Some photos from Last Sunday at Castle Beach in Falmouth. Above, the periwinkle Littorina littorea, which aggregrates in great numbers on the upper shore. Below, three echinoderm cousins: a Cushion star Asterina gibbosa and a little Sea cucumber Pawsonia saxicola with a Brittle star in the background. It was the first time I saw this beautiful colour variant of the Risso’s or Furrowed crab Risso pilipes. More common is the very similar Montagu’s crab Risso hydrophilus, there are usually 5-10 individuals under a single rock. The small ones especially come in a range of colours that make them excellently camouflaged against the pebbles. Next a juvenile Shanny Lipophrys pholis, a detail of a Corkwing wrasse (I could pick it up, that is how low the tide was) and a shot of the beach, showing the versatility of the mzuiko 60mm lens.
Some pics from today at Flushing Beach. Above, a pair of Green shore crabs Carcinus maenas, below two Furrowed crabs Xantho hydrophilus. (I probably should have gone for a whole crab series, as I saw several other common species…) Instead I took loads of random photos, of things that were 150 mm to things that were only 5 mm, with varying success. For instance of a Painted Topshell Calliostoma zizyphinum on the invasive Bryozoan Watersipora subatra. Also the underside of the urchin Psammechinus miliaris, showing its mouth (Aristotle’s Lantern). Photobombing top left is the commensal worm Flabelligera affinis (which I noticed as well the last time I took a version of this picture). Bit random but it was fun practicing. It actually is more difficult to take photos abovewater compared to underwater due to the glistening and the awkward position kneeling on wet gravel/rocks. Next time I might try a tripod (ideally remote flash would be used but I do not think I am going to invest in that). Btw, if you are on instagram, I also post pics as @an_bollenessor.
This weekend I stopped by Castle Beach in Falmouth to release some of my Snakelocks anemones (more about the aquarium in a next post…). Although the weather was bad, of course that did not prevent me from turning over some rocks. My curiosity was rewarded with another new find: a Hairy crab Pilumnus hirtellus. A beautiful little crab which is not uncommon but here it definitely is not as ubiquitous as the Furrowed and Edible crabs:
I also found a Furrowed crab Xantho incisus with unusual coloration (perhaps because it had moulted but I did not check):
The tides were good this weekend and so we went out to Gylly (Gyllyngvase) Beach in Falmouth, specifically the rocks to the west of the beach (I normally go to Castle Beach to the east):
Although the tide was quite low, no special sublittoral species were encountered, but everything time you go out you still see something new. For instance, a newly moulted Furrowed crab, Xantho incisus pink and soft next to its old brown carapace:
There were very many small Blue-rayed limpets Helcion pellucidum (see also here) on the kelp:
The diversity of crabs here in Cornwall is quite high: it is easy to spot more than five species in just a minute of rock pooling. The Furrowed crab Xantho incisus (or X. hydrophilus) has relatively large claws and can do a lot of posturing when disturbed but it is actually quite docile and never pinches hard:
I have only once encountered the small crab Pirimela denticulata (but I must say I have not been looking particularly hard):
The Broad-clawed porcelain crab Porcellana platycheles is extremely common under rocks. I have added a couple to my aquarium when I started but as they just hide under rocks that wasn’t a very smart idea. Months later when re-arranging a rock I found them again so at least they seem to do well in the aquarium: