Dinocaridida is a proposed fossil taxon of basal arthropods, which flourished during the Cambrian period and survived up to Early Devonian. Characterized by a pair of frontal appendages and series of body flaps, the name of Dinocaridids refers to the suggested role of some of these members as the largest marine predators of their time. Dinocaridids are occasionally referred to as the 'AOPK group' by some literatures, as the group compose of Radiodonta, Opabiniidae, and the "gilled lobopodians" Pambdelurion and Kerygmachelidae. It is most likely paraphyletic, with Kerygmachelidae and Pambdelurion more basal than the clade compose of Opabiniidae, Radiodonta and other arthropods.
Anomalocarididae is an extinct family of Cambrian radiodonts, a group of stem-group arthropods.
Parapeytoia is a genus of Cambrian arthropod. The type and only described species is Parapeytoia yunnanensis, lived over 518 million years ago in the Maotianshan shales of Yunnan, China. Unidentified fossils from the same genus also had been discovered from the nearby Wulongqing Formation.
Gigoutella is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the Botomian stage, which lasted from approximately 524 to 518.5 million years ago. This faunal stage was part of the Cambrian Period.
Saperion is an extinct genus of trilobite-like arthropod. It lived during the late Atdabanian stage, which lasted from 521 to 514 million years ago during the early part of the Cambrian Period. It was found in the Maotianshan Shales of Yunnan, China. Similar to the closely-related Skioldia and Tegopelte, the head shield and trunk tergites were fused into a single plate. There are about 19 furrows indicating the original trunk segments. a small anterior sclerite articulated to the front of its head. A pair of antennae and lateral eyes located ventrally behind the anterior sclerite, lateral to the hypostome. Saperion reached 151 mm in length and had nearly 25 pairs of biramous limbs for walking.
Acanthomeridion is an extinct arthropod found in the Chengjiang fauna deposits of China. In 1997, it was placed in its own, monotypic family, Acanthomeridiidae. It is known from eight specimens, all found in China.
Megacheira is an extinct class of predatory arthropods defined by their possession of spined "great appendages". Their taxonomic position is controversial, with studies either considering them stem-group euarthropods, or stem-group chelicerates. The homology of the great appendages to the cephalic appendages of other arthropods is also controversial. Uncontested members of the group were present in marine environments worldwide from the lower to middle Cambrian.
Cindarella is genus of trilobite-like Cambrian arthropod known from the Chengjiang biota of China. It is classified in the stem group of trilobites (Artiopoda) in the clade Xandarellida, along with Phytophilaspis, Sinoburius, and Xandarella.
Jianshania is genus of Cambrian arthropod known from the Chengjiang biota, containing the single species J. furfactus. It was described by Luo et al. in 1999. In 2020, a specimen originally assigned to the species was found to represent the separate fuxianhuiid taxon Xiaocaris pending revision of the type specimen.
Radiodonta is an extinct order of stem-group arthropods that was successful worldwide during the Cambrian period. They may be referred to as radiodonts, radiodontans, radiodontids, anomalocarids, or anomalocaridids, although the last two originally refer to the family Anomalocarididae, which previously included all species of this order but is now restricted to only a few species. Radiodonts are distinguished by their distinctive frontal appendages, which are morphologically diverse and used for a variety of functions. Radiodonts included the earliest large predators known, but they also included sediment sifters and filter feeders. Some of the most famous species of radiodonts are the Cambrian taxa Anomalocaris canadensis, Hurdia victoria, Peytoia nathorsti, Titanokorys gainessii, Cambroraster falcatus and Amplectobelua symbrachiata. The later surviving members include the subfamily Aegirocassisinae from the Early Ordovician of Morocco and the Early Devonian member Schinderhannes bartelsi from Germany.
Phytophilaspis is a phosphatized genus of trilobite-like arthropod with eyes, found in association with algal remains. It dwelt in well-lit, shallow waters.
The Luolishaniidae or Luolishaniida are a group of Cambrian and Ordovician lobopodians with anterior 5 or 6 pairs of setiferous lobopods. Most luolishaniids also have posterior lobopods each with a hooked claws, and thorn-shaped sclerites arranged as three or more per trunk segment. The type genus is based on Luolishania longicruris Hou and Chen, 1989, from the Chengjiang Lagerstatte, South China. They are presumed to have been benthic suspension or filter feeders.
