TRIASSIC AMMONOIDS

CANGREJO FÓSIL: COSTACOPLUMA

Cuticular structure in a Late Maastrichtian crab, Costacopluma mexicana, from deposits near the town of from near Paredón, Ramos Arizpe in what is now southern Coahuila (formerly Coahuila de Zaragoza), north-eastern Mexico. We see this same species in the Upper Cretaceous Moyenne of Northeast Morocco and from the Pacific slope, Paleocene of California, USA. This beauty is in the collection of José F. Ventura‎.

While the crustacean cuticle has been the subject of study for over 250 years (Reaumur, 1712, in Drach, 1939), the focus of that early work has been the process of moulting. Because crabs and other crustaceans have a hard outer shell (the exoskeleton) that does not grow, they must shed their shells through a process called moulting. Just as we outgrow our shoes, crabs outgrow their shells.

In 1984, Roer and Dillaman took a whole new approach, instead looking at the exoskeleton as a mineralized tissue. The integument of decapod crustaceans consists of an outer epicuticle, an exocuticle, an endocuticle and an inner membranous layer underlain by the hypodermis. The outer three layers of the cuticle are calcified.

The mineral is in the form of calcite crystals and amorphous calcium carbonate. In the epicuticle, the mineral is in the form of spherulitic calcite islands surrounded by the lipid-protein matrix. In the exo- and endo-cuticles the calcite crystal aggregates are interspersed with chitin-protein fibres which are organized in lamellae. In some species, the organization of the mineral mirrors that of the organic fibres, but such is not the case in certain cuticular regions in the xanthid crabs.

Control of crystal organization is a complex phenomenon unrelated to the gross morphology of the matrix. Since the cuticle is periodically moulted to allow for growth, this necessitates a bidirectional movement of calcium into the cuticle during post-moult and out during premolt resorption of the cuticle.

These movements are accomplished by active transport affected by a Ca-ATPase and Na/Ca exchange mechanism. The epi- and exo-cuticular layers of the new cuticle are elaborated during pre-moult but do not calcify until the old cuticle is shed. This phenomenon also occurs in vitro in the cuticle devoid of living tissue and implies an alteration of the nucleating sites of the cuticle in the course of the moult.

We're still learning about the relationship between the mineral and the organic components of the cuticle, both regarding the determination of crystal morphology and about nucleation. While the Portunidae offers some knowledge of the mechanisms and pathways for calcium movement, we know nothing concerning the transport of carbonate. These latter areas of investigation will prove fertile ground for future work; work which will provide information not only on the physiology of Crustacea but also on the basic principles of mineralization. I'm interested to see what insights will be revealed in the years to come. Certainly, the bidirectional nature of mineral transport and the sharp temporal transitions in the nucleating ability of the cuticular matrix provide ideal systems in which to study these aspects of calcification.

Torrey Nyborg, Francisco J. Vega and Harry F. Filkorn, Boletín de la Sociedad Geológica Mexicana, Vol. 61, No. 2, Número especial XI Congreso Nacional de Paleontología, Juriquilla 2009 (2009), pp. 203-209. Coahuila paleo coordinates:25°32′26″N 100°57′2″W

BIBONIDAE: LATE BLOOMING POLLINATORS

A recent post of the fossils found at McAbee in the Interior of British Columbia has me thinking of March Flies. March Flies are hardy, medium-sized flies in the Order Diptera, with a body length ranging from 4.0 to 10.0 mm. They tend to make for excellent specimens as they fossilize rather well. This species is one of the most satisfying fossils to collect in the Eocene deposits of McAbee and in the outskirts of Princeton, British Columbia.

The body is black, brown, or rusty, and thickset, with thick legs. The antennae are moniliform. The front tibiae bear large strong spurs or a circlet of spines. The tarsi are five-segmented and bear tarsal claws, pulvilli, and a well-developed empodium. As it is with many species, these guys included, the teens of this species are troublesome but the adults turn out alright. As larvae, Bibionidae is an agricultural pest, devouring all those tasty young seedlings you've just planted.

Then, as they mature their tastes turn to the nectar of flowers from fruit trees and la voila, they become your best friends again. With their physical and behavioural transformation complete, Bibionidae becomes a welcome garden visitor, pulling their weight in the ecosystems they live in by being important pollinators.

AMMONITE CLUSTER

Ammonites have intricate and complex patterns on their shells called sutures. The suture patterns differ across species and tell us what time period the ammonite is from. 

Ammonoidea can be divided into six orders:

Agoniatitida: Lower Devonian - Middle Devonian

Clymeniida: Upper Devonian

Goniatitida: Middle Devonian - Upper Permian

Prolecanitida: Upper Devonian - Upper Triassic

Ceratitida: Upper Permian - Upper Triassic

Ammonitida: Lower Jurassic - Upper Cretaceous

If they are geometric with numerous undivided lobes and saddles and eight lobes around the conch, we refer to their pattern as goniatitic, a characteristic of Paleozoic ammonites. Like other cephalopods, ammonites had sharp, beak-like jaws inside a ring of squid-like tentacles that extended from their shells. They used these tentacles to snare prey — plankton, vegetation, fish and crustaceans — similar to the way a squid or octopus hunt today. Ammonites were skilled and successful hunters. They caught their prey while swimming and floating in the water column. This cluster of ammonites cemented together in death would have hunted our ancient seas as keen predators.

