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Didazoonids
Didazoonidae is a vetulicolian family (biology), family within the order (biology), order Vetulicolata. It is characterized by a relatively thin-walled, non-biomineralized body and a large, round anterior opening surrounded by an oral disc. It may be paraphyletic, even if the phylum Vetulicolia is monophyletic. Description Didazoonids have an ovoid to subquadrate anterior section divided into six subdivisions marked by five circumventing lines perpendicular to the body axis. Cowl-shaped lateral pouches appear along each side of the anterior section, coincident with the five dividing lines. The anterior opening is large, round, and surrounded by a circumventing oral disc. The posterior section has seven segments, which in some species each carry up to six annulations. Taxonomy Didazoonidae was erected to group ''Didazoon''. ''Xidazoon''. and ''Pomatrum'', although ''Xidazoon'' has since been shown to be a junior synonym of ''Pomatrum''. ''Yuyuanozoon'' was moved to the Didazo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Didazoon Haoae
''Didazoon haoae'' is an extinct species of vetulicolid vetulicolian described by Shu, et al. based on fossils found in the Qiongzhusi (Chiungchussu) Formation, Yu'anshan Member (Eoredlichia zone), Early Cambrian, Lower Cambrian, in the Dabanqiao area (Kunming), about 60 km northwest of Chengjiang, China. Etymology "Dida" abbreviates (in Chinese) the China University of Geosciences (other), China University of Geosciences. Description The fossils show that the body of the animal was covered in a thin, flexible cuticle. The anterior part of the body was divided into six Segment (biology), segments, with fairly broad membranes separating the segments, and the Posterior (anatomy), posterior part of the body was divided into seven segments. The constriction between the anterior and posterior parts of the animal shows creasing, and the authors hypothesize that it was quite flexible. The fossils are interpreted as showing a large anterior opening, presumably a mouth, a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chordates
A chordate ( ) is a bilaterian animal belonging to the phylum Chordata ( ). All chordates possess, at some point during their larval or adult stages, five distinctive physical characteristics ( synapomorphies) that distinguish them from other taxa. These five synapomorphies are a notochord, a hollow dorsal nerve cord, an endostyle or thyroid, pharyngeal slits, and a post- anal tail. In addition to the morphological characteristics used to define chordates, analysis of genome sequences has identified two conserved signature indels (CSIs) in their proteins: cyclophilin-like protein and inner mitochondrial membrane protease ATP23, which are exclusively shared by all vertebrates, tunicates and cephalochordates. These CSIs provide molecular means to reliably distinguish chordates from all other animals. Chordates are divided into three subphyla: Vertebrata (fish, amphibians, reptiles, birds and mammals), whose notochords are replaced by a cartilaginous/ bony axial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ooedigera
''Ooedigera peeli'' is an extinct vetulicolian from the Early Cambrian of North Greenland. The front body was flattened horizontally, oval-shaped, likely bearing a reticulated or anastomosing pattern, and had 5 evenly-spaced gill pouches along the midline. The tail was also bulbous and flattened horizontally, but was divided into 7 plates connected by flexible membranes, allowing movement. ''Ooedigera'' likely swam by moving side-to-side like a fish. It may have lived in an oxygen minimum zone alongside several predators in an ecosystem based on chemosynthetic microbial mats, and was possibly a deposit or filter feeder living near the seafloor. Etymology The genus name ''Ooedigera'' derives from Ancient Greek ''ooedis'' "egg-shaped/oval" and ''geros'' "old". The species name ''peeli'' is in honour of Professor John S. Peel from the Geological Survey of Greenland, who especially researched the locality ''Ooedigera'' was discovered in. Taxonomy The type specimen MGUH 29279 wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beidazoon
