Around 4m long (~13′), it had a long snout lined with small sharp teeth – unlike modern beaked whales which are mostly toothless – and much like its close relative Messapicetus it probably led a more dolphin-like lifestyle feeding on small fish near the surface.

It’s currently the youngest known example of a long-snouted stem beaked whale, a holdover from a time when these cetaceans were much more ecologically diverse than they are today.

References:

• Bianucci, Giovanni, et al. “New beaked whales from the late Miocene of Peru and evidence for convergent evolution in stem and crown Ziphiidae (Cetacea, Odontoceti).” PeerJ 4 (2016): e2479. https://doi.org/10.7717/peerj.2479
• Post, K., Bosselaers, M., & Munsterman, D. “A new longirostrine beaked whale Flandriacetus gijseni Gen. et sp. nov. (Ziphiidae, Cetacea, Mammalia) from the Tortonian of the North Sea Basin.” Deinsea 23 (2025): 1-31. https://doi.org/10.5281/zenodo.17880020
• Ramassamy, Benjamin, et al. “Description of the skeleton of the fossil beaked whale Messapicetus gregarius: searching potential proxies for deep-diving abilities.” Fossil Record 21.1 (2018): 11-32. https://doi.org/10.5194/fr-21-11-2018
• Wikipedia contributors. “Beaked whale” Wikipedia, 16 Oct. 2025, https://en.wikipedia.org/wiki/Beaked_whale

It was either part of an early evolutionary branch of the titanosaurs, or at least very closely related to them.

Growing up to around 15m long (~50′), it’s represented by multiple specimens of varying ages, including one of the most complete individual necks of any sauropod. Unlike later-diverging titanosaurs it still had thumb claws on its hands, and it’s unclear if it had any osteoderm armor.

A patch of preserved skin shows polygonal scales with a rough bumpy surface texture — but based on what’s now known from other types of sauropod it probably had a variety of other scale shapes and sizes across different regions of its body.

Recent discoveries of titanosaurian footprints in Mongolia also suggest that the large claws on these sauropods’ hind feet were mostly buried in soft tissue, with only the tips visible in life.

Fossilized gut contents in one specimen indicate Diamantinasaurus was a generalist herbivore eating a wide range of plant species, browsing from low to high foliage heights, and swallowing its bites without chewing. This particular individual wasn’t fully grown, however, and so it may have been in the process of transitioning from a low-level “juvenile” diet to a higher-level “adult” one.

References:

• Bell, Phil R., et al. “Remarkable soft tissue anatomy recorded in titanosaur (Sauropoda) tracks from the latest Cretaceous of Mongolia.” Zoological Journal of the Linnean Society 204.3 (2025): zlaf053. https://doi.org/10.1093/zoolinnean/zlaf053
• Gallagher, Tess, Jason Poole, and Jason P. Schein. “Evidence of integumentary scale diversity in the late Jurassic sauropod Diplodocus sp. from the Mother’s Day Quarry, Montana.” PeerJ 9 (2021): e11202. https://doi.org/10.7717/peerj.11202
• Poropat, Stephen F., et al. “A nearly complete skull of the sauropod dinosaur Diamantinasaurus matildae from the Upper Cretaceous Winton Formation of Australia and implications for the early evolution of titanosaurs.” Royal Society Open Science 10.4 (2023): 221618. https://doi.org/10.1098/rsos.221618
• Poropat, Stephen F., et al. “Fossilized gut contents elucidate the feeding habits of sauropod dinosaurs.” Current Biology 35.11 (2025): 2597-2613. https://doi.org/10.1016/j.cub.2025.04.053
• Taylor, Michael P. “Almost all known sauropod necks are incomplete and distorted.” PeerJ 10 (2022): e12810. https://doi.org/10.7717/peerj.12810
• Wikipedia contributors. “Diamantinasaurus” Wikipedia, 30 Oct. 2025, https://en.wikipedia.org/wiki/Diamantinasaurus

About 1.5m long (~5′), it had very high-set and sideways projecting eye sockets similar to those of modern hippos, indicating it probably had a similar sort of semi-aquatic lifestyle. The shape of its skull also suggests it may have had a short tapir-like trunk.