MARINE REPTILES OF THE HUMBOLDTS

A very well preserved ichthyosaur block with three distinct vertebrae and some ribs just peeking out. You can see the edges of the ribs nicely outlined against the matrix.

Ichthyosaurs are an extinct order of marine reptiles from the Mesozoic era. They evolved from land-dwelling, lung-breathing reptiles, they returned to our ancient seas and evolved into the fish-shaped creatures we find in the fossil record today.

They were visibly dolphin-like in appearance but seem to share some other qualities as well. These lovelies were warm-blooded and used their coloration as camouflage. The smaller of their lineage to avoid being eaten and the larger to avoid being seen by prey. Ichthyosaurs also had insulating blubber, a lovely adaptation to keep them warm in cold seas.

Over time, their limbs fully transformed into flippers, sometimes containing a very large number of digits and phalanges. Their flippers tell us they were entirely aquatic as they were not well-designed for use on land. And it was their flippers that first gave us the clue that they gave birth to live young; a hypothesis later confirmed by fossil embryo and wee baby ichy specimens.

We find their fossil remains in outcrops spanning from the mid-Cretaceous to the earliest Triassic. As we look through the fossils, we see a slow evolution in body design moving towards that enjoyed by dolphins and tuna by the Upper Triassic, albeit with a narrower, more pointed snout. During the early Triassic period, ichthyosaurs evolved from a group of unidentified land reptiles that returned to the sea. They were particularly abundant in the later Triassic and early Jurassic periods before being replaced as a premier aquatic predator by another marine reptilian group, the Plesiosauria, in the later Jurassic and Cretaceous periods.

The block you see here is from Middle Triassic (Anisian/Ladinian) outcrops in the West Humboldt Mountains, Nevada.

SUNRISE FORMATION, NEVADA

At the entrance to the Pliensbachian-Toarcian localities at Joker Peak and Mina Peak Members of the Sunrise Formation, Nevada, USA.

The ammonites of this section were first studied by Dr. Paul Smith, past Chair of Earth and Ocean Sciences, University of British Columbia and more recently by Andrew Caruthers et al.

Caruthers and his team also took a goodly look at the Early Jurassic coral fauna. Caruthers is an interesting cat. He uses a combination of invertebrate paleontology and isotope geochemistry to ponder the effects of paleoclimate change and mass extinction. He's turned his eye in recent years to the Paleozoic of the Michigan Basin AND he's based in Kalamazoo, MI. Yep, Kalamazoo.

Others have taken up the mantle of discovery from these sites. Pengfei Hou did his 2014 Masters thesis comparing the Sinemurian (Early Jurassic) stratigraphic sections of Last Creek, British Columbia and Five Card Draw, Nevada including a detailed taxonomic study from the Involutum Zone to the lower part of the Harbledownense Zone of the Sinemurian.

DUBIOUS DAONELLA DUBIA

Triassic ammonoids, West Humboldt Mountains, Nevada, USA. This was the site of the 1905 Expedition of the University of California’s Department of Geology in Berkeley funded by the beautiful and bold, Annie Alexander, the women to whom the UCMP owes both its collection and existence.

Paleontologist J.P. Smith joined that expedition and published on the marine fauna in the early 1900s.

They formed the basis for his monograph on North American Middle Triassic marine invertebrate fauna published in 1914. N. J. Siberling from the US Geological Survey published on these outcrops in 1962. His work included nearly a dozen successive ammonite faunas, many of which were variants on previously described species.

Evidently, his collections consisted mainly of weathered material and were made without stratigraphic control because he believed that most, if not all, of these species, were coexistent. The fossiliferous beds found here, as well as localities in north-western Nevada, were designated the 'Daonella dubia' zone. Dubious would be closer to the truth. We've since mapped them out from stratigraphic sections to place them in the correct order of their occurrence.

SMILODON FATALIS

During the last ice age, huge cats bigger than an African lion prowled Alberta, including the fearsome beast commonly known as the sabre-toothed tiger.

The proper name for the extinct predator with foot-long, serrated knife-like canines is Smilodon fatalis.

Up until the discovery of the fossil from Medicine Hat, Alberta, the species had never been found further north than Idaho. Or so it was thought...

A few years ago, a few small fossils caught the eye of researcher Ashley Reynolds as she was rummaging through the drawers at the Royal Ontario Museum in Toronto. The drawer was part of a treasure trove of 1,200 specimens collected in the 1960s by University of Toronto palaeontologist C.S. Churcher and his team. The specimens were collected over many field seasons along the bluffs of the South Saskatchewan River near Medicine Hat.

