Pseudoporambonites Zeng 1977

Pseudoporambonites ? sp. Pl. 28, Figs. 5–8 Material. Ten exfoliated specimens, including at least two dorsal and six ventral valves, from samples F4295, F4323, F4351, F4356, F4359, F4376, F4407 and F4426. The figured specimens are F4356, F4359 and F4426. Description. Shell large, inflated, biconvex...

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Main Authors: Hansen, Jesper, Holmer, Lars E.
Format: Text
Language:unknown
Published: Zenodo 2011
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Online Access:https://dx.doi.org/10.5281/zenodo.5243762
https://zenodo.org/record/5243762
id ftdatacite:10.5281/zenodo.5243762
record_format openpolar
institution Open Polar
collection DataCite Metadata Store (German National Library of Science and Technology)
op_collection_id ftdatacite
language unknown
topic Biodiversity
Taxonomy
Animalia
Brachiopoda
Rhynchonellata
Pentamerida
Tetralobulidae
Pseudoporambonites
spellingShingle Biodiversity
Taxonomy
Animalia
Brachiopoda
Rhynchonellata
Pentamerida
Tetralobulidae
Pseudoporambonites
Hansen, Jesper
Holmer, Lars E.
Pseudoporambonites Zeng 1977
topic_facet Biodiversity
Taxonomy
Animalia
Brachiopoda
Rhynchonellata
Pentamerida
Tetralobulidae
Pseudoporambonites
description Pseudoporambonites ? sp. Pl. 28, Figs. 5–8 Material. Ten exfoliated specimens, including at least two dorsal and six ventral valves, from samples F4295, F4323, F4351, F4356, F4359, F4376, F4407 and F4426. The figured specimens are F4356, F4359 and F4426. Description. Shell large, inflated, biconvex with maximum thickness at mid-length. Valves moderately thickwalled. Outline transversely subangular to subcircular with maximum width at 35–50% of valve length. Hinge-line straight, 85% as long as maximum valve width. L/W ratio 0.72–0.88. Largest specimen (a ventral valve) 19.9 mm long and 22.6 mm wide. Cardinal extremities obtuse. Commissure rectimarginate or slightly uniplicate. Shell impunctate. Multicostellate ornamentation of weak and rather dense equicostellae. Costellae 4–6 per mm, impressed on distal 12–20% of valve floor. Dorsal interarea short. Ventral sulcus narrow and weak, not always developed, but otherwise beginning well anterior of umbo, sometimes disappearing distally. Ventral interarea slightly concave and apsacline, 85% as wide as total valve width. Median ridge or septum extending from muscle field to about 45% of valve length. Muscle scars bounded by ridge, reaching 36% of valve length. Two lateral ridges or septa forming a lyre-shaped configuration on proximal part of valve floor. Mantle canal system saccate, moderately impressed, with gonadal sacs reaching anterior of mid-valve length. Remarks. The Spitsbergen specimens resemble the type species, Pseudoporambonites yichangensis Zeng, 1977, but differ in having denser costellae (normally 5 per mm compared to the 3 per mm of the type species); a more angular outline with a broader posterior margin; a markedly less plicate anterior margin; and smaller shells. The Chinese Dapingian P. hupeihensis (Wang, 1955) is elongate and strongly dorsibiconvex. Two additional species from SW China are here assigned to this genus: the Floian “ Punctolira ” resupinata Xu et al ., 1974 and the Dapingian “ Punctolira ” magna Xu et al ., 1974. “ Punctolira ” resupinata has about 2–3 costellae per mm, nearly straight lateral ventral ridges, and a rather poorly impressed mantle canal system. “ Punctolira ” magna has an L/W ratio of about 1.0–1.1, about 2–3 costellae per mm, and a median ventral septum reaching about mid-valve length. Currently, the Spitsbergen specimens are the oldest specimens referred to the genus from outside China. Poulsen (1927) described some specimens under open nomenclature from the Floian Nunatami Formation of northwestern Greenland that appear to belong to the same genus. Compared to the Spitsbergen specimens, they have much more strongly impressed ventral gonadal sacs and central and lateral ridges that extend into the anterior half of the ventral valve floor. Occurrence. Middle and upper parts of Nordporten Member, Kirtonryggen Formation, Basissletta in northeastern Ny Friesland, Spitsbergen. Plate 28 Palaeostrophia ? sp. Kirtonryggen Formation, Spora Member. Coll. G. Vallance & R. Fortey, 1967. 