10/10/11 11:56 AM
Hmm. I wonder if this might be a case of "splitting the difference"...it has a pelagic phase, so it's probably a B in my book. From your reference -
Like other species of Nerita, N. tessellata copulates at night. The male transfers sperm-filled sacs, called spermatophores, to the female via a gelatinous tube that is extended from the tip of the penis into the mantle cavity of the female (Chislett 1969). Mature females continually carry spermatophores (Chislett 1969). Once the eggs are fertilized, the female deposits them in water-filled depressions of rocks or other sheltered areas around the mean tide level where they are somewhat protected from direct sun exposure until hatching (Hughes1971). The reproductive season seems to be tied somewhat to location. Populations in Florida have been reported to spawn mainly in the summer months (Kolipinski 1964); whereas, those in Barbados are reproductively active year-round (Hughes 1971). Individuals are sexually mature at a length of about 1.7 cm (Kolipinski 1964).
Embryology / Larval Development:
The 1mm long egg capsules of N. tessellata are oval and covered with calcium carbonate bumps (Andrews 1935). Each capsule contains approximately 111 eggs, which hatch after about 21 days (Kolipinski 1964). Like many other mollusks, the checkered nerite reproduces via a planktonic larva called a veliger (Kolipinski 1964). These larvae remain in the water column until they reach the final stage, or pediveliger, at which time they search for a suitable location to settle and metamorphose into juvenile snails. The average female N. tessellata lays about 160 egg capsules per year (Kolipinski 1964).
10/10/11 12:05 PM
I wasn't sure how to determine which class to put it in. The other snails (except conch) were class A so that is the only reason I chose it. You make a good point. Some have stated Nerites are "imposiible" to breed in captivity and that feeling is likely due to the food requirements during the pelagic phase.
10/12/11 07:23 AM
I'm pretty syre those are pics of collinista snails. Would have been cool if they were nerites, but I seriously doubt that nerites would just raise themselves like those did. I still think nerites ought to be on the species list since they regularly lay eggs in home aquariums. If someone figures out a method to get them through the pelagic larvae stage I think it could be done. In my searches I couldn't find any documented success with nerites.