Information about our FossilsInformatie over FossielenFossielien Information


© Henskens Fossils & John v. Straaten


The mammoth 

    After the dinosaurs became extinct approximately 65 millionyears ago, the birds and especially the mammals fill up the empty spaces andstart an impressive march. The ancestors of the mammoths emerged around 40million years ago in Africa. These are thefirst proboscideans. The trunk resulted from the growing together of the noseand the upper lip. Elephants grew larger but the neck stayed short, so a trunkwas needed to bring food and water to the mouth. The nostril is formed by a bighole at the point of attachment, so that the skull of elephants can easily berecognized.The first elephants evolved into more than 150 different species inthe course of time, some of them with very long tusks (these are actuallyextremely elongated incisive teeth). The bloom of the elephants was in theMiocene. About 20 million years ago the proboscideans could also move intoEurope and Asia when the African continental crust came so close to Europe that a land bridge must have been formed. About four orfive million years ago in Africa the elephantsdivided into three lines. From the first one, the Loxodonta, the Africanelephant emerged. The Indian elephant evolved from the second one, Elephas. Thethird one, Mammuthus, gave rise to the mammoths. So, as is sometimes thought,the mammoths are not the ancestors of the modern elephants. 

            Theproboscideans (mammoths also) are classified into species mainly bycharacteristics of the teeth (e.g. the number of enamel plates). With mostmammals, a new tooth grows vertically. With elephants, however, it growshorizontally. In total elephants will have 24 teeth during their life (six percorner). If the sixth and last tooth is worn away, the animal is condemned todie of starvation. If we assume that mammoths could get as old as modernelephants, their maximum age was about 60 years. 
            The ancestor of allmammoths is the African mammoth (Mammuthusafricanavus), which originated in theMiddle-Pliocene and died out about about three to four million years ago. Aboutthree million years ago the first mammoths appeared in Europe.They belonged to the species Mammuthusmeridionalis, also called southern mammoth. M. meridionalis was bigger thanthe modern elephants – 4 m high, and a weight of 10,000 kg - and without hair(the climate was warm then). But it had curved tusks, which is a characteristicof mammoths. It also spread east to Asia, and crossed the Bering Land Bridge toreach North America about 1.7 million yearsago when the climate was cold. When the temperature and thus the sea level roseagain, the two continents were separated. In North America,the isolated M. meridionalis evolved into the imperial mammoth (Mammuthus imperator), and it in turninto the Columbian mammoth (Mammuthus columbi). 
            One million years agothe climate changed. The temperature became colder, and this changed thelandscape in Europe. Woods changed into opengrasslands. M. meridionalis died out, but not before a small population adaptedto the changing conditions and evolved into Mammuthustrogontherii (steppe mammoth). Its molars were higher and had more ridges,so that they were more suitable for eating tough grasses. 
            Approximately 300,000years ago in Europe, the woolly mammoth, Mammuthus primigenius, emerged from M. trogontherii. It was even betteradapted to the cold. It was about as big as the Indian elephant - 3.2 m high -with a thick, long-haired woolly skin, a hypodermic fat layer, a short tail andsmall ears. Its molars were further adapted to eating the tough grasses fromthe tundra-steppes: they were higher and the number of enamel plates (up to 27)increased. It weighed 4,000 – 6,000 kg. 
M. primigenius is the lastspecies of the Mammuthus family. If people say ‘mammoth’, they usually refer tothe woolly mammoth. About 20,000 to 30,000 years ago the woolly mammoth wasalso able to reach North America through theBering Land Bridge. But its range was limited to Alaskaand Canada, while M. columbipreferred a milder climate and had moved south to the US and Mexico. Besides North America,woolly mammoths also reached Asia
            Woolly mammoths arewell-known because of their finds in the Siberian permafrost (constantly frozensoil). The animals are often so well-preserved that even skin, flesh and hairremain. In Europe, fishing boats often find remains in their nets, especiallyon the North Sea between Holland and England.In the Pleistocene era during the ice ages, the sea level was so low thatanimals (and humans) could live on the bottom of what is now the sea.
            At the end of thePleistocene, 10,000 years ago, a lot of big mammals like the cave bear, cavelion, giant deer, steppe wisent, but also the mammoth, died out. On the onehand this was caused by the changing climate (it became warmer, so that thevegetation changed), on the other hand because of the influence of humans,which rose in number and developed more efficient hunting techniques.
            Only a few mammothpopulations could survive on a number of islands that were still attached tothe main land during the last ice age. When the sea level rose they could notreturn, and because of the limited food supply on the islands they evolved intodwarf forms. Remains of these so-called pygmy mammoths have been found onWrangel island, which lies about 200 km north of Siberia.Remains of adult members of the woolly mammoth have been found that are about12,000 years old, but most remains are from dwarf forms only 1.8 m high andwhich only died out a few thousand years ago.

Straight-tusked elephant

The straight-tusked elephant (Elephas antiquus) lived in Eurasia during the Pleistocene. During the ice ages heremained in the south, and in warmer periods also moved north. It belongs tothe Elephas species, to which the modern Indian elephant also belongs.It was a little bigger than the woolly mammoth, with almost straight tusks. Themolars of the straight-tusked elephant had less enamel plates than those of thewoolly mammoth, because its food was softer and the molars thus wore lessquickly (the woolly mammoth mainly ate tough grasses). It became extinctapproximately 100,000 years ago, when another cold period started. Also known as Bush-elephant.

Cave bear

    Cave bears were mainly herbivores.Just like most modern bears, they probably ate dead animals now and then, butonly rarely will have killed prey themselves. They hibernated, for which theyusually used a cave (hence their name). Some animals died during their wintersleep (because of their old age, or because they had not built enough fatreserves in the autumn), and in some European caves (for example in Austria)the remains of more than a hundred bears have been found. This indicates thatsuch caves have been used by many generations of bears, sometimes over a periodof thousands of years. The cave bear (Ursus spelaeus) was about a thirdbigger than the modern brown bear. It became extinct 50,000 – 60,000 years ago,when the climate was so cold that the forests were replaced by steppes, whichdid not offer enough plants and fruits.


    The ancestors ofthe woolly rhino (Coelodonta antiquitatis) came from Asia.In the Lower Pleistocene, they moved to Siberia.There they became adapted to a cold climate, after which they moved on to Europe. It had a flat horn that enabled it to push aside snow inorder to graze. The horns of arhino are usually not preserved because they are not made of bone, but consistof thickly compressed hairs that decay after a while. After the last ice age,about 10,000 years ago, they died out, together with a lot of other animalslike the woolly mammoth that were adjusted to a cold climate.

Giant deer /Irish elk    

    Officially called Megaloceros giganteus, the giant deer is an extinct deerthat lived in Eurasia, from Irelandto China,during the Pliocene and Pleistocene epochs. It is famous for its formidablesize (about 2 m at the shoulders), and in particular for having the largestantlers of any known cervid (a maximum of 4 m from tip to tip). Its name is abit misleading: although large numbers of skeletons have been found in Irishbogs, the animal was not exclusively Irish, and neither was it closely relatedto either of the living species currently called “elk”. Many of the fossils found in Irish peatbogs are of males suffering from malnutrition after the rutting (mating)season, suggesting that they lived very like modern red deer today where males fight for theright to mate with a group of females every autumn.

