Archaeopriapulida is a group of
priapulid-like worms known from
Cambrian
The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million ...
lagerstätte.
The group is closely related to, and very similar to, the modern Priapulids.
It is unclear whether it is mono- or polyphyletic.
Despite a remarkable morphological similarity to their modern cousins,
they fall outside of the priapulid
crown group
In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. ...
, which is not unambiguously represented in the fossil record until the Carboniferous.
They are probably closely related or paraphyletic to the
palaeoscolecid
The palaeoscolecids are a group of extinct ecdysozoan worms resembling armoured priapulids. They are known from the Lower Cambrian to the late Silurian; they are mainly found as disarticulated sclerites, but are also preserved in many of the Camb ...
s; the relationship between these basal worms is somewhat unresolved.
[
]
Species
* Genus '' Acosmia maotiania'' Chen & Zhoi 1997 (Chengjiang deposits)
** '' Acosmia maotiania'' Chen & Zhoi 1997
* Genus ''Archotuba
''Archotuba'' is a genus of elongated conical tubes that were seemingly deposited by colonial organisms. Known from the Chengjiang, its biological affinity is uncertain; it somewhat resembles the tubes of the ' priapulid' ''Selkirkia'', but a cn ...
'' Hou et al. 1999 (possibly a Cnidarian
Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, predominantly the latter.
Their distinguishing feature is cnidocytes, specialized cells that th ...
) (Chengjiang deposits)
** '' Archotuba conoidalis'' Hou et al. 1999
* Genus '' Baltiscalida'' Slater et al. 2017
** '' Baltiscalida njorda'' Slater et al. 2017
* Genus '' Eopriapulites'' Liu & al 2014
** '' Eopriapulites sphinx'' Liu & al 2014
* Genus ''Eximipriapulus
''Eximipriapulus'' is a genus of priapulid-like organisms, perhaps belonging to the crown group, known from the Chengjiang biota.
Paleoecology
Eximipriapulus is known to live inside Hyolith
Hyoliths are animals with small conical surface, ...
'' Ma et al. 2014 (Chengjiang deposits) Eximipriapulus globocaudatus
''Eximipriapulus'' is a genus of priapulid-like organisms, perhaps belonging to the crown group, known from the Chengjiang biota.
Paleoecology
Eximipriapulus is known to live inside Hyolith
Hyoliths are animals with small conical surface, ...
'' Ma et al. 2014
* Genus '' Lagenula'' Luo & Hu 1999 nomen dubium (Chengjiang deposits)Lecythioscopa
''Lecythioscopa'' is a genus of probable archaeopriapulid known from two specimens from the Walcott Quarry from the Middle Cambrian Burgess Shale.
Morphology
The specimens of ''Lectythioscopa'' are both missing their posterior portions, leavi ...
'' Conway Morris 1977 (Burgess Shale)
** '' Lecythioscopa simplex'' (Walcott 1931) Conway Morris 1977 'Canadia simplex'' Walcott 1931* Genus '' Oligonodus'' Luo & Hu 1999 nomen dubium (Chengjiang deposits)Omnidens amplus
''Omnidens amplus'', meaning "large all-tooth", is an extinct species of large Cambrian animal known only from a series of large mouth apparatus, originally mistaken as the mouthparts of anomalocaridids. When first named, it was interpreted as a ...
'' Hou & al 2006
* Genus '' Sandaokania'' Luo & Hu 1999 nomen dubium (Chengjiang deposits)Priapulites
The fossil taxon ''Priapulites'' is the earliest-known crown-group priapulid, and is closely related to the Priapulidae
Priapulidae is the canonical family of priapulid
Priapulida (priapulid worms, from Gr. πριάπος, ''priāpos'' 'Pri ...
'' Schram 1973 (Mazon Creek)
** '' Priapulites konecniorum'' Schram 1973
* Family Palaeopriapulitidae Hou et al. 1999
** Genus '' Sicyophorus'' Luo & Hu 1999 (Chengjiang deposits)Selkirkia
''Selkirkia'' is a genus of predatory, tubicolous priapulid worms known from the Middle Cambrian Burgess Shale, Ogygopsis Shale and Puncoviscana Formation. 142 specimens of ''Selkirkia'' are known from the Greater Phyllopod bed, where they compr ...
'' Walcott 1911
*** ''Selkirkia elongata
''Selkirkia'' is a genus of predatory, tubicolous priapulid worms known from the Middle Cambrian Burgess Shale, Ogygopsis Shale and Puncoviscana Formation. 142 specimens of ''Selkirkia'' are known from the Greater Phyllopod bed, where they compr ...