Churcher was a palaeontologist with a keen eye and a delightful man. I had the very great pleasure of listening to many of his talks out at UBC and at a few VanPS meetings in the mid-2000s. "Rufus" was a thoroughly charming storyteller and shared many of his adventures from the field. He moved out to the West Coast for his retirement but his keen love of the science kept him giving talks to enthralled listeners keen to hear about his survey of the Dakhleh Oasis in the Western Desert of Egypt, geomorphology, stratigraphy, recent biology, Pleistocene and Holocene lithic cultures, insights learned from Neolithic Islamic pottery to Roman settlements.

The specimens he had collected had been roughly sorted but never examined in detail. Reynolds, who was researching the growth patterns and life histories of extinct cats by looking at their bones, decided to look more carefully at the fossils Churcher had found, keen to add them to her research. And what a find she made!

One of the fossils labelled Smilodon was too small a piece to be identified. But another, a bone from the ancient cat's right front paw, was identical to other Smilodon bones and was positively identified as Canada's first Smilodon. CBC did a nice write up on her discoveries. 

References:
https://www.cbc.ca/n…/technology/sabre-toothed-cat-1.5305505

LATE HETTANGIAN TO EARLY SINEMURIAN FAUNA

Hiking the hills of Nevada looking for David Taylor's faunal succession based on ammonoids established for the Late Hettangian to Early Sinemurian interval in the Western Cordillera.

It was a tremendous experience to walk through time and compare the fossil assemblages here with our own in the Canadian Rockies.

Here the faunal sequence consists of one zone and four informal biochronologic units or assemblages and was outlined by Taylor as follows: Paracaloceras morganense assemblage, Badouxia oregonensis assemblage, Canadensis Zone, Metophioceras trigonatum assemblage and Coroniceras involutum. They matched up to specimens we collected over three field seasons to similar faunal outcrops of Late Hettangian to Early Sinemurian of the Last Creek and Tyaughton area of the Canadian Rockies.

The succession also correlates with the interval delineated by the Northwest European Angulata Zone through the Lyra Subzone. Two new genera (Guexiceras and Tipperoceras) are described along with 23 new species. The phylogenetic relationships of the earliest Jurassic ammonite superfamilies indicate that it is useful to include under the Psiloceratida, the Psilocerataceae and their derivatives including the Lytocerataceae. The Arietitaceae were derived from Hettangian lytocerataceans.

CAMBRIAN ARTHROPODS OF THE BALANG

A large extinct bivalved arthropod, Tuzoia sinesis (Pan, 1957) from Cambrian deposits of the Balang Formation. The Balang outcrops in beautiful Paiwu, northwestern Hunan Province in southern China. The site is intermediate in age between the Lower Cambrian Chengjiang fauna of Yunnan and the Lower to Middle Cambrian, Kaili Lagerstätten of Guizhou in southwestern China.

This specimen was collected earlier this week. It is one of many new and exciting arthropods to come from the site.

Balang has a low diversity of trilobites and many soft-bodied fossils similar in preservation to Canada's Burgess Shale. Some of the most interesting finds include the first discovery of anomalocaridid appendages (Appendage-F-type) from China along with the early arthropod Leanchoiliids with his atypical frontal appendages (and questionable phylogenetic placement) and the soft-shelled trilobite-like arthropod, Naraoiidae.

While the site is not as well-studied as the Chengjiang and Kaili Lagerstätten, it looks very promising. The exceptionally well-preserved fauna includes algae, sponges, chancelloriids, cnidarians, worms, molluscs, brachiopods, trilobites and a few non-mineralized arthropods. It is an exciting time for Cambrian paleontology. The Balang provides an intriguing new window into our ancient seas and the profound diversification of life that flourished there.

LATE SILURIAN EURYPTERID

The impressive homeotype specimen of Eurypterus lacustris from Late Silurian deposits in New York. UCMP Berkeley's paleontological collections.

About two dozen families of eurypterids “sea scorpions” are known from the fossil record. Although these ancient predators have a superficial similarity, including a defensive needle-like spike or telson at their tail end, they are not true scorpions. They are an extinct group of arthropods related to spiders, ticks, mites and other extant creepy crawlies.

Eurypterids hunted fish in the muddy bottoms of warm shallow seas some 460 to 248 million years ago before moving on to hunting grounds in fresh and brackish water during the latter part of their reign. Their numbers diminished greatly during the Permian-Triassic extinction, becoming extinct by 248 million years ago.

ESMERALDINA ROWEII

An Esmeraldina roweii multi-block of lovely trilobites from the Lower Lower Cambrian Poleta Formation of Esmeralda County, near Goldfield Nevada, plus a very interesting creature off to the lower left who looks to be an unidentified arthropod.