Steppe wisent

    The steppe wisent (Bison priscus) was a bison found on steppes inEurope, Central Asia, Beringia and North Americaduring the Quaternary. They probably evolved in South Asia,around the same time as the aurochs, so they probably had the same ancestors.The steppe wisent became extinct in the late Pleistocene. It was replaced inEurope by the wisent and in Americaby the bison. Steppe wisents were over 2 m high and probably resembled thebison. The tips of the horns were sometimes more than 1 m apart, even the horns themselves measured over 0.5 m long.

Aurochs (Bos primigenius)

    The aurochs evolved in Asiaabout 2 million years ago and reached Europe, Middle East and Africaapproximately 250,000 years ago. It measured about 2 m at the shoulder,weighing 1,000 kg. The tip of the horns could be as much as 150 cm apart. Thehorn tips themselves are turned forward, as apposed to those of the steppewisent, which are turned upwards. The last recorded live aurochs, a female,died in 1627 in the Jaktorow Forest in Poland. Part of the aurochs liveson in recent European cattle. Domestication began in the Caucasus andMesopotamia about 8000 years ago, while genetic evidence suggests that theywere independently domesticated in northern Africa and India. Smaller forms of the aurochswere brought to Europe about 6500 years ago.

Cave lion (Panthera leo spelaea)  

The lion evolved in Africabetween 1 million and 800,000 years ago. It appeared in Europe700,000 years ago with the subspecies P.leo fossilis. From this lion evolved the cave lion about 300,000 years ago.During the Upper Pleistocene it also spread to North and South America via the Bering Street and developed there into P. leo atrox, the American lion.
The cave lion is considered to be a subspecies of theextant lion (Panthera leo) and livedfrom about 300,000 to 10,000 years ago, during the Pleistocene era (althoughsome finds indicate it may have lived until as recently as 2000 years ago inthe Balkans). It ranged across Europe and Asia, from England all the way to Siberia.Itis known from Paleolithic cave paintings, ivory carvings, and clay busts. Theserepresentations indicate that cave lions had protruding ears, tufted tails, andthat at least some males had a "ruff" or primitive mane around theirneck.
They probably preyed on the large, herbivorousanimals of their time. Their extinction may have been related to the Holoceneextinction event, which wiped out most of their prey. Cave paintings andremains found in the refuse piles of ancient camp sites indicate that they werehunted by early humans, which may also have contributed to their extinction.
The cave lion is one of the biggest cats that everlived. It was about 25 % bigger than the modern African lion, and averaged 3.5m in length, with a typical male weighing between 335 and 400 kg, and a typicalfemale weighing 175 kg. The Siberian tiger and the South American Smilodon(which was the largest of the saber-toothed cats) are both smaller. Only. P. leo fossilis and P. leo atrox were a little bigger than the cave lion.
Untilthe late Pleistocene the lion was the most widespread large land mammal besidehumans. They were found in most of Africa, much of Eurasia from western Europeto India and, in the Americas, from Alaskato Peru.They currently only exist in Africa (south of the Sahara) and northwest India.

Cave hyena (Crocuta crocuta spelaea)

Hyenas seem to have originated about 25 million years ago (mya) from an arboreal civet-like ancestor in Eurasia. Fifteen mya, dog-like hyenas flourished, with 30 different species being identified. Unlike some of their modern descendants, these hyenas were not specialized bone-crushers, but were more nimble, wolf-like animals. Five to seven mya, the hyenas were outcompeted by canids travelling from North America to Eurasia via the Bering land bridge. Some hyenas evolved bone-crushing teeth which allowed them to avoid competition with the canids. The peak diversity of the Hyenidae was during the Pleistocene, with 9 species of hyena. The bone-crushing hyenas became the dominant scavengers, taking advantage of the meat left over from the kills of big cats. The cave hyena is a subspecies of the extant spotted hyena (Crocuta crocuta) and lived in Eurasia during the late Pleistocene. Besides fossils it is known from prehistoric cave paintings. They used caves as dens, in which they accumulated the bones and horns of their food.

Hippo (Hippopotamus major)

The hippo is a large, mostly plant-eatingAfrican mammal, one of the only two extant species in the family Hippopotamidae(the other being the Pygmy Hippo from central Africa).It is theheaviest extant artiodactyl, inhabiting rivers and lakes in Africa south of theSahara. They are semi-aquatic, and emerge atdusk to graze on grass.
Despitetheir resemblance to terrestrial even-toed ungulates, their closest livingrelatives are cetaceans. The common ancestor of whales and hippos split from othereven-toed ungulates around 60 million years ago. The earliest known hippofossils date to around 16 mya, found in Africa.
During the Pleistocenehippos also ranged throughout North Africa and Europe.It can live in cold climates provided the water doesn’t freeze during winter.Hippos are good swimmers which allowed them to reach Crete, Cyprus, Malta andSicily, where dwarf species developed due to the reduced food supply and theabsence of predators.

Epileptobos groeneveldtii , Axislydekkeri and Rusa sp.

These fossils were found in Java, Indonesiaand are about 1.3 million years old. Epileptobos is a large extinctbovid, Axis is an extinct cervid (deer) and Rusa an extantcervid. The fossils were excavated in Trinil and Kedung Brubus. 
Trinil is very well known due to the excavationsof the famous Dutch geologist and anatomist Eugene Dubois (1858 – 1940). Trinilis the first hominid site that was described outside Europe.A skull cap and femur have been found by Dubois between 1891 and 1894. Heattributed them to the species Pithecanthropus erectus (“uprightwalking ape-man”). This name was changed later on to Homo erectus.Other Pleistocene mammals from this site include a species of the proboscidean Stegodon,the Java rhino, two monkey species, a large tiger species and a small leopardcat. The presence of these animals indicates an environment with both grassyplains and forests. 
The Kedung Brubus fauna includes a huge extinctpangolin, the proboscideans Stegodon and the fossil elephant Elephashysudrindicus, the large tiger species that is also known from Trinil, ahyena, otter, tapir, the Javan and Indian rhino and a hippo species. Thisimplies an open landscape with rivers.

Egg from anelephant bird (Aepyornis titan),Upper Pleistocene, Madagascar 

The Ratites, long-legged walking birds that can’t fly,appeared in the Upper Cre-taceous / LowerTertiary. On the different continents, different species evolved. Nowadays theyare represented by the emu and cassowary in Australiaand New Guinea, the kiwi of New Zealand, the nandoe in South America and theostrich in Africa. Two spectacular groupsbecame extinct only fairly recently – the elephant birds of Madagascar and the moas of New Zealand.
            Theelephant bird (Aepyornis titan) was the largest of the Aepyornis family.It could become three to four m high and weigh 400 kg, the heaviest birdthat ever lived (the giant moa of New Zealand, Dinornis maximuswas a little taller, but weighed less). The elephant bird laid huge eggs with avolume of seven litres and a weight of ten kg.
The name ‘elephant bird’ comes from an old Arablegend, which tells of a large bird, the ‘Rukh’, that grabbed elephants andlifted them in the air. The giant bird in the legendary book ‘Thousand and OneNights’ with Sinbad the Sailor was probably also an elephant bird. It becameextinct in the 17th century.

