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Vetulicolida
Vetulicolida is a class of vetulicolians. It consists of the order Vetulicolata (which contains the families Vetulicolidae and Didazoonidae) and the genus '' Nesonektris'', which is of uncertain placement. It is distinguished from the Banffozoa by the number and size of posterior segments as well as features of the anterior section. Description The Vetulicolidans anterior body appears to consist of fused segments, with five gill pouches at the intersections of the segment boundaries and a lateral groove that does not reach the posterior edge. The posterior section is clearly segmented with relatively wide segments comparred to banffozoans such as ''Banffia'' or '' Heteromorphus''. Taxonomy In 1997, Chen and Zhou defined Vetulicolida as a class to contain '' Vetulicola'' and '' Banffia''. Hou and Bergström also defined Vetulicolida that same year, but as an order containing the new family Vetulicolidae. The name Vetulicolida was used at either or both ranks until 2007, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vetulicolata
Vetulicolida is a class of vetulicolians. It consists of the order Vetulicolata (which contains the families Vetulicolidae and Didazoonidae) and the genus ''Nesonektris'', which is of uncertain placement. It is distinguished from the Banffozoa by the number and size of posterior segments as well as features of the anterior section. Description The Vetulicolidans anterior body appears to consist of fused segments, with five gill pouches at the intersections of the segment boundaries and a lateral groove that does not reach the posterior edge. The posterior section is clearly segmented with relatively wide segments comparred to banffozoans such as ''Banffia'' or ''Heteromorphus''. Taxonomy In 1997, Chen and Zhou defined Vetulicolida as a class to contain ''Vetulicola'' and ''Banffia''. Hou and Bergström also defined Vetulicolida that same year, but as an order containing the new family Vetulicolidae. The name Vetulicolida was used at either or both ranks until 2007, when a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vetulicolians
Vetulicolia is a group of bilaterian marine animals encompassing several extinct species from the Cambrian, and possibly Ediacaran, periods. As of 2023, the majority of workers favor placing Vetulicolians in the stem group of the Chordata, but some continue to favor a more crownward placement as a sister group to the Tunicata. It was initially erected as a monophyletic clade with the rank of phylum in 2001, with subsequent work supporting its monophyly. However, more recent research suggests that vetulicolians may be paraphyletic and form a basal evolutionary grade of stem chordates. Etymology The taxon name, Vetulicolia, is derived from the type genus, ''Vetulicola'', which is a compound Latin word composed of ''vetuli'' "old" and ''cola'' "inhabitant". It was named after ''Vetulicola cuneata'', the first species of the group described in 1987. Description The vetulicolian body plan comprises two parts: a voluminous rostral (anterior) forebody, tipped with an anteriorly ... [...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] |
Banffozoa
Banffozoa (also called Heteromorphida) 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 (which has only one family, Banffiidae) 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 (if it is a banffozoan or vetulicolian at all). Banffozoa may be paraphyletic even if Vetulicolia is monophyletic. Description Banffozoans have a bipartite body with a smooth anterior part that generally lacks evidence of segmentation and may or may not have a lateral groove. The posterior section features far more segments than the Vetulicolida, and (except in ''Skeemella'') these segments are each much narrower as well. Lateral pouches such as those found in the Vetulicolida have not been seen, although s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nesonektris
''Nesonektris aldridgei'' is an extinct vetulicolian from the Late Botomian-aged Emu Bay Shale Lagerstätte in Kangaroo Island, Australia. So far, it is the fourth described vetulicolian that is not restricted to the Maotianshan Shales (the other three being '' Ooedigera'' of Sirius Passet, '' Banffia'' of the Burgess Shale, and '' Skeemella'' of the Pierson Cove Formation above the Wheeler Shale). Description ''N. aldridgei'' is known from several incomplete fossils which suggest that, in life, it was a fairly large animal (when compared to other vetulicolians). The largest fossil is about 150 millimetres ( 5.9 inches) long, leading researchers to estimate that that individual was about 170 millimetres (6.7 inches) long. The exquisitely preserved fossils show that running the length inside the tail was a notochord, thereby demonstrating the animal's chordate affinities as being related to tunicates. The forebody, and overall form are similar to vetulicolids of Vetulicol ... [...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] |
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] |
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] |
Yuyuanozoon
''Yuyuanozoon magnificissimi'', from the Cambrian Stage 3 Chengjiang lagerstatte, is the largest known vetulicolian, an extinct species of marine animal, with specimens up to 20 cm in length compared to 5–14 cm for other vetulicolian species. Etymology The generic name translates as "Animal of Yu Yuan," Yu Yuan being an ancient name for Chengjiang County. The specific name, ''magnificissimi'', translates as "of the most magnificent one," in reference to the great size of the holotype. Description Its body is non-biomineralized and consists of an elongate ovoid anterior section, with a segmented posterior section roughly one-third of the width and half the length of the anterior. The anterior opening is wide, with a narrow, raised circumventing rim 5 mm posterior to the opening. The anterior section is divided into six subdivisions by five circumventing lines, with gill openings placed symmetrically on each side, coinciding with the lines. In the holotype, gill filaments a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Didazoonidae
Didazoonidae is a vetulicolian family within the 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 Didazoonidae after additional speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