'' Luo & Hu 1999 (Chengjiang deposits)
*** ''Selkirkia columbia
''Selkirkia'' is a genus of predatory, tubicolous priapulid worms known from the Middle Cambrian Burgess Shale, Ogygopsis Shale and Puncoviscana Formation. 142 specimens of ''Selkirkia'' are known from the Greater Phyllopod bed, where they c ...
'' Walcott 1911 (Burgess Shale)
*** ''Selkirkia pennsylvanica
''Selkirkia'' is a genus of predatory, tubicolous priapulid worms known from the Middle Cambrian Burgess Shale, Ogygopsis Shale and Puncoviscana Formation. 142 specimens of ''Selkirkia'' are known from the Greater Phyllopod bed, where they c ...
'' Resser & Howell 1938
*** ''Selkirkia spencei
''Selkirkia'' is a genus of predatory, tubicolous priapulid worms known from the Middle Cambrian Burgess Shale, Ogygopsis Shale and Puncoviscana Formation. 142 specimens of ''Selkirkia'' are known from the Greater Phyllopod bed, where they c ...
'' Resser 1939
*** ''Selkirkia willoughbyi
''Selkirkia'' is a genus of predatory, tubicolous priapulid worms known from the Middle Cambrian Burgess Shale, Ogygopsis Shale and Puncoviscana Formation. 142 specimens of ''Selkirkia'' are known from the Greater Phyllopod bed, where they compr ...
'' Conway Morris & Robison 1986
* Order Ancalagonida Adrianov & Malakhov 1995 (stem Scalidophora)Fieldia lanceolata
''Fieldia'' may refer to a number of different genera in various scientific fields:
Botany
* ''Fieldia'' (plant) A. Cunningham, 1825, a genus of plants in the family Gesneriaceae. Fieldia is also used as a common name for '' Fieldia australis'', ...
'' Walcott 1912
** Genus ''Scolecofurca
''Scolecofurca'' is a genus of stem-group priapulid worm dating from the Middle Cambrian period approximately 505 million years ago.
It is known from a single fossil specimen from the Raymond Quarry in the Burgess Shale
The Burgess Shale ...
'' Conway Morris 1977 (Burgess Shale)
*** ''Scolecofurca rara
''Scolecofurca'' is a genus of stem-group priapulid worm dating from the Middle Cambrian period approximately 505 million years ago.
It is known from a single fossil specimen from the Raymond Quarry
Raymond is a male given name. It was bor ...
'' Conway Morris 1977
** Family Ottoiidae
''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 ...
Walcott 1911
*** Genus ''Ottoia
''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 ...
'' Walcott 1911
**** '' Ottoia cylindrica'' (Sun & Hou 1987)
**** '' Ottoia guizhouenis'' Yang, Zhao & Zhang 2016
**** '' Ottoia prolifica'' Walcott 1911 (Burgess Shale)
**** '' Ottoia tenuis'' Walcott 1911
**** '' Ottoia tricuspida'' Smith, Harvey & Butterfield 2015
** Family Corynetidae Huang, Vannier & Chen 2004
*** Genus ''Corynetis
''Corynetis'' is a genus of archaeopriapulid
Archaeopriapulida is a group of priapulid-like worms known from Cambrian lagerstätte. The group is closely related to, and very similar to, the modern Priapulids. It is unclear whether it is mono ...
'' Luo & Hu 1999
**** '' Corynetis brevis'' Luo & Hu 1999 ) (Chengjiang deposits)
**** ''Corynetis fortis">'Anningvermis multispinosus'' Huang et al 2004
) (Chengjiang deposits)
**** ''Corynetis fortis''
Hu et al. 2012 (Chengjiang deposits)
**** ''Corynetis pusillus''
(Klug 1842)
** Family Miskoiidae
Walcott 1911
*** Genus ''Louisella''
Conway Morris 1977 (Burgess Shale)
**** ''Louisella pedunculata''
(Walcott 1911) Conway Morris 1977
*** Genus ''
Miskoia
''Louisella'' is a genus of worm known from the Middle Cambrian Burgess Shale. It was originally described by Charles Walcott in 1911 as a holothurian echinoderm, and represents a senior synonym of ''Miskoia'', which was originally described as a ...
''
Walcott 1911
**** ''
Miskoia placida
''Louisella'' is a genus of worm known from the Middle Cambrian Burgess Shale. It was originally described by Charles Walcott in 1911 as a holothurian echinoderm, and represents a senior synonym of ''Miskoia'', which was originally described as ...
''
Walcott 1931
**** ''
Miskoia preciosa''
Walcott 1911
References
{{Taxonbar, from=Q4785523
Priapulida