Description on Marsupials

A kangaroo is aherbivorous marsupial from the family Macropodidae (macropods, meaning ‘largefoot’). Besides the well-known larger species such as the red and greykangaroo, the family also includes many smaller species which include thewallabies, tree kangaroos, wallaroos, pademelons and the quokka, more than 60living species in all. The bigger species are endemic to Australia, while some smaller species can alsobe found in New Guinea.Like all marsupials, female kangaroos have a pouch in which the young (the‘joeys’) complete postnatal development.  
Kangaroos arose inthe early Miocene, but, being grazers, they prospered in the Pliocene andPleistocene, after Australia’stropical rainforests were replaced by grasslands in the late Miocene. Dozens ofextinct species are known, two genera (Ekaltadetaand Propleopus) were even carnivorousor at least omnivorous.  

Baringa nelsonensis  
This is a veryrare extinct species of wallaby known only from the NelsonBay site in western Victoria. It lived in the early Pleistocene.‘Baring’ is a Victorian Aboriginal word meaning ‘to cut’, an allusion to theunusual truncation by wear of the lower incisors. The species name reflects thetype locality. Baringa was named onthe basis of several fragmentary dentaries, maxillae and isolated teeth.  

The genus Macropus includes the (eastern and western)grey kangaroo, the red kangaroo, wallaroos and some wallabies. 
M. giganteus (the grey kangaroo) is an extant species. However,the grey kangaroos in the Pleistocene were much larger than their moderndescendants. 
M. titan is an extinct giant form of the grey kangaroo. It was flat-faced andabout twice as big as the modern grey kangaroo. Some scientists regard it as apre-dwarfing version of M. giganteus(as a sub-species, M. giganteus titan
M. siva is a rare Macropus species from eastern Australia. Some scientists considerit a sub-species of the extant agile wallaby (M. agilis).  

Protemnodon is a genus of macropods that existed in Australia and New Guinea in the Pleistocene.Based on fossil evidence it is thought that the known species were physicallysimilar to wallabies bur far larger. They are commonly called “giantwallabies”. 
P. anak was one of the biggest Protemnodons, with a weight of at least 90kilos, while P. roechus was one ofthe smallest. 

Sthenurus is an extinct genus of the so-called short-faced kangaroo. Thesthenurines became numerous about 2 million years ago. Fourteen species are nowextinct, with a single related species (the banded hare-wallaby) surviving ontwo islands off the coast of Western Australia. The extinct sthenurines varied in sizefrom quite small animals the size of a wallaby to giants which stood 2.5 metreshigh and weighed up to 200 kilograms. All had a single long toe with ahoof-like claw on their hind foot, a short, thick tail and long arms. Mostcharacteristic of all, the sthenurines had short, broad faces with an expandednasal area that may have been used for amplifying sound. 
S. occidentalis was a leaf-eating kangaroo, about the size of amodern grey kangaroo. In order to grind tough leaves and shrubs it had powerfuljaws and striations (sharp vertical ridges) on its teeth. The name ‘Sthenurus’(Latin for strong-tailed) was derived from the first description of this groupby Sir Richard Owen in the 19th century. He noted that the bones wereundoubtedly kangaroo-like and suggestive of powerful hind limbs and strongtails.  
S. gilli was a rather small sthenurine, with a body weight of about 20 kg. 

Troposodon minor  
This genus livedin the Pliocene and Pleistocene. They were browsers (while most other kangaroosare grazers), some could reach a body weight of 100 kg. T. minor was its smallest member with a body weight ofapproximately 40 kg. 


Diprotodontids were adapted for life in a land offorests. They were browsers with simple premolars and ate soft vegetation.There were several species of diprotodons, which all lived in Australia. Theyevolved in the mid-Miocene. The smallest were about the size of a small sheep,the biggest (D. optatum) was the sizeof a rhino. Diprotodons, along with a wide range of other Australian megafauna,became extinct a few thousand years after humans arrived in Australia. Thismass extinction was probably a result of climate change (in the latePleistocene, the forests were replaced by deserts and grasslands), humanhunting and/or human land management. 

Kolopsis torus lived in the late Miocene and was about 1.5 m longwith a shoulder height of 80 cm. It was one of the first diprotodontids andrelatively small. Later species were much larger.  

Palorchestes parvus was characterized by retracted nasal bones, a narrowelongated rostrum and enlarged infra-orbital foramina capable of carrying largebundles of nerves and blood vessels probably supplying a trunk. It was aboutthe size of a bull. 

Zygomaturus trilobus got its name from its wide flaringzygomatic arches. The Zygomaturus species were somewhat smaller than Diprotodon, and probably favoured the forested areasof south-eastern and south-western Australia, while Diprotodon was more suited to the open grasslands ofthe interior. The adult Zygomaturus was about 2.5 metres long and about 1 metre high at the shoulder, witha weight of 300-500 kilograms. 

Diprotodon optatum was the largest marsupial that ever lived. It was 3 mlong and 2 m tall at the shoulder, weighing about two tonnes. It existed from1.6 million years ago until about 40,000 years ago, through most of thePleistocene era. It inhabited open forests, wood- and grasslands, eatingleaves, shrubs and grasses. D. optatumwas first described in the 1830s by the famous British anatomist Sir RichardOwen. 

Thylacoleo carnifex 

T. carnifex is a member of the extinct thylacoleonid family,whose members evolved in the Oligocene and are informerly known as ‘marsupiallions’. T. carnifex was a leopard-sizedmarsupial very distantly related to wombats. It was first described by thedistinguished British palaeontologist Sir Richard Owen in 1858. It weighedabout 120 kg and was the largest mammalian predator in Australia. Astudy of carnivorous mammals of the world concluded that T. carnifex was the most specialised mammalian carnivore that hasever evolved, mainly because of its incredibly huge, sectorial meat-cuttingpremolar. It also had long sharp claws on its thumbs to grasp or slash prey.The limb proportions of Thylacoleoindicate that it could not run fast. This is probably related to the inabilityto run fast while carrying young in a pouch. Thylacoleo is thought to have been primarily an arboreal (treedwelling) animal. 


Sarcophilus is a genus of carnivorous marsupial best known forits only living member, the Tasmanian Devil (S. harrisii). Three species are known, S. laniarius and S.moornaensis are only known from Pleistocene fossils. D. harrisii can now only be found on Tasmania, on the Australian mainland itbecame extinct about 600 years ago (due to predation by human-introduceddingoes and hunting by indigenous Australians). The Tasmanian Devil is now thelargest carnivorous marsupial in the world (after the recent extinction of the Thylacine (‘Tasmanian Tiger’) in 1936.It is known to hunt both prey and scavenge carrion. It is a nocturnal animal.The fur is usually black, although irregular white patches on the chest andrump are common. Males are somewhat larger than females, with a head and bodylength of about 65 cm, a tail of 25 cm and an average weight of 8 kg. An analysis of mammalianbite force relative to the body size shows that the Tasmanian Devil has thestrongest bite of any living mammal.  