Much like modern hippos or capybaras Postschizotherium probably spent much of its time wallowing in bodies of water, and emerging onto land to graze on grasses. Its habitat would have been humid forest and grasslands, alongside other animals such as large horses and bovines, one of the last chalicotheres, woolly rhinos, beavers, macaques, bears, big cats, early lynxes, and scimitar-toothed cats.

References:

• Wikipedia contributors. “Postschizotherium” Wikipedia, 08 Nov. 2025, https://en.wikipedia.org/wiki/Postschizotherium
• Xing, Lu-Da, et al. “The first cranium of Postschizotherium (Pliohyracidae, Hyracoidea) from the Lower Pleistocene of China.” Palaeoworld (2025): 200998. https://doi.org/10.1016/j.palwor.2025.200998
• Zan, Jinbo, et al. “Palaeoenvironmental and chronological constraints on the Early Pleistocene mammal fauna from loess deposits in the Linxia Basin, NE Tibetan Plateau.” Quaternary Science Reviews 148 (2016): 234-242. https://doi.org/10.1016/j.quascirev.2016.07.026

It was part of an extinct group known as eocrinoids, which were the earliest known echinoderms to develop stalked bodies and specialized feeding appendages — but despite the name and similar body plan, their resemblance to crinoids was due to convergent evolution rather than any direct relation.

Its globular body was only about 5mm in diameter (~0.2″), with a long stalk at least twice that length ending in a small disc that attached it to the substrate. The upper half of its body was dotted with small holes (called epispires) that probably served a respiratory function, and unlike most other eocrinoids it seems to have had just two slender flexible feeding appendages.

It would have been a suspension feeder, using tube feet to catch food particles floating around in the water, then move it down to its mouth positioned at the base of the two “arms”.

References:

• Buitrón-Sánchez, Blanca-Estela, et al. “First record of Ubaghsicystis (Eocrinoidea-Echinodermata) from the Cambrian (Miaolingian, Wuliuan) of Sonora, Mexico: Biostratigraphical and paleoecological considerations.” Revista de Biología Tropical 69 (2021): 51-61. https://doi.org/10.15517/rbt.v69iSuppl.1.46326
• Gil Cid, Dolores, and Patricio Domínguez Alonso. “Ubaghsicystis segurae nov. gen. y sp., nuevo Eocrinoide (Echinodermata) del Cámbrico Medio del Norte de España.” Coloquios de Paleontología 53 (2002): 21-32. https://hdl.handle.net/10261/8449
• Rahman, Imran A., and Samuel Zamora. “Origin and early evolution of echinoderms.” Annual Review of Earth and Planetary Sciences 52 (2024). https://doi.org/10.1146/annurev-earth-031621-113343
• Sumrall, Colin D., and Samuel Zamora. “A columnal-bearing eocrinoid from the Cambrian Burgess Shale (British Columbia, Canada).” Journal of Paleontology 89.2 (2015): 366-368. https://doi.org/10.1017/jpa.2014.54
• Wikipedia contributors. “Eocrinoidea” Wikipedia, 19 Nov. 2025, https://en.wikipedia.org/wiki/Eocrinoidea

About 15cm long (~6″), it had a large hump on its back shaped like a backwards shark fin. Its deep body was wider at the base, giving it a triangular shape when viewed from the front similar to some modern tropical fish – and suggesting it may have had a similar sort of ecology as a slow but highly maneuverable swimmer feeding on small seabed invertebrates.

