Case in point!

Perhaps the best find from Japan so far - sakebambaspis!

A nice find from the beach this evening - a lovely shell I didn't recognise (common piddock?) with an encrusting bryozoan colony on the external and internal surface.

When visiting the Natural History Museum, London, I came across a specimen of Pahvanticystis misidentified as Castericystis. On closer inspection, it was clear that there were three juveniles attached to the adult! One of them even has a preserved periproct (anus) 🫣

Coleicarpus stayed attached to the seafloor all its life, while Castericystis was only attached as a juvenile. Another solute is known from House Range – Pahvanticystis – which resembles Castericystis. No fossils of Pahvanticystis show attachment, but its babies are predicted to have been attached.

The earliest known solutes are sometimes found with juveniles attached to them, probably a means to keep safe in the dangerous Anomalocaris-filled middle Cambrian. This behaviour is known in the two oldest solutes, Coleicarpus and Castericystis, from House Range, Utah (~500-510 million years ago).

Very excited to share my first paper – published in Acta Palaeontologica Polonica with @imranrahman.bsky.social about a weird juvenile behavioural character of some early non-radial echinoderms (solutes). A 🧵for a bit more context about why this is exciting!
www.app.pan.pl/article/item...