Perameles is a genus also calledlong-nosed bandicoots. A bandicoot is any of about 20 living species of smallto medium-sized, rat-like terrestrial marsupial omnivores of the familyPeramelidae. They feed on insects and plants and have a long, tapering snoutand elongated hind legs. 


Wombats are Australian herbivorous marsupials. They are short-legged,muscular quadrupeds, about one meter in length with a very short tail. They digextensive burrow systems with rodent-like front teeth and powerful claws. Theyare mainly nocturnal animals. Their fur color can vary from a sandy color tobrown, or from grey to black. There are three species, each around a meter inlength and weighing between 20 and 35 kg: the Common Wombat (Vombatusursinus), the Southern Hairy-nosed Wombat (Lasiorhinus latifrons)and the Northern Hairy-nosed Wombat (Lasiorhinus krefftii). 

Bettongia leseur 

Bettongia leseur, also known as theBoodie or Burrowing Bettong, is a small extant marsupial related to thekangaroo. It belongs to the family Potoroidae, which includes therat-kangaroos, potoroos and other bettongs. Fossils of this family appear inthe Mid-Miocene. B. leseur is asmall, rat-like marsupial with short, rounded ears and a lightly-haired, thicktail. It has a pointed rostrum and beady black eyes, hind limbs longer than theforelimbs and large hind feet. It is about the size of a wild rabbit, weighingabout 1.5 kg. 


Potorus is a small extant marsupial alsoknown as a Potoroo. Potoroosare the same size as rabbits. They have long feet and toes to hop and have greyfur. They come out at night to feed on seeds, fungi and insects. The potoroosweight is 1.5-2.5 kg. 

Megalania prisca 

Megalania was a giant varanid lizard also known as the Giant Goanna, that livedin the Pliocene and Pleistocene. It grew to lengths of at least 5 metres,perhaps 7. At about 600 kg, it was several times as heavy as the largest livinggoanna, the Komodo Dragon of Indonesia (Varanuskomodensis). It was probably an ambush killer and scavenger. Megalania is known only from fragmentarymaterial. It is the largest known land-dwelling lizard and belonged to thefamily that includes the goannas or monitor lizards. It appears to have becomeextinct around 40,000 years ago (although numerous people claim to have seenvery large lizards in Australiaand New Guineain the last 100 years, suggesting Megalaniais still alive). It was the largest predator in Australia during the last 2 millionyears. Megalania is now often put inthe genus Varanus, which includes allmonitor lizards.

Tiliqua scincoides  

Members of the genus Tiliqua arealso called blue-tongued skinks. It contains some of the largest members of theskink family. They are commonly called blue-tongued lizards in Australia,where true lizards do not naturally occur. T.scincoides is an extant species with a pale brown head with alternatingstreaks or blotches of dark brown and cream on its back. Its English name comes from its distinctiveblue tongue. When disturbed it gapes its mouth open, sticks out its blue tongueand puffs up its body, hissing loudly. This is an effective defence mechanism,deterring many intruders.  


Emydura is a genus of extant turtles,also called Australian short-necked turtles. The six species of the genus Emydura arewebbed-footed and semi-aquatic river turtles. They are characterized byunusually short necks. 

Pallimnarchus pollens 

Pallimnarchus is an extinct genus ofcrocodile from the Pliocene and Pleistocene of Australia. The genus consists ofonly one species, P. pollens. It wasabout as big as a modern saltwater crocodile. It had conical ziphodont(serrated and curved posteriorally) teeth and probably specialized in ambushingprey like kangaroos and diprotodons in shallow water.

THE TERTIARY ERA(Pliocene, Miocene, Oligocene, Eocene and Paleocene)  © Henskens Fossils & John v. Straaten


    Carcharodon was a whiteshark species that lived in the Miocene and Pliocene. It must have grown toabout 15-18 m in length. However, this is difficult to tell exactly, since ashark skeleton consists of cartilage that hardly fossilizes since it is verysoft. What we do find a lot from sharks are their teeth. Not only because theyare hard and have a big chance to be preserved, also because a shark constantlyreplaces them. A shark has several rows of teeth, and can produce up to 15,000teeth during its life. Carcharodon teeth can be 20 cm long. The height of itswide open jaws must have been about 1.5 m. Its main food source were probablywhales.


    The Cainotheriidae are small artiodactyls(even-toed hoofed plant-eating mammals) that suddenly appeared in the LowerOligocene of western Europe. Cainotherium looked like a hare. This isprobably because it lived the same life style, a good example of convergentevolution. It is not related to hares, but has evolved similar adaptations asit occupied similar niches. Cainotherium became extinct in the UpperMiocene and left no descendants.

Messelornis cristata

    Messelornis cristata is a fossil rail-likebird from the famous Messel Pit fossil site in Germany,near Darmstadt.This pit has yielded lots of superb Eocene fossils of animals that lived in orclose to a fresh-water lake. A lot of fossils even show the outlines of hairsand feathers. The Messel sitewas actively mined for its oil shales from 1859 to 1971 but now falls under theHeritage Protection Act. 
    Collecting fossils from the Messel site requires aspecial technique. Once is fossil is discovered (by splitting the thin shaleslabs) it needs to be kept wet. If the shale is allowed to dry out, then thefossil disintegrates. Then, still keeping the fossil damp, the shale iscarefully removed from around the bones. Then the bones are coated with resinto hold them in place. Now, the whole slab is turned over and the other side ofthe fossil exposed in the same way. Eventually, the fossil is completely freefrom the rock and encased in resin. 

    M. cristata  was about the size of a moorhen and earlier they were also classified inthis group, the rails. It now appears, however, that the Messelornithidae aremore related to the present crane family (Gruiformes). They had short wings,long legs and short toes. The tail feathers were long. On the head they had ahelmet-shaped crest. The full skeleton is 25 to 30 cm in size.

The fishes Atractosteus starusi, Amphipercamultiformis, Thaumaturus intermedius and Palaeoperca proximafrom the Fish page also come from this site.


    The Palaeobatrachidaeis an extinct group of frogs. They lived mainly from the Eocene throughPliocene in Europe, but some fossils are knownfrom the Cretaceous. They were purely aquatic amphibians, even their tadpoleshave been found as fossils. Some palaeobatrachids reached a size of 12 cmsnout-vent length.

Phareodustestis, Diplomystus dentatus, Knigthia eocaenea and Priscacara serata

    All these fishes come from the world-famous fossil locality of theGreen River Formation in Wyoming, US (namedfor the present-day Green River, a tributary of the Colorado River). It covers about 25,000 square miles of Wyoming,Colorado and Utah and is one of the largest lacustrinesedimentary formations in the world. The deposits are from 40 - 50 millionyears ago. The region at that time was sub-tropical to temperate. Some 60vertebrate taxa have been described, inlcuding crocodiles and birds. Theexcellent preservation of the Green Riverfossils is probably caused by the great depth of the lakes and the resultinganoxic conditions that would have kept scavengers away from the dead animals andplants. The limestone matrix is so fine-grained that fossils often showspectacular details, like the veins in insect wings and leaves.