1. F5745, dorsal valve exterior. Sample F5745. 2. F5709, ventral valve exterior. Sample F5709. 3. F5708, ventral valve exterior. Sample F5708. 4. F5738, ventral valve exterior. Sample F5738. Pseudoporambonites ? sp. Kirtonryggen Formation, Nordporten Member. Coll. G. Vallance & R. Fortey, 1967. 5. F4426, dorsal valve exterior. Middle part of member. Sample F4426. 6. F4359, exfoliated ventral valve exterior with visible mantle canal system. Upper part of member. Sample F4359. 7–8. F4356, exfoliated ventral valve exterior and detail of partly exfoliated ornamentation. Upper part of member. Sample F4356. Porambonitoid? indet. Valhallfonna Formation, Profilbekken Member. 9–10. TSGF16770, detail of ornamentation and whole fragment of ventral valve exterior. 83 m above base. Coll. J. Hansen, 01.08.2008, sample JH-161. Camerella sp. Valhallfonna Formation, Profilbekken Member. 11. TSGF16772, ventral valve exterior. 63 m above base. Coll. J. Hansen, 24.07.2008, sample JH-90. Idiostrophia valdari Ross, 1972 Valhallfonna Formation, Olenidsletta Member. 12. TSGF16773, valve exterior. Coll. J. Hansen, 17.07.2008, sample JH-188. : Published as part of Hansen, Jesper & Holmer, Lars E., 2011, Taxonomy and biostratigraphy of Ordovician brachiopods from northeastern Ny Friesland, Spitsbergen 3076, pp. 1-122 in Zootaxa 3076 (1) on pages 109-111, DOI: 10.11646/zootaxa.3076.1.1, http://zenodo.org/record/5243500 : {"references": ["Zeng, Q. (1977) Brachiopoda. In: Hubei Institute of Geological Sciences et al. (Eds.), Palaeontological Atlas of central-south China, Early Palaeozoic Part. Earth Sciences Publishing House, Beijing, pp. 31 - 69. pls. 10 - 23. [in Chinese].", "Wang, Y. (1955) New genera of brachiopods. Acta Palaeontologica Sinica, 3 (2), 83 - 114, 6 pls. [in Chinese].", "Xu, H. - K., Rong, J. - Y. & Liu, D. - Y. (1974) Brachiopoda (Ordovician). In: Nanjing Institute of Geology and Palaeontology (Ed.), A Handbook of the stratigraphy and palaeontology in Southwest China. Science Press, Peking, pp. 144 - 154, pls. 64 - 66.", "Poulsen, C. (1927) The Cambrian, Ozarkian and Canadian faunas of Northwest Greenland. Meddelelser om Gronland, 70 (2), 233 - 343, pls. 14 - 21.", "Ross, R. J. Jr. (1972) Fossils from the Ordovician bioherm at Meiklejohn Peak, Nevada. U. S. Geological Survey Professional Paper, 685, 1 - 47, 18 pls."]}
format Text
author Hansen, Jesper
Holmer, Lars E.
author_facet Hansen, Jesper
Holmer, Lars E.
author_sort Hansen, Jesper
title Pseudoporambonites Zeng 1977
title_short Pseudoporambonites Zeng 1977
title_full Pseudoporambonites Zeng 1977
title_fullStr Pseudoporambonites Zeng 1977
title_full_unstemmed Pseudoporambonites Zeng 1977
title_sort pseudoporambonites zeng 1977
publisher Zenodo
publishDate 2011
url https://dx.doi.org/10.5281/zenodo.5243762
https://zenodo.org/record/5243762
long_lat ENVELOPE(70.203,70.203,-49.626,-49.626)
ENVELOPE(16.847,16.847,79.498,79.498)
ENVELOPE(17.220,17.220,69.504,69.504)
ENVELOPE(-62.833,-62.833,-64.983,-64.983)
ENVELOPE(17.566,17.566,79.743,79.743)
ENVELOPE(-66.000,-66.000,80.000,80.000)
ENVELOPE(-3.600,-3.600,-72.283,-72.283)
ENVELOPE(17.525,17.525,79.992,79.992)
geographic Greenland
Gronland
Ny Friesland
Spora
Median Ridge
Valhallfonna
Nunatami
Basissletta
Nordporten
geographic_facet Greenland
Gronland
Ny Friesland
Spora
Median Ridge
Valhallfonna
Nunatami
Basissletta
Nordporten
genre Greenland
Ny Friesland
Spitsbergen
genre_facet Greenland
Ny Friesland
Spitsbergen
op_relation http://zenodo.org/record/5243500
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op_rights Open Access
info:eu-repo/semantics/openAccess
