Gen

Joermungandr bolti, Carboniferous 'amphibian' from Mazon creek. #sciart

Xenacanthus decheni

Day 10 drawing Extinct Aquatic Creatures as part of Ngabuburit activities during Ramadan.

GENYORNIS, from the new video : www.youtube.com/watch?v=pSME... on the Quaternary ❄️ One of many animals of this period shown in there ❄️ #genyornis #paleoart #bird #bigduck #naturalhistory

Small graphite sketch of a Cooper's hawk perched on a tree branch, drawn in a tiny cream sketchbook. The hawk faces left with detailed feather texture and a sharp, watchful eye, rendered in 4B pencil. A hand holds the book with a silver mechanical pencil below.

Train ride to Toronto, tiny sketchbook open. Drew this Cooper's hawk from photos I took near downtown Ottawa. Pentel GraphGear 1000 .5 mm with 4B lead. They can pivot mid air to chase prey through trees. Sketching it felt steadier than the rails. #bird #sciart

野鳥がたくさん描かれたスマホ壁紙用イラスト

壁紙

Pixel art of a scene under the Cambrian sea showing strange alien-like creatures of the Cambrian Period including Vauxia in the foreground, a pinkish-purple Anomalocaris, deep blue Opabinia, violet Nectocaris, bright green Pectocaris, blue-grey Banffia, and Wiwaxia on the rocks in the background.

Theme: The #Weirdness of Cambrian life
#pixelart #pixel_dailies #paleoart
@pixeldailies.bsky.social

added a quick sketch for a friend's presentation - should be easy to determine

I am accumulating piles of a5 charcoal drawings

charcoal drawing of a cave rock wall

charcoal drawing again, this time a cave rock wall mostly done with charcoal pencil

dusk walk

Drawing showing biodiversity from the Carboniferous of Puertollano, which includes plants, arthropods, fish and tetrapods. From left to right, top to bottom: - The giant millipede Arthropleura walking through the forest floor, next to an amphibian (maker of the Puertollanopus tracks) and insects - General view of the swamp landscape, with a volcano erupting in the background - A early synapsid, maker of possible Dimetropus tracks - Pecopteris monyi, leaves of a tree fern - A pair of Acanthodes swimming through vegetation and smaller fish - The temnospondyl Iberospondylus schultzei swimming next to some platysomid fish - Small clam shrimp Euestheria - Two lycophytes Omphalophloios puertollanense next to some swamp creatures - The xenacanth Orthacanthus hunting in the murky waters - Juvenile shark Lissodus hiding from the fish Progyrolepis speciosus - Puertollanichthys richtei, a small fish, swimming through the vegetation

🌴🦈Carboniferous Puertollano🐸🌋
In the lands of La Mancha, fossils from the Late Carboniferous known from old coal mines reveal a tropical coastal swamp ecosystem, rich in aquatic and plant life
#paleoart #FossilFriday #Carboniferous #Puertollano
🧵Thread for additional explanation

digital painting of the sun rising over snow

would you like to buy a book* with all my old paintings in it?
*pdf sorry

I would draw them once more years later, after some fears of becoming the "pinecrab guy"

M. plenovenatrix discovery was followed these last years by several works uncovering an increasing diversity of primitive cambrian chelicerate groups like the mollisoniids (like Mollisonia, Thelxiope, Corcorania) and the habelids (like Sanctacaris, Habelia), all sharing a similar body type of small bottom-dwellers with extending front legs & flappy respiratory appendages. Some of them even coexisted, both Mollisonia, Sanctacaris & Habelia having been found in rocks from the Burgess Shale.

