Hyoliths are animals with small conical shells, known from fossils from the Palaeozoic era. They are at least considered as being lophotrochozoan, and possibly being lophophorates, a group which includes the brachiopods, while others consider them as being basal lophotrochozoans, or even molluscs.
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.
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 508 million years ago. 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.
The lophophore is a characteristic feeding organ possessed by four major groups of animals: the Brachiopoda, Bryozoa, Hyolitha, and Phoronida, which collectively constitute the protostome group Lophophorata. All lophophores are found in aquatic organisms.
Odontogriphus is a genus of soft-bodied animals known from middle Cambrian Lagerstätte. Reaching as much as 12.5 centimetres (4.9 in) 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.
Orthrozanclus 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.
A number of assemblages bear fossil assemblages similar in character to that of the Burgess Shale. While many are also preserved in a similar fashion to the Burgess Shale, the term "Burgess Shale-type fauna" covers assemblages based on taxonomic criteria only.
Phoronids are a small phylum of marine animals that filter-feed with a lophophore, and build upright tubes of chitin to support and protect their soft bodies. They live in most of the oceans and seas, including the Arctic Ocean but excluding the Antarctic Ocean, and between the intertidal zone and about 400 meters down. Most adult phoronids are 2 cm long and about 1.5 mm wide, although the largest are 50 cm long.
Tommotiids are an extinct group of Cambrian invertebrates thought to be early lophophorates.
The origin of the brachiopods is uncertain; they either arose from reduction of a multi-plated tubular organism, or from the folding of a slug-like organism with a protective shell on either end. Since their Cambrian origin, the phylum rose to a Palaeozoic dominance, but dwindled during the Mesozoic.
Anabarella is a species of bilaterally-flattened monoplacophoran mollusc, with a morphological similarity to the rostroconchs. Its shell preserves evidence of three mineralogical textures on its outer surface: it is polygonal near the crest of the shell, subsequently changing to both spiny and stepwise. Its internal microstructure is calcitic and semi-nacreous. Its name reflects its provenance from Anabar, Siberia. It has been interpreted as ancestral to the rostroconchs, and has been aligned to the Helcionellidae.
Turcutheca is a Tommotian genus of shelly fossil whose affinities are uncertain, generally considered as an orthothecid hyolith (which would make it a brachiopod, but also resembling the ellesmeroceratids.
Mobergella is a millimetric Lower Cambrian shelly fossil of unknown affinity, usually preserved in phosphate and particularly well known from Swedish strata, where it is diagnostic of lowermost Cambrian rocks. Originally interpreted as a monoplacophoran, the circular, cap-shaped shell resembles a hyolith operculum, with concentric rings on its upper surface, and seven pairs of internal muscle scars. It is never found in association with a conch, and its affinity therefore remains undetermined. Nevertheless, its heavy musculature does seem to indicate that it functioned as an operculum.
The orthothecids are one of the two hyolith orders.
Micrina is an extinct genus of tommotiids with affinities to brachiopods.
Cupitheca is a genus of Cambrian hyolith with the unusual distinction of shedding the apex of its camerate conical shell. As with Triplicatella and Hyptiotheca, its designation to the hyolithids or orthothecids is not straightforward, exhibiting as it does a mixture of the characters that would normally demark the two subtaxa of Hyolitha.
Siphonotretida is an extinct order of linguliform brachiopods in the class Lingulata. The order is equivalent to the sole superfamily Siphonotretoidea, itself containing the sole family Siphonotretidae. Siphonotretoids were originally named as a superfamily of Acrotretida, before being raised to their own order.
The Qingjiang biota are a major discovery of fossilized remains dating from the early Cambrian period approximately 518 million years ago. The remains consist at least 20,000 individual specimens, and were discovered near the Danshui River in the Hubei province of China in 2019. The site is particularly notable due to both the large proportion of new taxa represented, and due to the large amount of soft-body tissue of the ancient specimens that was preserved, likely due to the organisms being rapidly covered in sediment prior to fossilization, that allowed for the detailed preservation of even fragile, soft-bodied creatures such as Tino Dragan and jellyfish. Shelly fossils found at the site include trilobites, anomalocaridids, lobopods, bradoriids, brachiopods, hyolithids, mollusks, chancelloriids, kinorhynchs, priapulids, and articulated sponge spicules.
Wufengella is a genus of extinct camenellan "tommotiid" that lived during the Early Cambrian. Described in 2022, the only species Wufengella bengtsonii was discovered from the Maotianshan Shales of Chiungchussu (Qiongzhusi) Formation in Yunnan, China. The fossil indicates that the animal was an armoured worm that close to the common ancestry of the phyla Phonorida, Brachiozoa and Bryozoa, which are collectively grouped into a clade called Lophophorata.