A very developed trilobite with long genal and axial spines, plus the ability to enroll. And all of this before the Olenellids existed. Collection of the deeply awesome George Walter Ast. Goldfield is located 247 miles southeast of Carson City, along U.S. Route 95.

MAMMUT AMERICANUM

The American Mastodon, Mammut americanum. Mastodons resemble elephants, but are more like elephant cousins.

A second species, Mammut pacificus, has recently been described from fossils found in Idaho and California. This specimen can be seen at the Smithsonian National Museum of Natural History. Photo credit: Guy Leahy.

MIDDLE TRIASSIC OF NEVADA

Searching for bedrock in outcrops of the West Humboldt Mountains, Nevada. Perhaps the most famous and important locality for the Middle Triassic (Anisian/Ladinian) of North America. These beautiful hills are home to Triassic ammonoid outcrops and plentiful ichthyosaur fossils.

J.P. Smith published on the marine fauna in the early 1900's. They formed the basis for his monograph on North American Middle Triassic marine invertebrate fauna published in 1914. N. J. Siberling from the US Geological Survey published on these outcrops in 1962. His work included nearly a dozen successive ammonite faunas, many of which were variants on previously described species.

Evidently, his collections consisted mainly of weathered material and were made without stratigraphic control because he believed that most, if not all, of these species were coexistent. The fossiliferous beds found here, as well as localities in north-western Nevada, were designated the 'Daonella dubia' zone. Dubious would be closer to the truth. Smith joined the 1905 Expedition of the University of California’s Department of Geology in Berkeley funded by the beautiful and bold, Annie Alexander, the women to whom the UCMP owes both its collection and existence.

MIDDLE TRIASSIC PAPER CLAMS & AMMONOIDS

Paper clams or "flat clams" were widespread in the Triassic. They often dominate the rocks in which they are found, as in these specimens from the Daonella dubia zone of the West Humboldt Range and the Desatoya Range of Nevada where they are associated with Ceratities trinodosus, Nevadites Whitney, Daonella lindstomi, D. moussoni and other species.

This designation was coined by J. P. Smith in the early 1900s for specific localities in the Humboldt Mountain Range.

Because of their widespread distribution and very high species turnover rates, they make for excellent biochronological macrofossils, helping us to correlate biological events through time.

We see the "cousins" of these Nevada specimens up in  Pine Pass near Chetwynd, British Columbia.

Pine Pass is part of the Pardonet Formation. Just a short hike from the road we were able to easily find the abundant outcroppings of the paper clam Monotis subcircularis, perfectly preserved and cemented in this strata from the Late Triassic.

GRASPING HOOKLETS AND CALAMARI

This well-preserved partial ichthyosaur was found in the Blue Lias shales by Lewis Winchester-Ellis in 2018. The vertebrae you see are from the tail section of this marine reptile.

The find includes stomach contents that tell us a little about how this particular fellow liked to dine.

As with most of his brethren, he enjoyed fish and cephalopods. Lewis found fishbone and squid tentacle hooklets in his belly. 

Oh yes, these ancient cephies had grasping hooklets on their tentacles. I'm picturing them wiggling all ominously. The hooklets were the only hard parts of the animal preserved in this case as the softer parts of this ancient calamari were fully or partially digested before this ichthyosaur met his end.

Ichthyosaurus was an extinct marine reptile first described from fossil fragments found in 1699 in Wales. Shortly thereafter, fossil vertebrae were published in 1708 from the Lower Jurassic and the first member of the order Ichthyosauria to be discovered.

To give that a bit of historical significance, this was the age of James Stuart, Jacobite hopeful to the British throne. While scientific journals of the day were publishing the first vertebrae ichthyosaur finds, he was avoiding the French fleet in the Firth of Forth off Scotland. This wasn’t Bonnie Prince Charlie, this was his Dad. Yes, that far back.

The first complete skeleton was discovered in the early 19th century by Mary Anning & her brother Joseph along the Dorset Jurassic Coast. Joseph had mistakenly, but quite reasonably, taken the find for an ancient crocodile. Mary excavated the specimen a year later and it was this and others that she found that would supply the research base others would soon publish on.

Mary's find was described by a British surgeon, Sir Everard Home, an elected Fellow of the Royal Society, in 1814. The specimen is now on display at the Natural History Museum in London bearing the name Temnodontosaurus platyodon, or “cutting-tooth lizard.”

In 1821, William Conybeare and Henry De La Beche, a friend of Mary's, published a paper describing three new species of unknown marine reptiles based on Anning's finds.

The Rev. William Buckland would go on to describe two small ichthyosaurs from the Lias of Lyme Regis, Ichthyosaurus communis and Ichthyosaurus intermedius, in 1837.

Remarkable, you'll recall that he was a theologian, geologist, palaeontologist AND Dean of Westminster. It was Buckland who published the first full account of a dinosaur in 1824, coining the name, "Megalosaurus."

The Age of Dinosaurs and Era of the Mighty Marine Reptile had begun.