Titanothere sp.

Titanotheriidae, also called Brontotheriidae, isa family of extinct mammals from the order Perrisodactyla, that includeshorses, rhinos, and tapirs. They looked like rhinos but are probably related tohorses. They lived in the Eocene and Oligocene. The term “Brontothere” means“thunder beast” in Sioux Indian language. Brontotheres have four toes on theirfront feet and three on their hind feet. Their teeth are adapted to cutting leaves.The history of this group is well known due to an excellent fossil record inthe U.S.The earliest brontotheres were rather small, no more than a meter in height,and were hornless. Later brontotheres evolved massive body sizes, up to 2.5 min height and had evolved bizarre hornlike appendages. The sexually dimorphicforked horns suggest that brontotheres were highly social and males probablycompeted for mates by clashing their heads. However, unlike rhinos, the hornswere composed of bone, and were placed side-to-side instead of front-to-back.Brontotheres probably became extinct when the great forests were replaced bygrasslands where horses, rhinos and other mammals became more abundant.

THECRETACEOUS ERA  © Henskens Fossils & John v. Straaten


    As its name suggests, Aegyptosauruswas discovered in Egypt.It lived in northern Africa during the mid andlate Cretaceous. It was a herbivore which was about 15 m long, with a long neckand tail. A lot of its fossils were found by German scientists in the 1930s.The fossils were stored in a Munichmuseum but were destroyed during a bomb raid in 1944. Aegyptosaurus was a closerelative of Argentinosaurus, a larger dinosaur found in South America. It may have evolved from Argentinosaurusafter it crossed the ancient land bridge between South America and Africa.

Crocodilus spenceri and Phosphatosaurus gavialoides

    Alligators, caimans, gavials, and crocodiles belong tothe family Crocodylidae. Although this family has existed since the upper Triassic,over 200 million years ago, reptiles which can definitely be classed as modern Crocodylidaeonly appear in the fossil record about 80 million years ago. The groupCrocodylia consists of modern crocodiles, alligators, and gavials. Crocodilianshave a long head with nostrils at the tip of the snout, four legs projectingsideways, heavy scales, a muscular tail, and partially webbed hind feet.Crocodilians are semi-aquatic; they spend much of their time in water, but mustlay their eggs on land. Their extinct relatives share many skeletal featureswith modern crocodilians, but were quite different. Some were small (less than50 cm), lightly built, and probably preyed on insects and very small reptiles.Others even walked on two legs, or had hind limbs longer than their forelimbs,betraying their bipedal ancestry. The biggest croc that ever lived was Sarcosuchusimperator. It lived about 110 million years ago in what is now northern Africa. Based on measurements of the skulls and bones,and comparison to recent crocs, Sarcosuchus grew to lengths of 11-12 m.


    Elasmosaurus was a plesiosaur with an extremely long neck thatlived in the world sees in the late Cretaceous. Its name means “thin-platedlizard”. This is because it had platelike bones in its pelvic girdle. It is thelongest plesiosaur that ever lived (about 14 m in length). More than half ofits length was neck, which had more than 70 vertebrae, more than any otheranimal. It had a large body and four flippers for limbs, a small head withsharp teeth, and probably ate fish, belemnites and ammonites. It was describedin 1868 by Edward Drinker Cope from fossils found in Kansas, US. He accidentally placed the headat the tail end. Othniel Charles Marsh made him aware of the error, and thisevent is cited as the cause of their long-lasting rivaly knows as the BoneWars.


Mosasaurs were carnivorousmarine reptiles with flippers that likely descended from varanid lizards. Theyare named after the Dutch river Meuse where the fossils were first discovered. Thisriver runs next to the city of Maastricht, after which the period they lived in(Upper Cretaceous) was named (Maastrichtian). These fossils were from thespecies Mosasaurus hoffmanni. Mosasaurs dominated the shallow seasworldwide during the late Cretaceous. They were top predators that ate almostanything, even ammonites. Some fossil ammonites cary the bite marks ofmosasaurs.
Mosasaurus was the largest ofall mosasaur types known. It could reach a length of 18 m, with a skull ofalmost 2 m. The lower jaw is loosely hinged to the skull with a moveable jointon each side just behind the teeth. This loose joint must have permitted theanimal to swallow large prey, much as some living snakes do. Finds of mosasaurembryos inside the skeleton of adult specimens indicate that mosasaurs, justlike ichthyosaurs, were viviparous and gave birth to live young.

Tharrhias araripis

    These fishes come from the Santana Formation, innortheast Brazil,one of the richest fossil deposits in the world. About 110 million years agothis was a shallow inland sea. At that time Africa and South America had only just drifted apart, and were still located closeto each other. The geological formation, named after the village of Santanado Cariri, lies at the base of the Araripe Plateau. The strata were laid downduring the early Cretaceous, 114 to 90 million years ago, in a shallow inlandsea. At that time, the South Atlantic wasopening up in a long narrow shallow sea. The Santana Formation is well-knownfor the well-preserved fossil fishes. Even the contents of their stomachs arepreserved, permitting paleontologists to establish predator-prey relationshipsin this ecosystem. There are also fine examples of pterosaur reptiles andamphibians, invertebrates (particularly insects), plants and even dinosaurs.The fossils are often found as accretions that formed nodules around deadorganisms, preserving even soft parts of their anatomy.


Coelacanths evolved approximately 380 million years ago. Since no fossils of these fishes have been found in rocks from the Tertiary or younger, palaeontologists assumed they had died out at the end of the Cretaceous, 65 million years ago, together with the dinosaurs and other big reptiles. Until a Coelacanth was caught at a depth of 200 m off the coast of Madagascar in 1938. Closer investigation showed a population that consisted of several hundred specimens. In 1998, another Coelacanth population was found near Sulawesi, Indonesia. These modern Coelacanths grow to about 1.8 m in length. They are the last of the lobe-finned fishes. This class had four more subclasses in the Devonian, which are now all extinct. The bones of the pectoral and pelvic fins in lobe-finned fishes already clearly show a humerus, radius and ulna. Scientists used to think that the lung fishes were the direct ancestors of the amphibians, nowadays most palaeontologists think these were the lobe-finned fishes. In a group of lobe-finned fishes living in the Devonian, the swim-bladder evolved into lungs, when, for unknown reasons, they left the sea water.

Confuciusornis sanctus

    Just likeArchaeopteryx, Confuciusornis is proof that birds evolved from reptiles.Confuciusornis is about 25 million years younger than Archaeopteryxand is the oldest known bird to have a toothless beak. However, the wings stillhave three claws. It must have been a better flyer than Archaeopteryxbecause it had lighter bones (in modern birds the bones are completely hollowto save weight). The males were a little larger than the females and had twovery long, narrow tail feathers. Confuciusornis is found in depositsfrom the Lower Cretaceous of the Liaoningprovince in China.The first specimen was found in 1994. The fossils have almost all been found ina relatively small area, indicating they lived in large colonies close to water(the fossils are deposited in what was once the bottom of a large freshwaterlake).