''Beidazoon venustum'' is a marine deuterostome from the group Vetulicolia. It originates from the lower Cambrian Chengjiang biota of Yunnan Province, China, and was discovered in 2005. It is known as the smallest described vetulicolian, and for its surface being covered in many small nodes. Description ''Beidazoon venustum'' had a hard outer shell similar to ''Vetulicola'', with a single band mouth. Its tail is asymmetrical and composed of a hard shell extending from the upper posterior, an axial lobe of seven segments, and a ventral lobe with four or five segments. According to its discoverer, ''Beidazoon's'' shell was "beautifully ornamented with numerous nodes". Taxonomy The family Beidazoonidae was erected to house ''Beidazoon'' at the time of its discovery. However, ''Beidazoons junior synonym ''Bullivetula'' was assigned to Vetulicolidae Vetulicolidae is a vetulicolian family from the Cambrian Stage 3 Maotianshan Shale and Sirius Passet Lagerstätte that consists of ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vetulicola
''Vetulicola'' is an extinct genus of marine animal discovered from the Cambrian of China. It is the eponymous member of the enigmatic taxon Vetulicolia, which is of uncertain affinities but may belong to the deuterostomes. The name was derived from ''Vetulicola cuneata,'' the first species described by Hou Xian-guang in 1987 from the Lower Cambrian Chiungchussu Formation in Chengjiang, China. Etymology ''Vetulicola'' is a compound Latin word composed of ''vetuli'', meaning "old," or "ancient," and ''cola'', meaning "inhabitant." Description The type species, ''Vetulicola cuneata'', as originally described by Hou Xian-guang in 1987, has a body plan similar to those of arthropods and composed of two distinct parts of approximately equal length. The anterior part is rectangular with a carapace-like structure of four rigid cuticular plates, with a large mouth at the front end. The posterior section is slender, strongly cuticularised and placed dorsally. Paired openings connecti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pikaia
''Pikaia gracilens'' is an extinct, primitive chordate marine animal known from the Middle Cambrian Burgess Shale of British Columbia. Described in 1911 by Charles Doolittle Walcott as an annelid, and in 1979 by Harry B. Whittington and Simon Conway Morris as a chordate, it became "the most famous early chordate fossil", or "famously known as the earliest described Cambrian chordate". It is estimated to have lived during the latter period of the Cambrian explosion. Since its initial discovery, more than a hundred specimens have been recovered. The body structure resembles that of the lancelet and it swam perhaps much like an eel. A notochord and myomeres (segmented blocks of skeletal muscles) span the entire length of the body, and are considered the defining signatures of chordate characters. Its primitive nature is indicated by the body covering, a cuticle, which is characteristic of invertebrates and some protochordates. A reinterpretation in 2024 found evidence of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cathaymyrus
''Cathaymyrus'' is a genus of Early Cambrian chordate known from the Chengjiang biota in Yunnan Province, China. Both species have a long segmented body with no distinctive head. The segments resemble v-shaped muscle blocks found in cephalochordates such as ''Amphioxus''. A long linear impression runs along the "back" of the body looking something like a chordate notochord. While some authors have suggested that the genus is a cephalochordate and closely related to living lancelets, other authors have disputed this due to the poor preservation of the head region, considering its placement within Chordata uncertain. See also * Maotianshan shales The Maotianshan Shales () are a series of Early Cambrian sedimentary deposits in the Chiungchussu Formation or Heilinpu Formation, famous for their '' Konservat Lagerstätten'', deposits known for the exceptional preservation of fossilized orga ... * '' Haikouichthys'' * '' Myllokunmingia'' References {{Taxonbar, from=Q19890829 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yunnanozoon
''Yunnanozoon lividum'' (Yunnan + Greek ζῷον ''zôion'' (animal), with species name Latin ''lividum''; (lead-coloured), referring to preserved colour of specimens) is an extinct species of bilaterian animal from the Lower Cambrian Chengjiang biota of Yunnan province, China. Its affinities have been long the subject of controversy. Description The body of ''Yunnanozoon'' was fusiform, with specimens ranging from in length. The body was strongly laterally compressed, meaning that it was taller than it was wide. A segmented dorsal unit was present on the top of the body. The first segment of which was triangular, while the other segments were approximately rectangular. Axial stripes also ran down the body in the region immediately below the dorsal unit. Towards the front of the animal were 7 pairs of filamentous arches. These arches were covered by sac-like structures which had openings between them. Towards the back of the body a tube-like structure was present, possibly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vetulicolidae