They were far from being apex predators, something that has been noted too for mandibulates (crustaceans, insects, myriapods). It seems that during the Cambrian, modern arthropod groups were small background species, overshadowed by now extinct groups. Chelicerates started to truly diversify only during the Ordovician, a time period usually associated with the rise of a more modern worldwide fauna after the extinction of most of the primitive soft-bodied groups that ruled during the Cambrian. To make it simple, if the Cambrian explosion provided the blueprints for animal evolution, Ordovician’s beginning was when ecological roles truly started to stabilise. In a way, chelicerates were a bit like mammals were before the extinction of the non-avian dinosaurs: a group of small bodied, mainly generalist animals that diversified after new niches opened.

Is this paleoart accurate ? I was bored to always see the same drawing POV for paleoarts of this species, so I tried something new to show how long the body is! The overall coloration was inspired by some shrimps, I thought of how a big & same-colored pygidium could act as a decoy to protect the prosoma. Perspective on big curvy things isn’t my strong suit, so if you tell me that the shape looks weird I won’t be offended at all. I chose this POV so that most of the appendages could be seen.

REFERENCES · Aria C. & Caron J.-B., 2019. A middle Cambrian arthropod with chelicerae and proto-book gills. Nature 573, p. 586–589. · Bolton S.J., Friedrich M. & Sharma P.P., 2026. Mollisonia is probably not an arachnid. Current Biology 36, p. 126–127. · Dunlop J.A. & Lamsdell J.C., 2017. Segmentation and tagmosis in Chelicerata. Arthropod Structure & Development 46, p. 395–418. · Lerosey‐Aubril R., Kimmig J., Pates S., Skabelund J., Weug A. & Ortega‐Hernández J., 2020. New exceptionally preserved panarthropods from the Drumian Wheeler Konservat‐Lagerstätte of the House Range of Utah. Papers in Palaeontology 6, p. 501–531. · Lerosey-Aubril R., Skabelund J., Ortega-Hernández J., 2020. Revision of the mollisoniid chelicerate(?) Thelxiope , with a new species from the middle Cambrian Wheeler Formation of Utah. PeerJ 8, e8879, 29 pp. · O’Flynn R.J., Liu Y., Hou X., Mai H., Yu M., Zhuang S., Williams M., Guo J., Edgecombe G.D., 2023. The early Cambrian Kylinxia zhangi and evolution of the arthropod head. Current Biology 33(18), p. 4006 - 4013. · Palmer D. & Barrett P., 2009. Evolution: The story of Life. Octopus Publishing Group, 368 pp. · Strausfeld N.J., Andrew D.R. & Hirth F., 2025. Cambrian origin of the arachnid brain. Current Biology 35, p. 3777-3785. Colorado Plateau Geosystems Inc., 2023 & 2026. North America & Global Series. In DeepTimeMaps . Online at https://deeptimemaps.com/map-lists-thumbnails/global-series/ & https://deeptimemaps.com/map-lists-thumbnails/north-america/ The ICS international chronostratigraphic chart 2025. Episodes 2025. Online at https://stratigraphy.org/chart

Why Mollisonia is important in understanding chelicerates' evolution is because of what it represent before the group really exploded later in the Ordovician (+the usual drawing auto-feedback & some refs).

Thank you for reading & I’ll see you on the next #Cheliceratime!
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The Mollisonia genus is known through numerous specimens showing internal organs, including the nervous system. Its big eyes and similarities with some arachnid brains indicate it was relying a lot on its vision to hunt and that chelicerates were already active hunters back 500 million years ago. These similarities even led some to claim that the Mollisonia genus could be an arachnid. To make it quick, even tho some similarities are here, this particular claim of being an arachnid didn’t take into account the rest of the body, had several methodological flaws and didn’t take into account the large literature of these last years about how chelicerate evolution isn’t as linear as we thought for centuries. We’ll talk about this in much more detail in a few months, I plan to make an entire post on the topic because my thoughts were corroborated a few days ago by a response that summarized the same things. I won’t elaborate much beyond saying that it’ll be considered here as a basal chelicerate and that an arachnid-like brain may be the default setting among chelicerates.