Ichthyosaurs have been collected in the Blue Lias near Lyme Regis and the Black Ven Marls. More recently, specimens have been collected from the higher succession near Seatown. Paddy Howe, Lyme Regis Museum geologist, found a rather nice Ichthyosaurus breviceps skull a few years back. A landslip in 2008 unveiled some ribs poking out of the Church cliffs and a bit of digging revealed the ninth fossil skull ever found of a breviceps, with teeth and paddles to boot.

Specimens have since been found in Europe in Belgium, England, Germany, Switzerland and in Indonesia. Many tremendously well-preserved specimens come from the limestone quarries in Holzmaden, southern Germany.

Ichthyosaurs ranged from quite small, just a foot or two, to well over twenty-six metres in length and resembled both modern fish and dolphins.

Dean Lomax and Sven Sachs, both active (and delightful) vertebrate palaeontologists, have described a colossal beast, Shonisaurus sikanniensis from the Upper Triassic (Norian) Pardonet Formation of northeastern British Columbia, Canada, measuring 3-3.5 meters in length. The specimen is now on display in the Royal Tyrrell Museum of Palaeontology in Alberta, Canada. It was this discovery that tipped the balance in the vote, making it British Columbia's Official Fossil. Ichthyosaurs have been found at other sites in British Columbia, on Vancouver Island and Haida Gwaii, but Shoni tipped the ballot.

The first specimens of Shonisaurus were found in the 1990s by Peter Langham at Doniford Bay on the Somerset coast of England.

Dr. Betsy Nicholls, Rolex Laureate Vertebrate Palaeontologist from the Royal Tyrrell Museum, excavated the type specimen of Shonisaurus sikanniensis over three field sessions in one of the most ambitious fossil excavations ever ventured. Her efforts from 1999 through 2001, both in the field and lobbying back at home, paid off. Betsy published on this new species in 2004, the culmination of her life’s work and her last paper as we lost her to cancer in autumn of that year.

Charmingly, Betsy had a mail correspondence with Roy Chapman Andrews, former director of the American Museum of Natural History, going back to the late 1950s as she explored her potential career in palaeontology. Do you recall the AMNH’s sexy paleo photos of expeditions to the Gobi Desert in southern Mongolia in China in the early 20th century? You’d remember if you’d seen them. Roy Chapman Andrews was the lead on that trip. His photos are what fueled the flames of my own interest in paleo.

We've found at least 37 specimens of Shonisaurus in Triassic outcrops of the Luning Formation in the Shoshone Mountains in northwestern Nye County of Nevada, USA. The finds go back to the 1920s. The specimens that may it to publication were collected by Margaret Wheat of Fallon and Dr. C. L. Camp, UCMP, in the 1950s.  The aptly named Shonisaurus popularis became the Nevada State Fossil in 1977. Our Shoni got around. Isolated remains have been found in a section of sandstone in Belluno, in the Eastern Dolomites, Veneto region of northeastern Italy. The specimens were published by Vecchia et al. in 2002.

For a time, Shonisaurus was the largest ichthyosaurus known.

Move over, Shoni, as a new marine reptile find competes with the Green Anaconda (Eunectes murinus) and the Blue Whale (Balaenoptera musculus) for size at a whopping twenty-six (26) metres.

The find is the prize of fossil collector turned co-author, Paul de la Salle, who (you guessed it) found it in the lower part of the intertidal area that outcrops strata from the latest Triassic Westbury Mudstone Formation of Lilstock on the Somerset coast. He contacted Dean Lomax and Judy Massare who became co-authors on the paper.

The find and conclusions from their paper put "dinosaur" bones from the historic Westbury Mudstone Formation of Aust Cliff, Gloucestershire, UK site into full reinterpretation.

And remember that ichthyosaur the good Reverend Buckland described back in 1837, the Ichthyosaurus communis? Dean Lomax was the first to describe a wee baby. A wee baby ichthyosaur! Awe. I know, right? He and paleontologist Nigel Larkin published this adorable first in the journal of Historical Biology in 2017.

They had teamed up previously on another first back in 2014 when they completed the reconstruction of an entire large marine reptile skull and mandible in 3-D, then graciously making it available to fellow researchers and the public. The skull and braincase in question were from an Early Jurassic, and relatively rare, Protoichthyosaurus prostaxalis. 

The specimen had been unearthed in Warwickshire back in the 1950's. Unlike most ichthyosaur finds of this age, it was not compressed and allowed the team to look at a 3-D specimen through the lens of computerized tomography (CT) scanning. Another superb 3-D ichthyosaur skull was found near Lyme Regis by fossil hunter-turned-entrepreneur-local David Sole and prepped by the late David Costain. I'm rather hoping it went into a museum collection as it would be wonderful to see the specimen studied, imaged, scanned and 3-D printed for all to share. Here's hoping.

