Burgess Shale fossils

Anomalocaris (from Ancient Greek , meaning "unlike", and , meaning "shrimp", with the intended meaning "unlike other shrimp") is an extinct genus of radiodont, an order of early-diverging stem-group marine arthropods. It is best known from the type species A. canadensis, found in the Stephen Formation (particularly the Burgess Shale) of British Columbia, Canada. The other named species A. daleyae is known from the somewhat older Emu Bay Shale of Australia. Other unnamed Anomalocaris species are known from China and the United States.

Opabinia regalis is an extinct, stem group marine arthropod found in the Middle Cambrian Burgess Shale Lagerstätte (505 million years ago) of British Columbia. Opabinia was a soft-bodied animal, measuring up to 7 cm in body length, and had a segmented trunk with flaps along its sides and a fan-shaped tail. The head showed unusual features: five eyes, a mouth under the head and facing backwards, and a clawed proboscis that most likely passed food to its mouth. Opabinia lived on the seafloor, using the proboscis to seek out small, soft food. Fewer than twenty good specimens have been descri

fossil-bearing rock formation in the Canadian Rockies

Hallucigenia is a genus of lobopodian known from Cambrian-aged fossils in Burgess Shale-type deposits in Canada (Burgess Shale) and China, and from isolated spines around the world. The generic name reflects the type species' unusual appearance and eccentric history of study; when it was erected as a genus, H. sparsa was reconstructed as an enigmatic animal upside down and back to front. Lobopodians are a grade of Paleozoic panarthropods from which the velvet worms, water bears, and arthropods arose.

Wiwaxia is a genus of prehistoric soft-bodied animals that were covered in carbonaceous scales and spines that protected it from predators. Wiwaxia fossils—mainly isolated scales, but sometimes complete, articulated fossils—are known from early Cambrian and middle Cambrian fossil deposits across the globe. The living animal would have measured up to when fully grown, although a range of juvenile specimens are known, the smallest being long.

museum in Alberta, Canada

Aysheaia is an extinct genus of soft-bodied lobopodian, known from the Middle Cambrian Burgess Shale of British Columbia, Canada.

Hurdia is an extinct genus of hurdiid radiodont that lived 505 million years ago during the Cambrian Period. Fossils have been found in North America, China, and the Czech Republic.

Marrella is an extinct genus of marrellomorph arthropod known from the Middle Cambrian of North America and Asia. It is the most common animal represented in the Burgess Shale of British Columbia, Canada, with tens of thousands of specimens collected. Much rarer remains are also known from deposits in China.

Ottoia is a stem-group archaeopriapulid worm known from Cambrian fossils. Although priapulid-like worms from various Cambrian deposits are often referred to Ottoia on spurious grounds, the only clear Ottoia macrofossils come from the Burgess Shale of British Columbia, which was deposited . Microfossils extend the record of Ottoia throughout the Western Canada Sedimentary Basin, from the mid- to late Cambrian. A few fossil finds are also known from China.

Peytoia is a genus of hurdiid radiodont, an early diverging order of stem-group arthropods, that lived in the Cambrian period, containing two species, Peytoia nathorsti from the Miaolingian of Canada and Peytoia infercambriensis from Poland, dating to Cambrian Stage 3. Its two frontal appendages had long bristle-like spines, it had no fan tail, and its short stalked eyes were behind its large head.

Sanctacaris is a Middle Cambrian arthropod from the Burgess Shale of British Columbia. It was most famously regarded as a stem-group chelicerate, a group which includes horseshoe crabs, spiders and scorpions, although subsequent phylogenetic studies have not always supported this conclusion. Its chelicerate affinities regain support in later observations, alongside the reassignment of Habelia optata as a sanctacaridid-related basal chelicerate. It has been placed as a member of the extinct family Sanctacarididae alongside Wisangocaris and Utahcaris.

Amplectobelua (meaning "embracing beast") is an extinct genus of late Early Cambrian amplectobeluid radiodont, a group of stem arthropods that mostly lived as free-swimming predators during the first half of the Paleozoic Era.