Mollisonia plenovenatrix lived 505 million years ago during the Miaolingian epoch. Back then, the area that would become the Burgess Shale was underwater and in tropical latitudes. The Burgess shale is known to be a near ancient continental slopes, so M. plenovenatrix may have lived in deep areas of shallow coastal seas. M. plenovenatrix was far from being an apex predator, this role was assigned to way bigger animals like some trilobites, giant lobopods and radiodonts (like Anomalocaris). It was most likely a medium-size hunter (for Cambrian standards, for us it looks small) that roamed across the sea floor in search of food.

So, is Mollisonia plenovenatrix the grandpa of all chelicerates? Absolutely not, far from it in fact! A 2-segmented chelicera, such primitive respiratory organs & a wide fused pygidium at the back are completely incompatible with the morphology modern species could have arisen from. However, the body plan this morphology could have evolved from is really similar to what’s hypothesised to be the ground body plan of euchelicerates. With several other species, it’s part of the mollisoniids, a small order of basal euchelicerates that branched off early from the group that led to modern euchelicerates. The slide also comprise a phylogenetic tree showing mollisonids like M. plenovenatrix as the sister group to all modern euchelicerates (like arachnids & horseshoe crabs), while pycnogonids are an external group to this assemblage

Mollisoniids are a recent addition to the list of chelicerates orders and took shape these last years due to a revision of numerous previously known fossils that shared similar traits with M. plenovenatrix, which allowed to place them among chelicerates. These arthropods appeared to be already widespread by the time the Cambrian explosion faded, and remained present at least to the beginning of the Ordovician.

We continue with details about its internal anatomy (more on that in a few months), when & where it lived and its place among chelicerates, which is kinda special due to how old and "primitive" it is.

#Cheliceratime
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Mollisonia plenovenatrix is an extinct primitive chelicerate species part of the genus Mollisonia, a long-known genus named first in 1912 by Charles Doolittle Walcott in his historical works on the Burgess Shale. This fossiliferous site from the Canadian Yoho National Park is famous for its importance in paleontology’s history, some of the most popular extinct invertebrates like Anomalocaris having been first described from this locality. Mollisonia plenovenatrix itself was named way later in 2019 on new fossils, from the same Burgess Shale, that showed its chelicerate affinities.

M. plenovenatrix was a small (2,5-3 cm long) arthropod with a long body known by a large number of specimens, 49 being mentioned as of 2019. The body was already subdivided like it is with arachnids & horseshoe crabs into a shielded prosoma, bearing numerous pointy appendages, and then an opisthosoma that made up most of the body length, ending with a flattened broad part and with multiple respiratory organs. This morphology turned the whole body into one big fin flapping up to down, like shrimps & whales.

The prosoma is protected by a short & domed carapace, with its front part protruding frontward. One cool thing with Mollisonia plenovenatrix is the preservation of various appendages beyond the sole exoskeleton: - What M. plenovenatrix is famous for: the oldest pair of chelicerae in the world as of 2026. They are short & 2-segmented, contrasting a lot with the 3-segmented ones of euchelicerates & the 3 to 5-segmented ones across pycnogonids. - 3 long pairs of pointy legs extending beyond the carapace. - 3 shorter pairs of double legs with sharp bases, probably used to process food. - Huge lateral eyes, housed in a dedicated cavity in the carapace.

The opisthosoma made up for most of the body length (more than 80%), and just like before, one cool thing with Mollisonia plenovenatrix is the preservation of various appendages beyond the multispined exoskeleton: - Most of the length is taken by 7 free articulated segments. - The fossil was well-preserved enough to see a bit of its internal organs, like its digestive tract. - Each segment bears a pair of flappy appendages that are the external part of the legs. They most likely represent a transitional stage between the primitive arthropods’ gills and the more derived gills of horseshoe crabs & eurypterids. - The last 4 segments are fused into a broad part called “pygidium” (no link to trilobites’ pygidium, it’s just the same name).