Lomax and Sven Sachs also published on an embryo from one of the largest ichthyosaurs known, a new species named Ichthyosaurus somersetensis. Their paper in the ACTA Palaeontologica Polonica from 2017, describes the third embryo known for Ichthyosaurus and the first to be positively identified to species level. The specimen was collected from the Lower Jurassic strata (lower Hettangian, Blue Lias Formation) of Doniford Bay, Somerset, UK and is housed in the collection of the Niedersächsisches Landesmuseum (Lower Saxony State Museum) in Hannover, Germany.

We've learned a lot about them in the time we've been studying them. We now have thousands of specimens, some whole, some as bits and pieces. Many specimens that have been collected are only just now being studied and the tools we are using to study them are getting better and better.

While they resembled fish and dolphins, Ichthyosaurs were large marine reptiles belonging to the order known as Ichthyosauria or Ichthyopterygia. In 2018, Benjamin Kear and his team were able to study ichthyosaur remains at the molecular level, Their findings suggest ichthyosaurs had skin and blubber quite similar to our modern dolphins.

While ichthyosaurs evolved from land-dwelling, lung-breathing reptiles, they returned to our ancient seas and evolved into the fish-shaped creatures we find in the fossil record today.

Their limbs fully transformed into flippers, sometimes containing a very large number of digits and phalanges. Their flippers tell us they were entirely aquatic as they were not well-designed for use on land. And it was their flippers that first gave us the clue that they gave birth to live young; a find later confirmed by fossil embryo and wee baby ichy finds.

They thrived during much of the Mesozoic era; based on fossil evidence, they first appeared around 250 million years ago (Ma) and at least one species survived until about 90 million years ago into the Late Cretaceous.

During the early Triassic period, ichthyosaurs evolved from a group of unidentified land reptiles that returned to the sea. They were particularly abundant in the later Triassic and early Jurassic periods before being replaced as a premier aquatic predator by another marine reptilian group, the Plesiosauria, in the later Jurassic and Cretaceous periods.

In the Late Cretaceous, ichthyosaurs were hard hit by the Cenomanian-Turonian anoxic event. As the deepest benthos layers of the seas became anoxic, poisoned by hydrogen sulphide, deep water marine life died off. This caused a cascade that wreaked havoc all the way up the food chain. At the end of that chain were our mighty predaceous marine reptiles. Bounty turned to scarcity and a race for survival began. The ichthyosaurs lost that race as the last lineage became extinct. It may have been their conservative evolution as a genus when faced with a need for adaptation to the world in which they found themselves and/or being outcompeted by early mosasaurs.

There are promising discoveries coming out of strata from the Cretaceous epeiric seas of Texas, USA from Nathan E. Van Vranken. His published paper from 2017, "An overview of ichthyosaurian remains from the Cretaceous of Texas, USA," looks at ichthyosaurian taxa from the mid-Cretaceous (Albian–Cenomanian) time interval in North America with an eye to ichthyosaurian distribution and demise.

The find and photos are all credited to Lewis Winchester-Ellis. Thank you for sharing your tremendous specimen with us. Lewis did much of the preparation of the specimen, removing the majority of the matrix. The spectacular final prep is credited to Lizzie Hingley, Stonebarrow Fossils, Oxfordshire. Her skill with an air scribe is unparalleled.

Link to Lomax Paper: https://journals.plos.org/plosone/article…

Link to Nathan's Paper: https://www.tandfonline.com/…/10.1080/03115518.2018.1523462…

Nicholls Paper: E. L. Nicholls and M. Manabe. 2004. Giant ichthyosaurs of the Triassic - a new species of Shonisaurus from the Pardonet Formation (Norian: Late Triassic) of British Columbia. Journal of Vertebrate Paleontology 24(4):838-849 [M. Carrano/H. Street]

ANAHOPLITES PLANUS

A beautiful specimen of the ammonite, Anahoplites planus (Mantell, 1822) from Albian deposits in Courcelles-sur-Voire, Aube, north-central France. Anahoplites (Sowerby, 1815) is a genus of compressed hoplitid ammonites with flat sides, narrow, flat or grooved venters, and flexious ribs or striae arising from weak umbilical tubercles that end in fine dense ventrolateral nodes.

Anahoplites is now included in the subfamily Anahoplitinae and separated from the Hoplitinae where it was placed in the older in the 1957 edition of the Treatise on Invertebrate Paleontology, Part L (Ammonoidea). Genera of the Hoplitinae tend to be more robust, with broader whorls and stronger ribs.

Anahoplites is found in Cretaceous (Middle to the late Albian) deposits from England, through Europe, all the way to the Transcaspian Oblast region in Russia to the east of the Caspian Sea. The Aube department, named after the local river, is the type locality of the Albian stage (d'ORBIGNY, 1842). Two formations are recognized in the clay facies (the "Gault" auct.) of the stratotype, the Argiles tégulines de Courcelles (82 m), overlain by the Marnes de Brienne (43 m). The boundary between the two formations is well-defined at the top of an indurated bed and readily identifiable in the field.

