random rock pool pics

The weather has been generally awful so far this year and so I have not been out much. However it is March already so at least a small blog post is in order! There are loads of Worm pipefish Nerophis lumbriciformis around, some of the males carrying eggs (see also the blog header and the ‘about’ section). I found my smallest one yet. Next up a Sea urchin Psammechinus miliaris with what is probably the parasitic (or commensal?) polychaete worm Flabelligera affinis (thanks David Fenwick). After that, a slighlty out of focus shot of the hydroid Candelabrum cocksii. A few of these small individuals were sat under the first rock I turned over; I reckoned they were some type of spoon worm but they are something very different, thanks again David Fenwick, see for his much better photographs of this weird little thing here. Next the Wrinkled rock borer Hiatella arctica with siphon extended and the pretty acorn barnacle Balanus perforatus. Finally a picture of the Strawberry anemone Actinia fragacea, quite common and pretty, but I do not think I have ever posted a picture of it on the blog before. (All pics taken at Castle Beach in Falmouth btw.) I have three in my tank and it is high time for an aquarium update as well. I hope to go out tomorrow and the weekend as the tides are very low so watch this space!IMG_2057IMG_2058IMG_1694IMG_2234IMG_2040IMG_2032IMG_2051

a most peculiar animal

The rock around Falmouth is very soft in places, and when turning over large stones, sometimes they break and reveal interesting things (I have posted previously about the high density of worms in rocks). I recently had another rock crumbling on Castle Beach and I noticed something unusual-looking slipping away in its burrow. A Sipuncula (‘peanut worms’) or Echiura (‘spoon worms’) I thought, something not featured in any old guide anyway, so I browsed David Fenwick’s aphotomarine site where I quickly found the suspect: the Spoon worm Thalassema neptuni. The Echiura are recognised as a separate Phylum in most books, but recent research has revealed that they are not as special as they look: they are actually ‘ordinary’ Annelid worms (see this Open Access paper):

IMG_8621 The diversity of life within rocks is actually quite surprising. I have not taken a good look at all the types of worms yet, but this one stands out: a tiny Green leaf worm Eulalia viridis (looks like a sock puppet):

IMG_8643The boring bivalve Wrinkled rock borer Hiatella arctica (a juvenile):

IMG_8626And even a small Sea cucumber:

IMG_8636 Perhaps I should make a list of all the species living in the rock. Finally, on the rock surface, I sighted a small Sea hare Aplysia punctata for the first time in Cornwall:

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