavior is stimulated by the decomposition of animal tissues. They are thus obligate scavengers, consuming the leftovers of the meaty foods, that are relished by most reef fish. Seemingly lacking a raptorial nature, or inclination to rasp sessile animals, nassas are thus regarded as reef safe neogastropods.