Alalcomenaeus is one of the most widespread and longest-surviving arthropod genera of the Early and Middle Cambrian. Known from over 300 specimens in the Burgess Shale and the Chengjiang biota. It is a member of the family Leanchoiliidae in the group Megacheira.

Sidneyia is an extinct marine arthropod known from fossils found from the Early to the Mid Cambrian of China and the Mid Cambrian Burgess Shale of British Columbia, Canada. It is thought to have been a durophagous (crushing) predator that used its spine-covered leg bases (gnathobases) to feed on hard-bodied animals like trilobites and brachiopods, as well as possibly soft bodied animals. It was historically placed in the group "Xenopoda" alongside Emeraldella. It is now placed within the clade Vicissicaudata along with aglaspidids, chelonellids, as well as Emeraldella, among others. Vicissicau

Amiskwia is a genus of soft-bodied marine animals known from fossils of the Middle Cambrian Lagerstätten both in the Burgess Shale in British Columbia, Canada and the Maotianshan shales of Yunnan Province, China. It is interpreted as a member of the clade Gnathifera sensu lato or as a basal cucullophoran.

Stanleycaris ("Stanley's shrimp") is an extinct genus of hurdiid radiodont from the Cambrian (Stage 3 to Miaolingian). The type species is Stanleycaris hirpex. Stanleycaris was described from the Stephen Formation near the Stanley Glacier and Burgess Shale locality of Canada, as well as Wheeler Formation of United States. A second species, S. qingjiangensis is known from the Qingjiang biota of China. The genus was characterized by the rake-like frontal appendages with robust inner spines.

Canadaspis ("Shield of Canada") is an extinct genus of bivalved Cambrian marine arthropod, known from North America and China. They are thought to have been benthic feeders that moved mainly by walking and possibly used its biramous appendages to stir mud in search of food. They have been placed within the Hymenocarina, which includes other bivalved Cambrian arthropods.

300px|left|thumb|Reconstruction of the head region of Cambroraster falcatus. A: Dorsal view, B: Ventral view, Ey: Eye, Fa: Frontal appendage, He:H-element, Bp: Bilobate posterior region, Lp: Posterolateral process, Oc: Oral cone, Pe: P-element, Pn: P-element neck Cambroraster is an extinct monotypic genus of hurdiid radiodont, dating to the middle Cambrian, and represented by the single formally described species Cambroraster falcatus. Hundreds of specimens were found in the Burgess Shale, and described in 2019. A large animal (for its era) at up to (but not as long as Titanokorys at ), it is

Leanchoilia is a megacheiran marine arthropod known from Cambrian deposits of the Burgess Shale in Canada and the Chengjiang biota of China.

Metaspriggina is a genus of chordate initially known from two specimens in the Middle Cambrian Burgess Shale and 44 specimens found in 2012 at the Marble Canyon bed in Kootenay National Park.

Burgessochaeta is an extinct genus of polychaete annelids from the Middle Cambrian. Its fossils have been found in the Burgess Shale in British Columbia, Canada. The genus was described by Conway Morris (1979) and re-examined by Eibye-Jacobsen (2004).

Yohoia is an extinct genus of fossil megacheiran arthropod from the Cambrian period. The type species, Yohoia tenuis, has been found in the Burgess Shale formation of British Columbia. 711 specimens of Yohoia are known from the Greater Phyllopod bed, where they comprise 1.35% of the community. In 2015, Conway Morris et al. reported another species, Y. utahana, from the Marjum Formation, Utah.

Waptia is an extinct genus of marine arthropod from the Middle Cambrian of North America. It grew to a length of , and had a large bivalved carapace and a segmented body terminating into a pair of tail flaps. It was an active swimmer and likely a predator of soft-bodied prey. It is also one of the oldest animals with direct evidence of brood care. Waptia fieldensis is the only species classified under the genus Waptia, and is known from the Burgess Shale Lagerstätte of British Columbia, Canada. Specimens of Waptia are also known from the Spence Shale of Utah, United States.