This involute (113 mm) specimen shows evidence of cohabitation by some of his marine peers. We see two different bryozoa, an oyster and some serpulids making a living and leaving trace fossils on his flat sides. This specimen was prepared with potase by José Juárez Ruiz of Spain.

PUNTLEDGE ELASMOSAUR

This toothy beauty is an elasmosaur, a large marine reptile now housed in the Courtenay and District Museum on Vancouver Island. This specimen was found by Mike Trask and his daughter in the winter of 1988 in the shale along the Puntledge River. It was the first elasmosaur found west of the Canadian Rockies and one of those moments that lights up and inspires a whole community.

The Puntledge Elasmosaur discovery led to the expansion of the local museum, the excavation site became a provincial heritage site and many, many teaching programs and guided tours have transpired since.

This is a far cry from other similar finds. You may remember an earlier find by Edward Drinker Cope. His 1868 discovery from outcrops in Kansas was originally described with the head incorrectly attached to the tail. It wasn't long before his archrival, one Othniel Charles March pointed it out quite publically. These were less gentle times and those two gents had a rivalry so underhanded and so public it is famously called, "the Bone Wars." The Courtenay and District Museum, the community surrounding it and allied organizations like the Vancouver Island Palaeontological Society, have a lot to be proud of. Their outreach and educational programs have inspired young and old alike.

ICHTHYOSAUR QUARRIES OF THE HUMBOLDT

Looking out over the Middle Triassic exposures of the Humboldt Mountain Range.

These hills were the site of the 1905 Expedition of the University of California’s Department of Geology in Berkeley funded by the beautiful and bold, Annie Alexander, the women to whom the UCMP owes both its collection and existence. Annie brought together a paleontological crew to explore these localities and kept an expedition journal of their trip which is now on display at the University of California Museum of Paleontology at Berkeley.

Annie's interest was the ichthyosaurs and she was well pleased with the results. They dodged rattlesnakes and tarantulas, finding many new specimens as they opened up new quarries in the hills of the Humboldt Range of Nevada.

Ichthyosaurs range from quite small, just a foot or two, to well over twenty-six metres in length and resembled both modern fish and dolphins. The specimens from Nevada are especially large and well-preserved. They hail from a time, some 217 million years ago, when Nevada, and parts of the western USA, was covered by an ancient ocean that would one day become our Pacific Ocean. Many ichthyosaur specimens have come out of Nevada. So many, in fact, that they named it their State Fossil back in 1977.

Fossil fragments and complete specimens of these marine reptiles have been collected in the Blue Lias near Lyme Regis and the Black Ven Marls. More recently, specimens have been collected from the higher succession near Seatown. Paddy Howe, Lyme Regis Museum geologist, found a rather nice Ichthyosaurus breviceps skull a few years back. A landslip in 2008 unveiled some ribs poking out of the Church cliffs and a bit of digging revealed the ninth fossil skull ever found of a breviceps, with teeth and paddles to boot.

Specimens have since been found in Europe in Belgium, England, Germany, Switzerland and in Indonesia. Many tremendously well-preserved specimens come from the limestone quarries in Holzmaden, southern Germany.

KASKAPAU FORMATION: DINOSAUR BONE

Dinosaur bone / Kaskapau Formation

Bones from a variety of dinosaurs have been found in the Tumbler Ridge area of British Columbia.

Here plaster is used to protect a valuable dinosaur bone collected from Flatbed Creek near Tumbler Ridge. The bone is from the Kaskapau Formation (Turonian) and was found a few metres away from a Tetrapodosaurus, "four-footed lizard," trackway.

Both Rich McCrea and Lisa Buckley have published extensively on the fossil material from this area. Additional Papers: Arbour et al. (2008ish) wrote up a paper in the Canadian Journal of Earth Science on dinosaur material collected in the 60s from BC; Rylaarsdam et al. contributed to the same journal two years earlier on the association of dinosaur footprints and skeletal material in the Kaskapau Formation.

MIDDLE TRIASSIC AMMONOIDS OF NEVADA

A beautiful block of marine fossils found in bedrock outcrops of the West Humboldt Mountains, Nevada. Perhaps the most famous and important locality for the Middle Triassic (Anisian/Ladinian) of North America. These beautiful hills are home to Triassic ammonoid outcrops and plentiful ichthyosaur fossils.

J.P. Smith published on the marine fauna in the early 1900s. They formed the basis for his monograph on North American Middle Triassic marine invertebrate fauna published in 1914. N. J. Siberling from the US Geological Survey published on these outcrops in 1962. His work included nearly a dozen successive ammonite faunas, many of which were variants on previously described species.

Smith was a surface collector and it showed in his research. His collections consisted mainly of weathered material and were made without stratigraphic control because he believed that most, if not all, of these species, were coexistent.