Chengjiangocaris is an extinct genus of fuxianhuiid arthropod known from the Cambrian of South China. It contains two species, C. longiformis which was described in 1991. C. kunmingensis was described in 2013 by Javier Ortega-Hernández and colleagues. One specimen of C. kunmingensis shows detailed evidence of a nervous system. The nervous system of the chengjiangocaris is and has always been very complex to understand but a recent discovery of the ladder like ventral nerval cords and segmental ganglia of the related chengjiangocaris together with the brain provide the most comprehensive reconstruction of any lower Cambrian arthropod.
The Artiopoda is a grouping of extinct arthropods that includes trilobites and their close relatives. It was erected by Hou and Bergström in 1997 to encompass a wide diversity of arthropods that would traditionally have been assigned to the Trilobitomorpha. Trilobites, in part due to abundance of findings owing to their mineralized exoskeletons, are by far the best recorded, diverse, and long lived members of the clade. Other members, which lack mineralised exoskeletons, are known mostly from Cambrian deposits.
Squamacula is an extinct artiopodan arthropod from the Cambrian Series 2. The type species S. clypeata was described in 1997 from the Chengjiang biota of Yunnan, China. At the time of description there were only two known specimens of S. clypeata, but now there are at least six known specimens. In 2012 a second species S. buckorum was described from the Emu Bay Shale of Australia.
Sinoburius is an extinct genus of xandarellid artiopodan known from the Cambrian aged Chengjiang Biota of China. It is only known from the type species S. lunaris, which was described in 1991. It is a rare fossil within the Chengjiang assemblage. Like other Xandarellids, Sinoburius has an unmineralised exoskeleton. Adult individuals are around 7-8 millimetres in length, with stalked eyes present on the ventral side. Unusually among artiopods, the antennae are strongly reduced in size.
Luohuilinella is an extinct genus of xandarellid artiopodan arthropod known from the Chengjiang biota of China. The type species Luohuilinella rarus was described in 2012. A second species Luohuilinella deletres was described in 2018. Both taxa are rare components of the assemblage. Like other Xandarellids and most artiopodans, it possessed an unmineralised exoskeleton. The type and currently only known specimen of L. rarus is known from a dorsal exoskeleton, around 17 mm long and 9 mm wide which consists of 27 tergites with pronounced pleural spines. L. deletres is much larger, with specimens being over 10 cm long, L. deletres possessed at least 11 pairs of biramous appendages. Both taxa are dorsoventrally flattened, making a benthic or nektobenthic lifestyle probable. Both taxa have pronounced notches in the cephalon to accommodate the stalked eyes.
Retifacies abnormalis is an extinct arthropod that lived in the lower Cambrian. Its fossil remains have been found in the Maotianshan Shales of Yunnan, China. It is a member of the Artiopoda, and closely related to Pygmaclypeatus.
Fuxianhuiida is an extinct clade of arthropods from the Cambrian of China. All currently known species are from Cambrian Series 2 aged deposits in Yunnan Province, including the Chengjiang biota. Although historically suggested to be members of the arthropod stem group recent research has suggested that they may be closely related to mandibulates. Many specimens are known with exceptional soft tissue preservation, including preserved guts and neural tissue, which given their basal phylogenetic position makes them important in understanding the evolution of Arthropoda as a whole. They reach a size of up to 15 cm, and are interpreted as benthic predators and scavengers. The Fuxianhuiid exoskeleton is unmineralised, and the number of tergites ranges from 15 to over 40. The cephalon is covered by a head shield and contains stalked eyes connected by the anterior sclerite, antennae, a butterfly shaped hyposome and a posterior facing mouth. Fuxianhuiids possess specialized post-antennal appendages with serrated edges used for food processing. The presence of gnathobases in members of Chengjiangocardidae suggests that they were capable of durophagy. In most Fuxianhuiids, the thorax tergites narrow posteriorly, terminating in either a swimming paddle or paired flukes with a tail spine. In members of Fuxianhuiidae the thorax is divided into two sections, the anterior wide opisthothorax and the posterior narrow limbless tail-like abdomen.
Luolishania is an extinct genus of lobopodian panarthropod and known from the Lower Cambrian Chiungchussu Formation of the Chengjiang County, Yunnan Province, China. A monotypic genus, it contains one species Luolishania longicruris. It was discovered and described by Hou Xian-Guang and Chen Jun-Yuan in 1989. It is one of the superarmoured Cambrian lobopodians suspected to be either an intermediate form in the origin of velvet worms (Onychophora) or basal to at least Tardigrada and Arthropoda. It is the basis of the family name Luolishaniidae, which also include other related lobopods such as Acinocricus, Collinsium, Facivermis, and Ovatiovermis. Along with Microdictyon, it is the first lobopodian fossil discovered from China.