Dinomischus is an extinct genus of stalked filter-feeding animals within the Cambrian period, with specimens known from the Burgess Shale, the Maotianshan Shales, the Kaili Formation and the Marjum Formation. While long of uncertain affinities, recent studies have suggested it to be a stem-group ctenophore.

Titanokorys is a genus of extinct hurdiid (peytoiid) radiodont (a grouping of primitive stem arthropods which lived during the early Paleozoic) that lived during the Miaolingian epoch of the middle Cambrian. It is the largest member of its family from the Cambrian, with an estimated body length of around long, making it one of the largest animals of the time. It bears a resemblance to the related, and contemporary, genus Cambroraster. Fossils of T. gainesi were first found within the Marble Canyon locality of the Burgess Shale in 2018, however the fossils were not named until 2021 because they

Odaraia is an extinct genus of bivalved hymenocarine arthropod with a single known species Odaraia alata, found in the Middle Cambrian Burgess Shale in British Columbia, Canada.

Mollisonia is an extinct genus of Cambrian marine arthropod. Four species have been described from North America and China. Studies suggest it is a basal member of Chelicerata, a group which includes horseshoe crabs and arachnids.

Eldonia is an extinct soft-bodied cambroernid best known from the Fossil Ridge outcrops of the Burgess Shale, particularly in the 'Great Eldonia layer' in the Walcott Quarry. In addition to over 550 specimens collected by Walcott, 224 specimens of Eldonia are known from the Greater Phyllopod bed, where they comprise 0.43% of the community. Species also occur in the Chengjiang biota, and Siberia.

Odontogriphus (from , 'tooth' and , 'riddle') is a genus of soft-bodied animals known from middle Cambrian Lagerstätte. Reaching as much as in length, Odontogriphus is a flat, oval bilaterian which apparently had a single muscular foot and a "shell" on its back that was moderately rigid but of a material unsuited to fossilization.

thumb|right|250px|Elrathia kingii growth series with holaspids ranging from 16.2 mm to 39.8 mm in length

Olenoides is a genus of trilobite from the Cambrian period. Its fossils can be found with soft body parts intact in the Burgess Shale in Canada. Fossils of this genus can also be found in the Wheeler Shale and Marjum Formation of Utah in the United States of America, among other localities. Species within this genus range in size, with most being medium-sized trilobites (Olenoides Serratus from the Burgess Shale can be up to 9 centimeters in length). Specimens of Olenoides Superbus, pictured on the right, an especially large species, can reach sizes of well over 10 centimeters in length. Oleno

thumb|Haplophrentis carinatus from the Stephen Formation, Burgess Shale (Middle Cambrian), Burgess Pass, British Columbia, Canada. Haplophrentis is a genus of tiny shelled hyolithid which lived in the Cambrian Period. Its shell was long and conical, with the open end protected by an operculum, from which two fleshy arms called helens protruded at the sides. These arms served to elevate the opening of the shells above the sea floor, acting like stilts.

Isoxys (meaning "equal surfaces") is a genus of extinct bivalved Cambrian arthropod; the various species of which are thought to have been freely swimming predators. It had a pair of large spherical eyes (which are the most commonly preserved feature of the soft-bodied anatomy), and two large frontal appendages used to grasp prey.

Lingulella is a genus of phosphatic-shelled brachiopod. It is known from the Middle Cambrian Burgess Shale (Canada) to the Upper Ordovician Bromide Formation (United States) in North America. 346 specimens of Lingulella are known from the Greater Phyllopod bed, where they comprise 0.66% of the community.

Tuzoia (from Mount Tuzo, a mountain in the Canadian Rockies) is an extinct genus of large bivalved arthropod known from Early to Middle Cambrian marine environments from what is now North America, Australia, China, Europe and Siberia. The large, domed carapace reached lengths of , making them amongst the largest known Cambrian arthropods.

Sarotrocercus is a small Cambrian arthropod known from Burgess Shale, reaching a centimetre or two in length (). Sarotrocercus is only known from 7 specimens. It may lie in the arthropod crown group, and a recent study has revised some points of its original description.