First, thanks to how well its fossils are preserved, there's a lot to say about its morphology! (+ a lil' bit about its discovery)

#Cheliceratime
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This Burgess Shale criter is one of the oldest confirmed chelicerate, and the oldest as of date to show clear recognizable chelicerae. Fossilization of numerous non-mineralised tissues allowed scientists to study this arthropod in a lot of detail. Size : 2,5 to 3cm of body length Time period : Late Cambrian Paleoart speculativometer : Few missing details The animal drawn looks like a shrimp with a short, round & domed head without antennae

What time is it? It’s #Cheliceratime & #Fossilfriday!
For this entry we're talking about one of the oldest chelicerate, Mollisonia plenovenatrix!

All the basic infos are here but if you want to learn more, there’s more below!⬇️

#arthropod #cambrian #paleoart #sciart #bugsky #invert
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Helicoprion

Day 7 drawing Extinct Aquatic Creatures as part of Ngabuburit activities during Ramadan.

a pair of female eurasian bullfinches foraging through bushy fields. the finch on the right has some flower seeds in it's mouth.

a couple of female eurasian bullfinches foraging through bushes 🍃 i haven't worked with gouache in a minute, but fell in love all over again with this piece

drawing of bryony vines

drawing of bryony vines

Black Mandrakes

another painting up for grabs! www.mushbeast.com/product/leas...

“The Cordyceps spider”: Taczanowskia waska sp. nov. (Araneae: Araneidae), a new spider species and a novel case of mimicry of an araneopathogenic fungus (Cordycipitaceae: Gibellula ) | ...

An amazing new species of Cordyceps-mimicking spider has just been described from the Ecuadorian Amazon - Taczanowskia waska

www.mapress.com/zt/article/v...

Close-up photographs of a naturally green harvestman (Algidia viridata ssp. bicolor) with a bumpy, textured body that resembles moss or algae. The arachnid's long spiny legs and bumpy body are shown from multiple angles against a blurred green background.

Close-up photographs of a naturally green harvestman (Algidia viridata ssp. bicolor) with a bumpy, textured body that resembles moss or algae. The arachnid's long spiny legs and bumpy body are shown from multiple angles against a blurred green background.

Close-up photographs of a naturally green harvestman (Algidia viridata ssp. bicolor) with a bumpy, textured body that resembles moss or algae. The arachnid's long spiny legs and bumpy body are shown from multiple angles against a blurred green background.

Close-up photographs of a naturally green harvestman (Algidia viridata ssp. bicolor) with a bumpy, textured body that resembles moss or algae. The arachnid's long spiny legs and bumpy body are shown from multiple angles against a blurred green background.

Never miss a chance to get face-to-face with a harvestman.

This is the stunning subspecies Algidia viridata ssp. bicolor, endemic to New Zealand!

Hi! Here’s my painting of an alpine meadow titled “Symbiosis”

Crafted after observing a favorite meadow in the MHNF in OR. for a couple of seasons.

Most of my pieces are a well researched labor of love. Because of AuDHD, I have to be REALLY compelled to follow through!

#artsky #animalart #frogart

A digitally painted portrait of a Utahraptor

Utahraptor

#paleoart #sciart #art #dinosaur

Ceratogaulus
#iceage #paleontology

Everyone is busy creating paleoart of the new spinosaur, but the truth is that a couple of weeks ago, the description of Foskeia was published, a very strange rhabdodontid found in northern Spain that is already one of the smallest dinosaurs

if you really like my drawing you can right click save image it. it's okay.

someone on tumblr is messaging me in the year 2026 to ask if I want to make blockchain nfts 💀

An illustration of a forest underwater, in the Great Lakes shades of blue and green. There are perch swimming in the foreground, and a giant half-hidden sturgeon passes by in the background.

“Under The Lakes, there are forests.”

While we were ferrying across Huron, one of the naturalists on board mentioned this in passing - and it has stuck with me ever since.