[photo by me. scanning electron micrograph of shell of juvenile blue topsnail calliostoma ligatum.]
i have to apologize for my lack of posting as of late. my thesis is due in a few weeks and i’ve been madly writing, editing figures, pulling out my hair, etc. in order to get it all done! pictured above is a cleaned shell of one of the little goobers (one of the more frustrating goobers) i raised from adult goobers i collected from clover point, here in victoria.
i collected about 30 adult blue topsnails and warmed them up individually in custard cups to spawn eggs/sperm. out of 30 i had 3 males and 4 females successfully spawn! i took sperm from the males, made a sperm slurry and added it to the eggs of the females, then reared the embryos through until they were about two months old in incubators here in our lab at UVic.
the shell pictured above was cleaned with a household bleach dilution (to remove the snail’s tissue), washed with acetone, then air-dried and stuck down on a small stub using a cactus spine held with fine forceps (headache). this shell was approximately 150 µm in length which is 0.15 mm. ugh.
very tedious process, but a very beautiful shell. the polygonal sculpturing on the shell is laid down when the snail is an embryo. once this embryo hatches and swims up to join the plankton, it stops secreting its shell until after metamorphosis, when it resorbs its swimming organ, settles down out of the water column, and it begins crawling with its foot! You can see the resumption of shell secretion in the shell pictured above, marked by the large ridge, followed by the radial ridges formed on the shell (towards the right of the shell).