Siphusauctum, also known as the tulip animal, is an extinct genus of filter-feeding animals that lived during the Middle Cambrian.

Burgessia is a genus of arthropod known from the mid-Cambrian aged Burgess Shale of British Columbia, Canada. It is relatively abundant, with over 1,700 specimens having been collected.

Habelia is a genus of extinct arthropod from the Middle Cambrian, thought to be one of the earliest known relatives of chelicerates. Its fossils have been found in the Burgess Shale in British Columbia, Canada. Fifty-four specimens of Habelia are known from the Greater Phyllopod bed, where they comprise 0.1% of the community.

Perspicaris (from the Latin perspicax, meaning “sharp-sighted,” and caris, “crab/shrimp”) an extinct genus of bivalved arthropod from the Cambrian period. Fossils have been found in North America, primarily the Burgess Shale of British Columbia, Canada but also possibly the Wheeler Shale, Marjum Formation, Pioche Shale and Bloomington Formation. Two named species are known from the Burgess Shale Perspicaris dictynna and Perspicaris recondita, which differ in maximum size ( in P. recondita vs in P. dictynna), as well as proportions of the tail. Both species have a pair of stalked eyes, as well

Orthrozanclus (from Greek + ( + ), "dawn scythe") is a genus of sea creatures known from two species, O. reburrus from the Middle Cambrian (~) Burgess Shale and O. elongata from Early Cambrian (~) Maotianshan Shales. Animals in this genus were one to two centimeters long, with spikes protruding from their armored bodies. The placement of this genus into a specific family is not universally accepted.

Ogygopsis is a genus of trilobite from the Cambrian of Antarctica and North America, specifically the Burgess Shale. It is the most common fossil in the Mt. Stephen fossil beds there, but rare in other Cambrian faunas. Its major characteristics are a prominent glabella with eye ridges, lack of pleural spines, a large spineless pygidium about as long as the thorax or cephalon, and its length: up to 12 cm. File:Ogygopsis reconstruction.jpg|Reconstruction of Ogygopsis klotzi in the Burgess Shale File:Royal Tyrrell Ogygopsis klotzi.jpg|At the Royal Tyrrell Museum of Palaeontology

Hymenocaris is a genus of Cambrian marine arthropod. The type species, Hymenocaris vermicaudata is known from the Upper Cambrian (Furongian) Ffestiniog Formation, in North Wales, United Kingdom.

Helmetia is an extinct genus of arthropods from the middle Cambrian (Wuliuan). Fossils of the type species Helmetia expansa have been found in the Burgess Shale of Canada. It is characterized by a pair of spines in front of its head. It is classified under Conciliterga, a group of trilobitomorph artiopod.

Echmatocrinus brachiatus is an extinct species of Cambrian animal which resembles a crinoid or an octocoral. Its exact taxonomy is still a subject of debate. It is known only from the Burgess Shale. Around 20 specimens of Echmatocrinus are known; these comprise <0.02% of the community.

thumb|left|Kootenia assemblage at the Geological Museum in Copenhagen

Hallucigeniidae is a family of extinct panarthropods belonging to the group Lobopodia that originated during the Cambrian explosion. It is based on the species Hallucigenia sparsa, the fossil of which was discovered by Charles Doolittle Walcott in 1911 from the Burgess Shale of British Columbia. The name Hallucigenia was created by Simon Conway Morris in 1977, from which the family was erected after discoveries of other hallucigeniid worms from other parts of the world. Classification of these lobopods and their relatives are still controversial, and the family consists of at least four genera

Louisella is a genus of worm known from the Middle Cambrian Burgess Shale. It was originally described by Charles Walcott in 1911 as a holothurian echinoderm, and represents a senior synonym of Miskoia, which was originally described as an annelid. 48 specimens of Louisella are known from the Greater Phyllopod bed, where they comprise < 0.1% of the community. It has been stated to have palaeoscolecid-like sclerites, though this is not in fact the case.