The fossiliferous beds found here, as well as localities in north-western Nevada, were designated the 'Daonella dubia' zone. Dubious would be closer to the truth. Smith joined the 1905 Expedition of the University of California’s Department of Geology in Berkeley funded by the beautiful and bold, Annie Alexander, the women to whom the UCMP owes both its collection and existence.

MUMMIFIED RED TILE FISH

An amazing mummified Red tilefish, Branchiostegus japonicus (Houttuyn, 1782) from Holocene deposits near Shizuoka, Japan. This specimen shows remarkable detail right down to the scales. Quite spectacular, truly.

Modern cousins of this 'horsehead' fishy fellow are native to the western Pacific ocean live as far south as the Arafura Sea today. They can grow to around 46 centimetres in length though most reach about 35 cm. Tilefish enjoy sandy and mud substrates and live in depths of 30 to 200 metres. Collection and photos from the deeply awesome Takashi Ito.

ANCIENT AEGEAN ELEPHANTS

The islands of the Aegean are peaks of underwater mountains that extend out from the mainland. 

Crete is the last of this range and boasts a diverse beauty from its high mountains of Psiloritis, Lefka Ori, and Dikti, to its ocean-caressed pink sand beaches.

Much of the island of Crete is Miocene and filled with fossil molluscs, bivalves, and gastropods who lived 5 to 23 million years ago in warm, tropical seas.

They are easily collected from their pink limestone matrix and are often eroded out, mixing with their modern relatives. Aside from the marine deposits, the island boasts some great vertebrate finds, including the remains of 

Deinotherium with its strange downward-curving tusks

Deinotherium giganteum, a massive 8 million-year-old mammal and primitive relative of the elephants roaming the Earth today. 

Deinotherium evolved from the slightly smaller, early Miocene, Prodeinotherium, though both genera were much larger than all of the more primitive proboscideans.

With an enormous large nasal opening at the centre of his skull, presumably, to house a rather largish trunk, Deinotherium may be the inspiration behind the myth of the Cyclops, the one-eyed giant from Homer's famous Odyssey. I'll share about some of the North African finds with you and you can judge for yourself. I think the resemblance is striking. 

The photo above is from the Grigore Antipa National Museum of Natural History in Bucharest, Romania. If you're in Romania, it's definitely a highlight. Photo credit: Flavius70 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=22541962. The illustration of Deinotherium ("terrible beast") is by the hugely talented Daniel Eskridge.

PERICLIMENES COLEMANI

These lovelies are Coleman shrimp, Periclimenes colemani. They are generally found in mating pairs atop the exquisitely beautiful but frightfully poisonous, Fire Sea Urchin, Asthenosoma varium.

The female of the Coleman pair in this photo is the slightly larger beauty on the left. She's looking poised and ready to catch something tasty with her open claws. Coleman shrimp and several other fish and invertebrates were named after the Australian naturalist and underwater nature photographer, Neville Coleman. It was his life's mission to document all of the sea life of Australia.

CERATIOCARIS OF SCOTLAND

This braw fellow is Ceratiocaris papilio (Salter in Murchison, 1859) a Pod Shrimp from the Silurian mudstones of the Kip Burn Formation in the Midland Valley of Scotland. 

He swam in our ancient seas, rising with the tide alongside and in the waters above many marine creatures that you will likely know — crinoids, brachiopods, trilobites and new and exotic fish — some sporting jaws for the first time in their lineage.

Ceratiocaris is a genus of extinct Palaeozoic phyllocarid crustacean whose fossils are found in marine strata from the Upper Ordovician through to the Silurian.

They are typified by eight short thoracic segments, seven longer abdominal somites and an elongated pretelson somite. Their carapace is slightly oval-shaped; they have many ridges parallel to the ventral margin and possess a horn at the anterior end.

This tidy specimen is from the Silurian mudstones that characterize the Kip Burn Formation with its dark laminated silty bands. The lower part of the Kip Burn houses the highly fossiliferous ‘Ceratiocaris beds’, that yield the arthropods Ceratiocaris, Dictyocaris, Pterygotus, Slimonia and the fish Birkenia and Thelodus.

The upper part of the formation, the Pterygotus beds, contain abundant eurypterid fauna together with the brachiopods Lingula and Ceratiocaris. The faunas in the Kip Burn Formation reflect the start of the transition from marine to quasi- or non-marine conditions in the group. Ceratiocaris is also well-known from the Silurian Eramosa Formation of Ontario, Canada, which also has rather nice eurypterids, too. Photo credit/collection of York Yuxi Wang and Tianyi Zhang.

Joseph H. Collette; David M. Rudkin (2010). Phyllocarid crustaceans from the Silurian Eramosa Lagerstätte (Ontario, Canada): taxonomy and functional morphology. Journal of Paleontology. 84 (1): 118–127. doi:10.1666/08-174.1.

M. Copeland; T. E. Bolton (1985). Fossils of Ontario part 3: the eurypterids and phyllocarids. Volume 48 of Life Sciences Miscellaneous Publications. Royal Ontario Museum. ISBN 0-88854-314-X.