    Turtles are an ancient group of reptiles. The earliestturtles were enormous, tortoise-like animals. Millions of years of evolutionresulted in some species adapting to life in the oceans. The earliest knownmarine turtle fossils are about 110-150 million years old. Allopleuronis known from Upper Cretaceous deposits of North America, northern Africa and Europe. Once the oceans of the world had an abundance ofturtle species, but the last hundred years have seen a steady decline of theturtle population. Marine turtles are now an endangered species. There are justseven extant species today.

THE JURASSIC ERA © Henskens Fossils & John v. Straaten


    Pterosaurs (‘flyingreptiles’) evolved approximately 230 million years ago. They developed in thesame period as the dinosaurs, at the end of the Triassic, and also had the sameancestors (the archosaurs, from which the crocodiles also evolved). The wing isformed by a greatly elongated fourth finger. From the top of this finger, aleathery skin stretched towards the thigh bone of the hind legs. The otherthree fingers formed a claw halfway the wing. The fifth finger was stillpresent in early species (although already greatly reduced), but was gone inlater forms. The wings could be folded backwards, so that pterosaurs were ableto walk on their hind legs on the ground, supported by their wing claw.

More than 120different species are known. The smallest had the size of a sparrow, thelargest (Quetzalcoatlus) had a wing span of about 12 m. Just as inbirds, pterosaur bones were hollow to save weight. It were the first vertebratesthat were able to fly. Most species lived from insects and fishes, which theycaught from the surface waters of the seas. Pterosaurs were probably active,warm-blooded animals. The ones with a large wing span must have been able toglide for a long time by using the thermal currents (upward movement of heatedair). Just like many other reptile families, they became extinct at the end ofthe Cretaceous.

Pterosaurs arenot the ancestors of birds. Birds developed in the Jurassic from small,carnivorous reptiles (probably dinosaurs), and pterosaurs and birds stillshared the skies for almost 100 million years.

    Rhamphorhynchus had a long tail. Its namemeans “beak snout”. It had a wingspan of 1 m and a long tail stiffenened withligaments which ended in a vane. It probably ate fish and it is believed thatone of the ways it hunted was by dragging its beak in the water, catching fish,and tossing them into its throat pouch, a structure similar to that ofpelicans, which has been preserved in some specimens. Although fossils havebeen found in England, thebest preserved come from the Solnhofen quarry in Germany. Many of these fossilspreserve not only the bones but skin impressions too. It lived in the UpperJurassic.

    Scaphognathus had a skull length close to 12 cm and awingspan of about 90 cm. It had a characteristically broad jaw, relativelyshort tail and short wings in comparison to other rhamphorhynchoids and a broadsternum. Compared to Rhamphorhynchus, the teeth pointed downward instead of forward.

Aroclesaltivelis, Allothrissops salmoneus, Allothrissops mesogaster, Tharsis dubius,Ascalabos voithii, Pachytrhissops, and Leptolepides sprattiformis

    All these fishes come fromthe world-famous fossil Lagerstätte of Solnhofen near Munichin southern Germany.In the Upper Jurassic, approximately 150 million years ago, a lagoon with adirect connection to the open sea covered this area. The deposits have formedlight-coloured rock layers that can easily be broken into plates. Already inthe Middle Ages these were used as roof and floor covering, but especially inthe 19th century they were used a lot in the lithographic industry.During this period, a lot of fossils were found. Due to the fine-grainedstructure of the rocks, they show even the smallest details. Also, almost allof the fossils are still intact, not being touched by scavengers. This probablymeans that life was not possible in the lagoon’s lower water levels. It musthave been very salty at the bottom, without any oxygen. More than 400 differentfossil animal species from the Solnhofen area have been determined. Not onlyfrom marine animals such as fishes, crustaceans, star fishes etc., but alsofrom animals that lived on land. These have been carried to the lagoon byrivers and mudflows (reptiles, insects, and even one dinosaur species, Compsognathus),or flew above the lagoon and fell down in the water (maybe during a storm) anddrowned (pterosaurs, and the most famous of all Solnhofen fossils, theprehistoric bird Archaeopteryx).

Mesolimulus walchi

    Horsehoe crabs are distant relatives of spidersand probably descended from the ancient eurypterids (sea scorpions). Theyevolved in the Cambrian with other primitive arthropods like the trilobites.Horseshoe crabs are one of the oldest classes of marine arthropods, and areoften referred to as "living fossils", as they have not changed muchin the last 350 to 400 million years. Limuluspolyphemusis one of the few surviving species of Limulus, and it closely resembles Mesolimuluswalchi. They are found in the Gulf ofMexico and along the northern Atlantic coast of North America.

Hyphalosaurus lingyuanensis

    Hyphalosaurus is an extinct genus from the order Choristodera, (semi-)aquatic diapsid reptiles which ranged from the Jurassic, or possibly late Triassic, to at least the early Miocene. They are found in the early Cretaceous Jehol group from the Yixian Formation in China. The slab and counterslab of the holotype were given to different groups of researchers, each giving it a diffent name, Sinohydrosaurus and Hyphalosaurus. It was quickly recognized that they represented the same animal, and since the name Hyphalosaurus appeared in a publication first, this is its official name. It achieved an adult body size of about 80 cm. It was aquatic, a lifestyle reflected by its elongate neck and tail and reduced limbs. In 2007 a specimen was found with two heads, marking the oldest case of polycephaly.

Pseudorhina minor

Pseudorhina is related to the recent squatinids, the so-calledangel sharks, bottom-dwelling sharks with a ray-like shape. They are an ancientlineage, first appearing in the fossil record about 150 million years agoduring the late Jurassic period. The remains of articulated angel sharks areknown from the marine deposits of Solnhofen, southern Germany.Specimens of more than one meter in length have been recorded. The oralaperture is located underneath and at the forward end of the head. Pectoral andventral fins are close to one another. 
The genus Pseudorhina is extinct but it has closerelationships with the genus Squatinawhich has 15 extant members.


Ichthyosaurs werereptiles of which the ancestors lived on land, but later decided to go back tosea (possibly under pressure of the dinosaurs, which dominated on land). Theirbody shape looks a lot like that of a dolphin (but with a vertical instead of ahorizontal tail, and four instead of two flippers). Just like dolphins (mammalswhich later also returned to sea), ichthyosaurs had lungs and had to come tothe surface now and then to breathe. More than 80 species are known, of whichthe biggest one (Shonisaurus) could reach 15 m in length. Skeletons ofichthyosaurs have been found containing the remains of unborn young. Thisproves they had an internal egg development and that the young were deliveredalive. They evolved in the Triassic (about 245 million years ago) and becameextinct in the Cretaceous (some 90 million years ago, long before the dinosaursand many other reptiles died out).