References:

• Sun, Zuoyu, and Peigang Ni. “Revision of Kyphosichthys grandei Xu & Wu, 2012 from the Middle Triassic of Yunnan Province, South China: implications for phylogenetic interrelationships of ginglymodian fishes.” Journal of Systematic Palaeontology 16.1 (2018): 67-85. https://doi.org/10.1080/14772019.2016.1269049
• Wen, Wen, et al. “A new basal actinopterygian fish from the Anisian (Middle Triassic) of Luoping, Yunnan Province, southwest China.” Acta Palaeontologica Polonica 57.1 (2012): 149-160. https://doi.org/10.4202/app.2010.0089
• Wikipedia contributors. “Luoxiongichthys” Wikipedia, 11 Oct. 2023, https://en.wikipedia.org/wiki/Luoxiongichthys

It’s one of the most basal (“primitive”) pterosaurs currently known, with its long tail lacking the stiffening bony rods seen in other early “rhamphorhynchoid-grade” forms.

It had a wingspan of around 1.2m (~2′), and a bony crest on its snout that grew taller towards the front. Its jaws contained a mix of two different tooth types – a few long pointed teeth and numerous smaller three-pointed teeth – with wear patterns that suggest its diet primarily consisted of hard-shelled invertebrates.

References:

• Dalla Vecchia, Fabio M., et al. “A crested rhamphorhynchoid pterosaur from the Late Triassic of Austria.” Journal of Vertebrate Paleontology 22.1 (2002): 196-199. https://www.jstor.org/stable/4524213
• Dalla Vecchia, Fabio M. “The first Italian specimen of Austriadactylus cristatus (Diapsida, Pterosauria) from the Norian (Upper Triassic) of the carnic Prealps.” Rivista Italiana di Paleontologia e Stratigrafia 115.3 (2009): 291-304. https://doi.org/10.13130/2039-4942/6385
• Wikipedia contributors. “Austriadactylus” Wikipedia, 26 Sep. 2025, https://en.wikipedia.org/wiki/Austriadactylus

Known from a partial skeleton about 12.7m long (~42′), it was much larger than earlier balaenids, but smaller than modern forms. It also had a narrower flipper shape compared to its modern relatives, a less arched jaw, and its neck vertebrae were only partially fused.

Modern right whales are slow-swimming ram feeders, but since Megabalaena was less specialized for this particular filter feeding style it’s unclear what its ecology was.

References:

• Buono, Mónica R., et al. “The early Miocene balaenid Morenocetus parvus from Patagonia (Argentina) and the evolution of right whales.” PeerJ 5 (2017): e4148. https://doi.org/10.7717/peerj.4148
• Tanaka, Yoshihiro, et al. “A new member of a large and archaic balaenid from the Late Miocene of Sapporo, Hokkaido, Japan partly fills a gap of right whale evolution.” Palaeontologia Electronica 28.2 (2025): 1-59. https://doi.org/10.26879/1549
• Wikipedia contributors. “Megabalaena” Wikipedia, 24 Aug. 2025, https://en.wikipedia.org/wiki/Megabalaena

Known only from incomplete skull material, it had a thin bony crest on its forehead and a long snout with unusually toothless jaw tips — which had a rough bone texture suggesting there was a small keratinous beak there.

Its full body proportions aren’t known, but since its skull measured around 50cm (~1’8″) it was probably at least 2.5-3m long (~8-10′).

When its fossil remains were first discovered in the mid-20^th century it was thought to be a dicynodont-like anomodont, but later examination in the 1990s suggested it was actually a more basal “pelycosaur-grade” synapsid, possibly a sphenacodont close to early therapsids. There hasn’t been any further study on Dimacrodon since then, though, so its exact evolutionary relationships remain very murky.

Its ecology is equally unclear, but its beak-like jaws suggest it may have been somewhat herbivorous. It would have lived around a coastal river delta in a semi-arid climate, alongside herbivorous caseids like Cotylorhynchus and Angelosaurus, predatory sphenacodontids like Dimetrodon, small lizard-like parareptiles and captorhinids, and aquatic temnospondyl amphibians.

