One of the many delightful animals in the rocky intertidal is the vermetid snail, Thylacodes squamigerus. Unlike their more typical gastropod relations, the vermetids don’t live in a shell, per se. Instead, they live in a calcareous tube, which forms a loose coil draped over the surface of a rock. The tubes can be up…
Tag: gastropods
Shell dwellers
Intact shells are a limited resource in the rocky intertidal. Snails, of course, build and live in their shells for the duration of their lives. A snail’s body is attached to its shell, so until it dies it is the sole proprietor of the shell. Once the snail dies, though, its shell goes on the…
Emergence
Every summer, like clockwork, my big female whelk lays eggs. She is one of a pair of Kellett’s whelks (Kellettia kellettii) that I inherited from a labmate many years ago now. True whelks of the family Buccinidae are predatory or scavenging snails, and can get pretty big. The female, the larger of the two I…
Trailblazers
Who do you think makes these tracks in the sand? Any guesses? Here’s another photo, taken from farther away to give you a bigger picture of the scale of things. Believe it or not, the maker of these trails is the little black turban snail, Tegula funebralis. They are one of my favorite animals in…
Beginnings and leavings
A few days ago I was in the intertidal with my friend Brenna. This most recent low tide series followed on the heels of some magnificently large swells and it was iffy whether or not we’d be able to get out to where we wanted to do some collecting. Our first day we went up…
Seek and ye shall find
Before Christmas I was invited to speak at one of the monthly public talks hosted by the Seymour Marine Discovery Center. I’m always happy to be asked to speak to students or the public, so my default answer to these requests is “Yes!” Usually for this kind of presentation I get to choose the topic,…
The problem with shells
The Dendronotus veligers are still alive. I’ve been running into the same difficulties I’ve always had when trying to rear nudibranch larvae: hydrophobic shells that tend to get stuck in the surface tension of the water. Larvae that are trapped at the surface can neither swim nor feed. We can pretty easily rear sea urchin…
The veligers are on their way!
Today a lot of my Dendronotus eggs had hatched on their own, swimming through the water as bona fide veliger larvae. Nudibranch larval culture has officially started! These bad boys are much more spherical now–whew!— which makes me think that pointy-shell thing I saw last week was an artifact of their premature hatching. Now they…
Veligers!
The marine gastropods and bivalves go through a larval stage called a veliger. This larva gets its name from the ciliated structure, called a velum, that the animal uses for swimming. Veligers have shells–1 for gastropods and 2 for bivalves–and can withdraw the velum into the shell. Even gastropods that lack shells as adults, such…
Slugs and sex
What better way to start a new blog than to talk about sex? This morning at the Seymour Center I noticed a blob of what looked like nudibranch eggs on the wall of one of the tanks. Looking around for the likely culprit I saw three big nudibranchs on the tank. Ooh, cool! This is…