           They lived on fish, ammonites and belemnites. Ichthyosaurs have, in comparisonto the rest of their body, the biggest eyes of all animals. Species of thegenus Temnodontosaurus even had the biggest eyes ever, with a diameterof 26 cm(even bigger than those of a blue whale). Even the eyes are adapted to thestreamlined ichthyosaur body. Like most birds and other reptiles, ichthyosaurshave a bony eye ring, the so-called sclerotic ring. This ring, which encirclesthe lens, is flattened in ichthyosaurs, and the outer edge is bent inwards, sothat also the eye ball is flattened, and the extraordinary big eyes hardlystick out. 

Stenopterygiussp., Lower Jurassic, Holzmaden, Germany

 Stenopterygius is known from Europe (England,France, Germany, Luxembourgand Switzerland).Its maximum length was 4 m.Stenopterygius was physically similar to the better known Ichthyosaurus,but had a smaller skull and narrower flippers. Stenopterygius was a veryfast swimmer, with a cruising speed similar to that of tuna, which is among thefastest of all living fishes.

Since the skeleton is as good as complete, thisichthyosaur must have drifted at the surface only for a short while after itsdeath, before it started to sink. The deeper it sank, the more the chest andlungs were compressed. The body’s centre of gravity moved into the direction ofthe head. As a consequence, such ichthyosaurs often sank towards the sea bottomhead first, with a speed of ± 1.5 m/s. When it collided with the sea floor, thesnout broke into several pieces, and also the skull was damaged. Approximately 30 cm behind the skull, thespinal column is broken, and some vertebrae are dislocated. Several parts ofthe snout and left front flipper entered the left eye ball and are now lying ontop of the sclerotic ring. The flipper at the left front became detached fromthe shoulder joint and moved towards the skull. The fossilized stomach contentscan still be seen in the form of a brown spot.

This ichthyosaur is mentioned in a Germanscientific article about ichthyosaurs which sank to the sea bottom head first(Der Ichthyosaur vom Hauensteiner Nebelmeer, H. Hänggi, 2007, NaturforschendeGesellschaft des Kantons Solothurn).

THE TRIASSIC ERA © Henskens Fossils & John v. Straaten


    Keichousaurus is a marine reptile fromthe Triassic. The name derives from Kweichow (now Guizhouprovince) in Chinawhere the first fossil specimen was found in 1958. Keichousaurus was highly adapted to the aquatic environment. Theygrew to about 30 cm in length, and had both long necks and tails, withelongated, five-toed feet. The pointed head and sharp teeth indicate they atefish. They belonged to the sauropterygians (“lizard flippers”), a group of very successfulaquatic reptiles that are united by a radical adaptation of their shoulder,designed to support powerful flipper strokes.


    Nothosaurs were Triassic marinesauropterygian reptiles that had the same life style as seals today, catching food in the sea water but comingashore on rocks and beaches. They averaged about 3 m in length, with a longbody and tail. The feet had become paddle-like, and were most certainly webbedin life, to help power the animal when swimming. The neck was quite long, andthe head was elongate and flattened, and relatively small in relation to thebody. The margins of the long jaws were equipped with numerous sharpoutward-pointing teeth, indicating it ate fish. Nothosaursevolved from pachypleurosaurs and were the ancestors of the more completelymarine plesiosaurs, which replaced them at the end of the Triassic. They livedin Europe, North Africa and Asia.

THE PERMIAN ERA © Henskens Fossils & John v. Straaten


    Archegosaurus belongs to theLabyrinthodontia, a group of extinct amphibians. They were the first vertebratesto conquer land in the Devonian. The Labyrinthodontia  evolved from the Crossopterygii,a class of lobe-finned fishes, consisting of lungfish and coelacanths. In a group of lobe-finnedfishes living in the Devonian, the swim-bladder evolved into lungs, when, forunknown reasons, they left the sea water. Archegosaurus could reach alength of 1 m. Together with Sclerocephalus and Actinodon itbelonged to the biggest amphibians of Europeduring the Permian.


    Discosauriscus was an amphibium that lived in the early Permian.Lots of its fossils have been found in deposits of fresh water lakes in centraland western Europe, especially in the Czech Republic.Until now only fossils from juvenile specimens have been found, not fromadults. This is probably because adults used these lakes as spawning groundsand that animals, as soon as they reached maturity, moved to another habitat.Two species are known: D. austriacus and D. pulcherrimus. Thefirst one is much more common.


    Sclerocephaluswas a salamander that lived about 280 million years ago (in the Lower-Permian)of what is now south-western Germany.It lived in freshwater lakes and with its maximum length of 2 m it was one of Europe’s biggest amphibians ever. It fed on fish andother amphibians. Like all amphibians, the larvae had gills with which theyretrieved oxygen from the water. The adult animals had lungs and so were ableto also temporarily live on land.

Micromelerpeton credneri

Micromelerpeton was anamphibian that lived in the Permian in what is now southwestern Germany.They belong to the branchiosaurs: mature amphibians that show larval characterssuch as external gills and unossified elements in the wrist and ankle. Micromelerpeton could reach a length of20 cm. It lived 290 – 260 mya. During that time, Germany lay far more to the southand the regional temperature was tropical and humid, ideal for amphibians. Themain enemies of Micromelerpeton in thePermian lakes must have been the much larger amphibian Sclerocephalus (see above article) and freshwater sharks like Orthacanthus.

Orthacanthus senckenbergianus

Orthacanthus is a fresh water shark that livedin the Upper Carboniferous and Lower Permian of Europe and North America. With its long body and long dorsal fin it looked a bitlike a moray. It had a spine just behind its head and could reach a length of 3m. It was first described in 1889. The white color of the fossil is a result ofheating-up of the sedimentary rock by rising lava. It belonged to theXenacanths, the first sharks to enter fresh water. They lost their primitiveshark shape and evolved toward an eel-like form, with a long, slender body,tapered tail, and elongate dorsal fin.
Fossils ofcomplete sharks are rare as their skeleton is from cartilage which is muchsofter than bone.

THE CARBONIFEROUSERA © Henskens Fossils & John v. Straaten


Ferns are vascularplants that differ from the more primitive lycophytes in having true leaves,and from the more advanced seed plants in lacking seeds. Unlike the othervascular plants, the flowering plants and conifers, where the adult plant growsimmediately from the seed, ferns reproduce from spores. Ferns are (relatively)delicate plants that only grow in areas with moist conditions. They favoursheltered areas under the forest canopy, along creeks and streams and othersources of permanent moisture. 
Ferns first appearin the fossil record in the Lower Carboniferous, meaning they were alreadyaround for two hundred million years before the flowering plants evolved. Bythe Triassic, the first evidence of ferns related to several moden familiesappeared. The first modern families evolved in the Upper Cretaceous.