References:

• Laurin, Michel, and Robert W. Hook. “The age of North America’s youngest Paleozoic continental vertebrates: a review of data from the Middle Permian Pease River (Texas) and El Reno (Oklahoma) Groups.” Bulletin de la Société Géologique de France 193.1 (2022). https://doi.org/10.1051/bsgf/2022007
• Olson, Everett C., and James R. Beerbower. “The San Angelo formation, Permian of Texas, and its vertebrates.” The Journal of Geology 61.5 (1953): 389-423. https://doi.org/10.1086/626109
• Olson, Everett C. “Late Permian terrestrial vertebrates, USA and USSR.” Transactions of the American Philosophical Society 52.2 (1962): 1-224. https://doi.org/10.2307/1005904
• Sidor, C. A., and J. A. Hopson. “The taxonomic status of the Upper Permian eotheriodont therapsids of the San Angelo Formation (Guadalupian), Texas.” Journal of Vertebrate Paleontology. Vol. 15 suppl.3 (1995): 53A. https://doi.org/10.1080/02724634.1995.10011277
• Wikipedia contributors. “Dimacrodon” Wikipedia, 18 Nov. 2024, https://en.wikipedia.org/wiki/Dimacrodon

Around 3m long (~10′), it had fairly large eyes and a long narrow snout lined with small slender pointed teeth.

It was part of the leptonectid family, closely related to other long-snouted forms like Eurhinosaurus. Although currently only represented by a single fossil specimen, it’s actually the most complete ichthyosaur known from the Pliensbachian age of the Early Jurassic.

Preserved gut contents show that it primarily fed on fish, and also that its stomach was positioned on the left side of its body. The fossilized individual also suffered from multiple injuries during its life, including malformed teeth, a fractured clavicle, and avascular necrosis in its upper limb bones. It appears to have died after a bite to the skull from a predator – likely the larger ichthyosaur Temnodontosaurus – and additional bite marks on one hindlimb may be evidence of scavenger activity.

References:

• Lomax, Dean R., Judy A. Massare, and Erin E. Maxwell. “A new long and narrow‐snouted ichthyosaur illuminates a complex faunal turnover during an undersampled Early Jurassic (Pliensbachian) interval.” Papers in Palaeontology 11.5 (2025): e70038. https://doi.org/10.1002/spp2.70038
• Wikipedia contributors. “Leptonectidae” Wikipedia, 12 Oct. 2025, https://en.wikipedia.org/wiki/Leptonectidae
• Wikipedia contributors. “Xiphodracon” Wikipedia, 25 Oct. 2025, https://en.wikipedia.org/wiki/Xiphodracon

Dwoll suggested “a family of creatures that have evolved to look like every letter of the Roman/English alphabet”:

Grafficimex dwolli is a domesticated species of treehopper closely related to the neotropical genus Cladonota.

Its wild ancestor, the now-extinct species Grafficimex ignotus, had an elaborate pronotum “helmet” with a close resemblance to the English letter F. It proved to be surprisingly easy to raise in captivity, being docile around humans and happily using common houseplants such as Monstera as hosts, and it was also quite morphologically variable. Varieties resembling letters such as E, C, and U were quickly developed, and hobbyists began competing to breed more and more new shapes.

Now, after centuries of selective breeding, the English alphabet has been completed, along with a couple of recently-developed breeds with bulbous protrusions that resemble question mark and exclamation mark shapes.

(Breeds resembling the alphabets of other languages are also in development.)

At about 2cm long (~0.8″), Grafficimex dwolli is rather large for a treehopper, and much like the domestic silk moth it has almost entirely lost the ability to fly.

Along with being kept as novelty pets, often carefully lined up on plant stems to spell out amusing messages, these insects are also quite popular with beekeepers – the honeydew produced by Grafficimex nymphs and adults can be harvested by bees to make dark strong-flavored honeydew honey.