Selkirkia is a genus of predatory, tubicolous priapulid worms known from the Middle Cambrian Burgess Shale, Ogygopsis Shale, Puncoviscana Formation and the Early Ordovician Fezouata Formation. 142 specimens of Selkirkia are known from the Greater Phyllopod bed, where they comprise 0.27% of the community. In the Burgess Shale, 20% of the tapering, organic-walled tubes are preserved with the worm inside them, whereas the other 80% are empty (or sometimes occupied by one or more small agnostid trilobites). Whilst alive, the tubes were probably vertical, whereas trilobite-occupied tubes are horizo

genus of radiodonts

Skania is a Cambrian fossil arthropod. The type species, S. fragillis, is known from the Burgess Shale of British Columbia, Canada. A second possible species "S." sundbergi is known from the Kaili Formation of China, but its placement within the genus has been questioned.

The Cambroernida are a clade of Paleozoic animals with coiled bodies and filamentous tentacles. They include a number of early to middle Paleozoic (Cambrian to Devonian) genera noted as "bizarre" or "orphan" taxa, meaning that their affinities with other animals, living or extinct, have long been uncertain. While initially defined as an "informal stem group," later work with better-preserved fossils has strengthened the argument for Cambroernida as a monophyletic clade.

Emeraldella is a genus of arthropod known from the Middle Cambrian of North America. The type species E. brocki was described in 1912 from the Burgess Shale. 21 specimens of Emeraldella are known from the Greater Phyllopod bed, where they comprise < 0.1% of the community. A re-study on the species was done in 2012. A second species E. brutoni is known from the Wheeler Shale, which was described in 2011. An additional specimen of E. brutoni was described in 2019, which revealed more of the anatomy. It has been placed as a basal member of the clade Vicissicaudata within Artiopoda, a group of art

Branchiocaris is an extinct genus of Cambrian bivalved arthropod. The type and best known species, Branchiocaris pretiosa, was described from the Burgess Shale of British Columbia, Canada, in 1929, originally placed in Protocaris, and was placed into its own distinct genus by Briggs in 1976. Several other possible species have been described from Cambrian deposits in China, and it is also possibly known from Cambrian deposits in Utah.

Balhuticaris is a genus of extinct bivalved (referring to the carapace) hymenocarine arthropod that lived in the Cambrian aged Burgess Shale in what is now British Columbia around 506 million years ago. This extremely multisegmented (with over 100 segments) arthropod is the largest member of the group, and it was even one of the largest animals of the Cambrian, with individuals reaching lengths of 245&nbsp;mm (9&nbsp;in). Fossils of this animal suggests that gigantism occurred in more groups of Arthropoda than had been previously thought. It also presents the possibility that bivalved arthropo

thumb|left|Life restoration Fibulacaris is a monotypic genus of fossil arthropod known only by one species, Fibulacaris nereidis, discovered from the Cambrian Burgess Shale of Canada. It was characterized by a bivalved carapace with an inverted rostrum, sandwiching the slender body with stalked eyes and homonomous appendages. It was probably an actively swimming filter feeder and possibly swam upside-down like some branchiopod crustaceans and horseshoe crabs. Phylogenetic analysis suggest it was a relative or member of Hymenocarina, which contains other bivalved arthropods.

Scenella is an extinct genus of fossil invertebrate animal which is generally considered to be a mollusc; at various times it has been suggested that this genus belongs with the gastropods, the monoplacophorans, or the helcionellids, although no firm association with any of these classes has been established. An affinity with the hydrozoa (as a flotation device) has been considered, although some authors oppose this hypothesis. A gastropod affinity is defended on the basis of six pairs of internal muscle scars, whilst the serially-repeated nature of these scars suggests to other authors a mono

extinct species of priapulid worms

Molaria is a genus of Cambrian arthropod, the type species M. spinifera is known from the Middle Cambrian Burgess Shale. 144 specimens of Molaria are known from the Greater Phyllopod bed, where they comprise 0.27% of the community. A second species M. steini was described from the Sirius Passet in Greenland in 2017.