THE DEVONIAN ERA © Henskens Fossils & John v. Straaten

Rhinopteraspis dunensis        Coccosteus cuspidatus


Armored fishes

The first armored fishes developed in the Lower Ordovician. They belongto the class Agnathans, the first vertebrates, which were still jawless. Mostspecies lacked paired fins, and only possessed a tail fin. Many species alsodid not have a dorsal fin. For compensation, they had protrusions on the headshield that served as a stabilizer. They swam using only their tail. TheAgnathans also included non-armored fishes. This class became extinct at theend of the Devonian. A second class which includes armored fishes are thePlacoderms. As opposed to the Agnathans, they had jaws and paired fins. Theyalready die out in the Lower Carboniferous.All armored fishes had an amazingexoskeleton, consisting of a head shield, and, for the Placoderms, hard, bonyplates halfway the body. Their length varied from a few centimeters to 6 m (Dunkleosteus).Besides protection against predators, the armor also served to support thebody.
            Rhinopteraspisis an Agnathan.
Althoughlacking paired fins, the pteraspids were probably powerful swimmers. Stability was provided by the wing-like outgrowths from the back of the headshield.  A large spine over the back acted as a kind of dorsal fin whiletwo rigid 'wings' or keels functioned as pectoral hydrofoils.   Thelong, flexible tail was also hydrodynamic, with the lower lobe elongated toprovide lift at the front of the body during swimming. Additional lift wasprovided by the elongated snout, which was drawn out into a bladelike'rostrum', below which the mouth opened. The rostrum may have served a dualpurpose, both hydrodynamic and used to probe the mud and sediment for smallorganisms.
            Coccosteusis a genus of arthrodire placoderm (“arthrodire” means “jointed neck”, withwell developed neck joints between head shield and trunk shield). Its fossilshave been found throughout Europe and North Americain freshwater sediments, although such a large range suggests it may have beenable to enter saltwater. Its average length was 20 – 25 cm, the largestspecimens were about 40 cm.
Pterichthyodesis a genus of placoderm fish from the Devonian period. It had heavily armored heads and front bodies, while theirtail ends were uncovered. As placoderms, they were members of one of the firstgroup of animals to possess jaws, though they had grinding plates rather thanteeth. They are distinguished easily from other placoderms by their oddwing-like appendage where fins would be found on a modern fish("pterichthys" is ancient Greek for “wing-fish”). Pterichthyodes was firstdescribed by the famous Scottish geologist Hugh Miller (1802 – 1856) and bearinghis name in recognition. At the time, these fossils were among the oldestvertebrates ever discovered.

Cheirolepis trailli 
Cheirolepis (“hand-fin”) is an extinct genus of ray-finned fish(Actinopterygians) that lived in the Devonian period of Europe and North America. It was a predatory freshwater fish ofabout 30 cm long, with a streamlined body with small, triangular ganoid scales.It had well-developed fins to give it speed and stability, and was probably andactive predator. Based on the size of its eyes, it hunted by sight. Its jaws,lined with sharp teeth, could be opened very wide, allowing it to swallow preytwo-thirds of its own size. Cheirolepis wasfirst named and described by Agassiz in hisfamous work “Les poissons fossiles”.

Gyroptychius is an extinct genus ofcoelacanthiform lobe-finned fish from the Devonian period. It was a fastriverine predator with an elongated body about 30 cm long. As it eyes wererelatively small, it is presumed to have hunted by smell rather than by sight.It had short jaws which gave it a powerful bite. All its fins except thepectorals were moved to the back of the body, increasing the power of the tailwhile swimming.


    The eurypterids were the largest known arthropods that ever lived. They aremembers of the extinct class Eurypterida. The largest, such as Pterygotus,reached 2 m or more in length, but most species were less than 20 cm. Theywere formidable predators that lived in warm shallow water in the Cambrian toPermian from 510 to 250 million years ago. Eurypterids were the most fearsomeswimming predators of the Paleozoic. Although called "sea scorpions",only the earliest ones were marine (most became brackish or freshwateranimals), and they were not true scorpions. The typical eurypterid had a large,flat, semicircular carapace, followed by a jointed section, and finally atapering, flexible tail, with a long spine at the end. Some eurypterids havepaddles, which were used to propel themselves through water. They had fourpairs of jointed legs for walking, and two small claws at the front. Some species may have been amphibious,emerging onto land for at least part of their life cycle. They may have beencapable of breathing both in water and in air.

THE SILURIAN ERA © Henskens Fossils & John v. Straaten


    Graptolites are fossil colonialanimals known from the Upper Cambrian through the Lower Carboniferous. Eachgraptolite consisted of a stick- or twig-like colony of tiny animals thateither floated in the sea or was attached to the sea floor like a tiny,up-right shrub. The graptolite colony consisted of branches that were straight,curved or spiral. The individual animals lived in a series of tiny, cup-likestructures organised along the length of the graptolite skeleton. They arecommon fossils and have a worldwide distribution. Graptolites are importantindex fossils for dating Paleozoic rocks as they evolved rapidly with time andformed many different species. They are often found in rock having formed fromsediment deposited in deep water that had poor bottom circulation, lackedoxygen and had no scavengers. Graptolites vary in shape, but are often dendriticor branching, saw-blade like, or tuning-fork shaped

THE ORDIVICIAN ERA © Henskens Fossils & John v. Straaten


    Cystoids are an extinct groupof echinoderms, with a typical 5-way pseudosymmetry and body composed ofcalcitic plates. They are animals although they resemble plants. The bodyplates are quite irregular in arrangement, and the arms are irregular andrarely preserved. Attached to the sea bottom by a flexible stem, theirlimy-plated bodies were a a few millimetes to 5 cm in diameter. Numerous smalltentacles extended from their heads to capture microscopic food particles fromsea water. The cystoids lived from the early Ordovian till the midCarboniferous.

THE CAMBRIAN ERA © Henskens Fossils & John v. Straaten


    Paradoxides gracilis (Boeck,1827) belongs to the order Redlichiida. These are primitive trilobites withnumerous thoracic segments with spinose tips. The cephalon is large andsemicircular; the glabella long, well-segmented, tapering or expanding forwards;genal spines are strong, usually continued from a narrow, tubular cephalicborder; eyes large, crescentic, with large, inflated palpebral lobe ridgesrunning toward front of glabella; eye ridge may be subdivided; hypostometypically conterminant, usually very wide rostral plate present. The thorax hasnumerous segments (up to 90+), pleurae usually with spinose tips; may besubdivided into prothorax and opisthothorax. The pygidium is typically tiny(micropygous), with one or very few segments. Trilobites from the orderRedlichiida lived from Middle to Late Cambrian.

THE PRE-CAMBRIANERA © Henskens Fossils & John v. Straaten


    Stromatolites ((from Greek strōma, mattress, bed, stratum, and lithos,rock) are fossils which show the lifeprocesses of cyanobacteria (blue-green algae). The primitive cells (Prokaryotictype, which did not have a nucleus yet), lived in huge masses that could formfloating mats or extensive reefs. Masses of cyanobacteria on the sea floordeposited calcium carbonate in layers or domes. These layered deposits arecalled laminar stromatolites. Stromatolites were abundant in Pre-Cambrian times. ThePrecambrian atmosphere was rich in carbon dioxide, but prior to 2.4 billionyears ago, it lacked the oxygen that sustains the complex multicellular lifethat has evolved since about 600 million years ago. Stromatolites in thegeological record declined sharply in both diversity and number during thelatest Precambrian and are present, but uncommon in modern day marineenvironments.