Mide aprox. 3.5 cm, cuenta con un par de celipedos, tres pares de patas el último par de patas hacia arriba, cefalotorax, abdomen conformado por cuatro segmentos, torax fraccionado en ocho esternitos toracicos, telson encorvado hacia la parte interna abdominal acompañado por un par de urópodos.

Ovalipes stephensoni (Coarsehand lady crab)

Taxonomy
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda

Key morphological traits:

• Calico spots on the carapace
• Shell is slightly wider than it is long
• 3-5 sharp spines along the edge of the carapace next to each eye

Fun fact: Coarsehand lady crabs mostly eats molluscs, especially Spisula solidissima (Atlantic surf clam).

Barnacles on dying seasnake. I haven't yet found any images, but it does fit the description in Lanchester, W.F. 1902. On the Crustacea collected during the “Skeat Expedition” to the Malay Peninsula. Proceedings of the Zoological Society of London, 1902 (2) 363–381, (371). See also https://inaturalist.ala.org.au/observations/95904678

The tide was rising very rapidly this day. The barnacles host was a very small wavy turban. There were many of the wavy turbans in all sizes scattered throughout the rocky tidepool areas and shoreline. There were also different species of barnacles on many of them. And yes, I know a tripod would have helped the shakiness.
In the posting link below, on a much larger Wavy Turban Snail Megastraea undosa, there were Triangle Barnacles. However the size made little difference to what specie(s) used them for their hosts.
Triangle Barnacles B. trigonus

found this big crab cephalothorax today - i have never seen this species before. it looks like a swimming crab to me. there is a lot of hairy setae all over it. at first i thought it was perhaps achelous spinimanus, but after looking at other observations on inat i think it may be achelous tumidulus

I found more interesting stuff under this one rock than I usually do all day. To start with, this is the first of these I've come across.
The 'veil' was lifted when I first turned the rock, but it quickly dropped down.
Then, check out all the stuff that's living on it's back.
https://www.inaturalist.org/observations/104559299
https://www.inaturalist.org/observations/104559300
https://www.inaturalist.org/observations/104559301

and from the same rock:
https://www.inaturalist.org/observations/104559296
https://www.inaturalist.org/observations/104559297
https://www.inaturalist.org/observations/104559303
https://www.inaturalist.org/observations/104559302
https://www.inaturalist.org/observations/104559304
https://www.inaturalist.org/observations/104559305
https://www.inaturalist.org/observations/104559306

Quite small, diametre of maybe 1cm, several of them, near lots of dried up blue bottles and same colour as tentacles, but didn't seem to be tentacles. It didn't sting. Was soft. Wondered if it was some type of slug with spherical cerata?? or a tunicate? I have no idea.