Vetulicolidae is a vetulicolian family from the Cambrian Stage 3 Maotianshan Shale and Sirius Passet Lagerstätte that consists of ''Vetulicola'', ''Beidazoon'', and ''Ooedigera''. It is distinguished from the Didazoonidae by a harder body wall and the lack of an oral disc. Description Members of the Vetulicolidae have relatively robust body coverings, with a subquadrate to elongate (in lateral view) anterior part and an elongate, segmented posterior part. The marginal zone of the anterior part may have short projections dorsally and postereodorsally. As diagnosed by Aldridge ''et al.'' in 2007, the anterior part is said to bear five annulations, and a lateral groove is not mentioned for the family. However, with and the addition of ''Ooedigera'' not all genera possess annulations in the anterior section, and with the re-classification of ''Yuyuannozoon'' each genus currently assigned to this family bears a lateral groove. Vetulicolids range in size from ''Beidazoon'' (around ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skeemella
''Skeemella'' is a genus of elongate animal from the Middle Cambrian Wheeler Shale and Marjum lagerstätte of Utah. It has been classified with the banffozoan vetulicolians. Description ''Skeemella'', which was first described in 2005, is diagnosed as having a body in two sections, covered in cuticle. The anterior section is short and wide, has a straight dorsal margin and a curving ventral margin, and is divided longitudinally in a way that makes it resemble a head shield. The anterior region is interpreted as being made of nine segments separated by thinner membranes (rather than as a single unit with multiple openings). ''Skeemella'' has a narrow, worm-shaped rear section with 43 segments in holotype specimen, identified as tergites separated by flexible membranes. The rear section terminates in what appears to be an arthropod telson, an elongate, unsegmented flattened structure that ends in two backward-pointing spines. In 2020, two more specimens of ''S. clavula'' were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heteromorphus
''Heteromorphus'' is an extinct genus of banffiid from the lower Cambrian Chengjiang lagerstatte. It contains one broadly accepted species, ''Heteromorphus confusus'', as well as a proposed junior synonym, ''Heteromorphus longicaudatus'' that may prove to be a separate species as additional specimens are examined. A much smaller species labeled "Form A" is allied with ''Heteromorphus'' at the class level but has not been formally described or assigned to ''Heteromorphus'' itself. Description Like ''Banffia'', ''Heteromorphus'' has a two-part body with a notable constriction between the parts, and a crossover that effectively reverses the dorsal and ventral sides between the anterior and posterior sections. The posterior portion is segmented, although the common presence of wrinkling makes counting the segments difficult. The anterior body shape ranges from torpedo-like to more rectangular, with a near-vertical anterior edge. ''Heteromorphus'' is separated from ''Banffia'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Banffia
''Banffia'' is a genus of animals described from Middle Cambrian fossils. The genus commemorates Banff, Alberta, near where the first fossil specimens were discovered. Its placement in higher taxa is controversial, with it mostly being considered to be a member of the enigmatic phylum Vetulicolia. Anatomy ''Banffia constricta'' is known from hundreds of fossils found in the Burgess Shales. It is up to 10 cm in length, and divided equally into anterior and posterior parts. The entire body is twisted in a clockwise spiral, as seen from the front. This is believed to be a secondary adaptation from an initial bilateral condition for a burrowing lifestyle. The anterior section is covered by two carapace-like un-mineralized shells that are fused together. A crown-like structure formed of three concentric circular features surrounds the mouth. An antenna-form structure just posterior to the mouth may be a sensory organ. The posterior section is composed of 40 to 50 segments. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
