Cambrian carrion fall? Here’s something I’ve been working on: a cluster of ~70 mid-Cambrian (500 Ma) fossils from the Wheeler Fm., Utah. It includes 54 individuals of the tiny trilobite Jenkinsonia varga, buried alive while likely feeding near a much larger decaying 🪱. Bon appétit !
Posts by Rudy Lerosey-Aubril
Elrathia kingi is among the most famous trilobites. In the mid-Cambrian Wheeler Fm. (Utah), it reaches densities up to 500 individuals/m². Yet only one specimen associated with exceptional preservation (limbs) was hitherto known. Here is a second, preserving paired club-shaped gut glands.
Merci pour votre article relayant cette découverte.
Meet Megachelicerax cousteaui, a 500myo sea predator that just rewrote the evolutionary history of chelicerates by 20 million years! New study in @nature.com by @cambrianlife.bsky.social Dr. Rudy Lerosey-Aubril and Prof. Javier Ortega-Hernandez
I've been excited about this for days. Today we get a cool Cambrian critter that's the earliest known member of the group that contains spiders, scorpions, mites, and horseshoe crabs today. And its name?
MEGACHELICERAX
Read all about it in my latest newsletter.
A 500-million-year-old fossil of an early relative of spiders, scorpions, and mites offers insights into how this group of arthropods, called chelicerates, evolved. It has clear claws, and is among earliest known example of this feature in chelicerates: spklr.io/63329EysAT
#Palaeontology
Thanks for sharing your enthusiasm about this research.
Delighted to provide a News & Views for the new Cambrian chelicerate described by @cambrianlife.bsky.social & @invertebratepal.bsky.social in @nature.com
www.nature.com/articles/d41... 🧪⚒️
#FossilFriday — 500 Ma bromance? The solute echinoderm Coleicarpus sprinklei (left) attached to Chancelloria eros (right). Wheeler Fm., House Range, Utah.
Multiple examples of trilobite and arthropod gut tracts preserved from Cambrian Weeks Fm.
Some special locations preserve trilobite and arthropod soft tissue digestive systems. The gut tract is highlighted with the element phosphorus.
@cambrianlife.bsky.social described the process in this open access paper: pmc.ncbi.nlm.nih.gov/articles/PMC...
#12DaysofFossils
New Paper by Parry et al., reinterpreting the oldest diverse #jellyfish fauna as sessile polypoid dinomischids 🪼
These findings significantly expand the temporal and geographical range of dinomischids, elucidating their morphological and taphonomic variation.
buff.ly/ERV7P3C
#PaleoSky #Fossils
🚨Deadline alert🚨 Just a few hours left to submit your abstract for GSA Connects 2025 (23:59 Pacific time TONIGHT!). If you want to present your latest paleontological, geochemical, sedimentological, or geobiological research on the Cambrian, session T155 is here for you!
Reminder: the abstract submission deadline for GSA Connects is rapidly approaching! If you'd like to contribute to our multidisciplinary session Evolution of Life in the Cambrian Seas, submit your abstract by 🚨Aug 5🚨. We're all super excited to hear about your latest research 🥸🤔🤠🤓!
🚨Paper alert🚨 Permian bacteria fossilized as rod-shaped pyrite aggregates! A sweet taphonomy-oriented project led by L. Melim. If pyrite aggregates can similarly form in spherical bacteria, how could we distinguish them from extracellularly formed framboids 🤔🤔🤔
doi.org/10.2110/palo...
#FossilFriday Elrathia kingi is one of the most common trilobites in the Cambrian rocks of Utah’s West Desert. Thousands are found yearly—many geologists have one on their fridge. Yet this specimen - first published in 2008 - is the only one I know of that preserves both limbs and gut remains. 🤩
A black & white photo of an enrolled isoteline trilobite. The specimen is viewed from beneath, with the cephalon facing downward -- only a narrow band of the ventral cephalic doublure is exposed at the top of the image, with the median connective suture just visible. The dorsal pygidial shield is broken away, leaving an impression of the ventral doublure as a broad arcuate band with curving parallel terrace ridges. Overlapping thoracic pleurae can be seen on either side of the specimen. Underneath the missing pygidium, the hypostome -- detached from the cephalic doublure -- is revealed from the ventral side. It is of classic isoteline form, with a deep posterior embayment giving a broadly "forked" appearance. Anastomosing terrace ridges are well displayed, running more or less parallel to the lateral margins. The scale bar at the bottom of the image is 20 mm in length.
Enrolled Isotelus latus w dorsal pygidium broken away revealing classic isoteline "forked" #hypostome (ventral "mouth plate") disarticulated from cephalic doublure. Beautiful preservation of fingerprint-like #terrace ridges! #Ordovician (~450 MYA), Lindsay Fm, Colborne, #Ontario 🇨🇦 #TrilobiteTuesday
Another 🚨Paper alert🚨 Everything you ever wanted to know about colony development in graptolithine pterobranchs 🪸 Still much to uncover, but this sums up what we know so far. Enjoy, it is open access 😜
doi.org/10.1111/ede....
Reminder ⚠️ We are organizing a session at GSA Connects 2025 — T155: Evolution of Life in the Cambrian Seas — which aims to bring together paleontologists, sedimentologists, geochemists, and geobiologists working on this remarkable geological period. Submit your abstract by August 5❗
mushroom shaped organism with translucent base
Many may not remember the DENDROGRAMMA mystery! This weird mushroom-shaped thing was described in 2014 as a "new metazoan" of unknown affinities! They were hinting that it might be a new phylum-but THEN 2 years later @drtimohara.bsky.social sequenced it and BOING! BENTHIC
#SIPHONOPHORE!
Time for a long-overdue post—I've got lots to share lately!
Let’s start with a 🚨paper alert 🚨: a great project on the Ediacaran tubicolous taxon Corumbella, masterfully led by @beckerkerber.bsky.social (🙏 thanks Bruno!).
Takeaway: this tube was single-layered and round. doi.org/10.1098/rsos...
🚨Conference alert🚨 L. Tarhan, R. Gaines, @invertebratepal.bsky.social and myself will co-chair session T155 - Evolution of Life in the Cambrian Seas at @geosociety.bsky.social GSA Connects 2025. Contact me if you have any questions about it. Deadline for abstract submission: August 5th.
A very pig butt looking round marble like animal that is pink. Photo by MBARI.
The “front” of a pig butt worm showing tentacles and a round body. Image by MBARI.
The bottom of a pig butt worm showing it’s odd bilateral butt cheeks. Images by MBARI
Scientists first collected a pig butt worm from the dark ocean depths near Monterey, California. The size of marbles, pigbutts are a near complete mystery. Officially described in 2007, scientists aren’t even sure if the pigbutt form is an adult, or just a very very awkward adolescent stage.
That's an amazing harvestman 🤓
As we wind down 2024, we've put together a list of the top #science stories of the year including a few familiar to @nhmu.bsky.social! Follow this link to read more: bit.ly/3DzCo1w
Using RAMAN to explore the preservation of soft-bodied fossils (here Cambrorhytium) from the mid Cambrian Gray Marjum site in Utah.
And myself bsky.app/profile/camb...
bsky.app/profile/beck...
MASSIVELY excited to see Tityus achilles, South America's first #venom spraying #scorpion, finally described in
@zoojlinnsoc.bsky.social !
This new species from #Colombia can spray venom at potential predators, a striking case of convergent #evolution 🧵 (1/n)
academic.oup.com/zoolinnean/a...