Hallucigenia is a genus of lobopodian known from Cambrian aged fossils in Burgess Shale-type deposits in Canada 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.
The Maotianshan Shales (帽天山页岩) are a series of Early Cambrian sedimentary deposits in the Chiungchussu Formation, famous for their Konservat Lagerstätten, deposits known for the exceptional preservation of fossilized organisms or traces. The Maotianshan Shales form one of some forty Cambrian fossil locations worldwide exhibiting exquisite preservation of rarely preserved, non-mineralized soft tissue, comparable to the fossils of the Burgess Shale of British Columbia, Canada. They take their name from Maotianshan Hill in Chengjiang County, Yunnan Province, China.
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.
Canadaspis is an extinct genus of bivalved Cambrian 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.
Waptia is an extinct genus of arthropod from the Middle Cambrian of North America. It grew to a length of 6.65 cm (3 in), 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.
Dinomischusis an extinct genus of stalked filter-feeding animals within the Cambrian period, with specimens known from the Burgess Shale and the Maotianshan Shales. While long of uncertain affinities, recent studies have suggested it to be a stem-group ctenophore.
Leanchoilia is a megacheiran arthropod known from Cambrian deposits of the Burgess Shale in Canada and the Chengjiang biota of China.
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. Branchiocaris pretiosa is around 80–90 millimetres (3.1–3.5 in) in length, with a highly segmented trunk, consisting of at least 44 ring-like segments, terminating in a forked tail telson. At the front of the animal is a pair of short segmented tapered antennules with at least 20 segments, as well as a pair of claw appendages. It was likely an active swimmer, and used the claw appendages to bring food to the mouth.
Banffozoa is an extinct class of bilaterians. Most workers place it in the Vetulicolia, but the protostome-like features of some members have motivated ongoing debate. Banffozoa consists of the order Banffiata as well as a dwarf "Form A" that has not been formally described or named. Skeemella has been placed incertae sedis in this class, but has more recently been placed with the Banffiidae. Banffozoa may be paraphyletic even if Vetulicolia is monophyletic.
Plenocaris plena is a genus of extinct bivalved hymenocarine arthropod that lived in the Cambrian aged Burgess Shale and Chengjiang. Originally described as a species of Yohoia by Walcott in 1912, it was placed into its own genus in 1974.
Liangshanella is a genus of Cambrian bradoriid known from the Chengjiang biota and Burgess Shale. 6263 specimens of Liangshanella are known from the Greater Phyllopod bed, where they comprise 11.9% of the community.
Primicaris is genus of Cambrian arthropod from the Chengjiang biota of China and the Burgess Shale of Canada. It contains a single described species, P. larvaformis.
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, Siberia, and in Upper Ordovician strata of Morocco.
Cambrorhytium is an enigmatic fossil genus known from the Latham Shale (California), and the Chengjiang (China) and Burgess Shale lagerstätte. 350 specimens of Cambrorhytium are known from the Greater Phyllopod bed, where they comprise 0.7% of the community.
Mollisonia is an extinct genus of Cambrian arthropod. 4 species had been described from North America and China. Studies suggest it is a basal member of Chelicerata, a group which includes horseshoe crabs and arachnids.
The Cambroernida are a clade of unusual Paleozoic animals with coiled bodies and filamentous tentacles. They include a number of early to middle Paleozoic 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.
Cotyledion tylodes is an extinct, stalked filter-feeder known from the Chengjiang lagerstatten. The living animal reached a couple of centimetres in height, and bore a loose scleritome of ovoid sclerites. Its interpretation has been controversial, but it is currently thought to be a member of the Entoprocta stem group.
Iotuba chengjiangensis is a 515 million year old Cambrian worm known from the Chengjiang biota. Originally interpreted as a phoronid, the organism is now recognized as an annelid cage worm affiliated with the Flabelligeridae and Acrocirridae, which Zhang et al grouped together in the new superfamily Flabelligeroidea.
Acinocricus is a genus of extinct panarthropod belonging to the group Lobopodia and known from the middle Cambrian Spence Shale of Utah, United States. As a monotypic genus, it has one species Acinocricus stichus. The only lobopodian discovered from the Spence Shale, it was described by Simon Conway Morris and Richard A. Robison in 1988. Owing to the original fragmentary fossils discovered since 1982, it was initially classified as an alga, but later realised to be an animal belonging to Cambrian fauna.
Cheungkongella is a fossil organism from the lower Cambrian Chengjiang lagerstatte, the affinity of which has been the subject of debate. It was announced as a "probable" tunicate while noting the lack of definitive Cambrian fossils from that group. However, this affinity was later disputed in a paper announcing the discovery of Shankouclava, also from Chengjiang, as the oldest known tunicate. Cheungkongella has been accepted as a distinct taxon and possible tunicate by multiple workers not involved in its discovery, but the dispute remains unresolved.
