Alejandro Izquierdo López, PhD Profile picture
Evolutionary biologist, PhD @eebtoronto Invertebrate Palaeontology lab @ROMtoronto, Burgess Shale bivalved arthropods. Freelance Scicomm writer, @elephabacteria

Jul 11, 2022, 10 tweets

Although the paper is officially published this Friday, some of you have already found out about it, so I cannot keep it secret any longer. Here is the newest bivalved #arthropod from the Burgess Shale: Balhuticaris voltae. (1/8)

Link: cell.com/iscience/fullt…

Balhuticaris belongs to a group of 500 million-year-old carapace-bearing arthropods known as hymenocarines. We think that hymenocarines are probably early mandibulates, the group that contains crustaceans, myriapods and insects, although there are still some debates about it.

Some hymenocarines have been argued to have a very unspecialized body, more characteristic of what we would expect of the ancestors of all true arthropods. But recent discoveries like Pakucaris and Balhuticaris show an increasingly complex group

Balhuticaris has many striking features. The arch-like carapace is unlike anything we have seen in any other arthropod. We don't really know what its function could have been. The eyes are bilobate, giving Balhuticaris the ability to calculate distances better than its kin.

Another feature is its extreme multisegmentation. Hymenocarines and trilobites can have a huge number of segments, but the 110 of Balhuticaris is a Cambrian record. Only centipedes and millipedes have that many segments. What drove this convergent evolution? We do not know yet.

Understanding its ecology has been a major challenge. We think that Balhuticaris may have collected small prey using water currents, a lifestyle between a suspension feeder and a predator. Similar to Fibulacaris, there is a chance it may have swum upside-down, as well.

Balhuticaris voltae means the arch-like crab of Balhut. Balhut, also known as Bahamut, is a mythological gigantic marine creature in several Islamic medieval cosmographies. At 25 cm Balhuticaris is the largest bivalved arthropod we know, a challenge to predators like Anomalocaris

All the art you have seen is from the talented artist Hugo Salais. You can find his profile here:
metazoastudio.com

Here is an unpublished drawing of two Balhuticaris (we found two specimens very close to each other) by the same author

This research was conducted by myself and Dr.Caron. The work would not have been possible without @MaryamATweets and the @ROMtoronto facilities. The project is also funded by @BecariosFLC

🚨Seems I put the wrong link to see the webpage of the artist Hugo Salais (Sorry Hugo). Here is the correct one:
metazoa.studio/home

Share this Scrolly Tale with your friends.

A Scrolly Tale is a new way to read Twitter threads with a more visually immersive experience.
Discover more beautiful Scrolly Tales like this.

Keep scrolling