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spelling ftdatacite:10.5281/zenodo.5243762 2023-05-15T16:30:38+02:00 Pseudoporambonites Zeng 1977 Hansen, Jesper Holmer, Lars E. 2011 https://dx.doi.org/10.5281/zenodo.5243762 https://zenodo.org/record/5243762 unknown Zenodo http://zenodo.org/record/5243500 http://publication.plazi.org/id/5444FFF3FFF6FFFB0B3FFFF1F866FF98 https://zenodo.org/communities/biosyslit https://dx.doi.org/10.11646/zootaxa.3076.1.1 http://zenodo.org/record/5243500 http://publication.plazi.org/id/5444FFF3FFF6FFFB0B3FFFF1F866FF98 https://dx.doi.org/10.5281/zenodo.5243763 https://zenodo.org/communities/biosyslit Open Access info:eu-repo/semantics/openAccess Biodiversity Taxonomy Animalia Brachiopoda Rhynchonellata Pentamerida Tetralobulidae Pseudoporambonites Text Taxonomic treatment article-journal ScholarlyArticle 2011 ftdatacite https://doi.org/10.5281/zenodo.5243762 https://doi.org/10.11646/zootaxa.3076.1.1 https://doi.org/10.5281/zenodo.5243763 2021-11-05T12:55:41Z Pseudoporambonites ? sp. Pl. 28, Figs. 5–8 Material. Ten exfoliated specimens, including at least two dorsal and six ventral valves, from samples F4295, F4323, F4351, F4356, F4359, F4376, F4407 and F4426. The figured specimens are F4356, F4359 and F4426. Description. Shell large, inflated, biconvex with maximum thickness at mid-length. Valves moderately thickwalled. Outline transversely subangular to subcircular with maximum width at 35–50% of valve length. Hinge-line straight, 85% as long as maximum valve width. L/W ratio 0.72–0.88. Largest specimen (a ventral valve) 19.9 mm long and 22.6 mm wide. Cardinal extremities obtuse. Commissure rectimarginate or slightly uniplicate. Shell impunctate. Multicostellate ornamentation of weak and rather dense equicostellae. Costellae 4–6 per mm, impressed on distal 12–20% of valve floor. Dorsal interarea short. Ventral sulcus narrow and weak, not always developed, but otherwise beginning well anterior of umbo, sometimes disappearing distally. Ventral interarea slightly concave and apsacline, 85% as wide as total valve width. Median ridge or septum extending from muscle field to about 45% of valve length. Muscle scars bounded by ridge, reaching 36% of valve length. Two lateral ridges or septa forming a lyre-shaped configuration on proximal part of valve floor. Mantle canal system saccate, moderately impressed, with gonadal sacs reaching anterior of mid-valve length. Remarks. The Spitsbergen specimens resemble the type species, Pseudoporambonites yichangensis Zeng, 1977, but differ in having denser costellae (normally 5 per mm compared to the 3 per mm of the type species); a more angular outline with a broader posterior margin; a markedly less plicate anterior margin; and smaller shells. The Chinese Dapingian P. hupeihensis (Wang, 1955) is elongate and strongly dorsibiconvex. Two additional species from SW China are here assigned to this genus: the Floian “ Punctolira ” resupinata Xu et al ., 1974 and the Dapingian “ Punctolira ” magna Xu et al ., 1974. “ Punctolira ” resupinata has about 2–3 costellae per mm, nearly straight lateral ventral ridges, and a rather poorly impressed mantle canal system. “ Punctolira ” magna has an L/W ratio of about 1.0–1.1, about 2–3 costellae per mm, and a median ventral septum reaching about mid-valve length. Currently, the Spitsbergen specimens are the oldest specimens referred to the genus from outside China. Poulsen (1927) described some specimens under open nomenclature from the Floian Nunatami Formation of northwestern Greenland that appear to belong to the same genus. Compared to the Spitsbergen specimens, they have much more strongly impressed ventral gonadal sacs and central and lateral ridges that extend into the anterior half of the ventral valve floor. Occurrence. Middle and upper parts of Nordporten Member, Kirtonryggen Formation, Basissletta in northeastern Ny Friesland, Spitsbergen. Plate 28 Palaeostrophia ? sp. Kirtonryggen Formation, Spora Member. Coll. G. Vallance & R. Fortey, 1967. 1. F5745, dorsal valve exterior. Sample F5745. 2. F5709, ventral valve exterior. Sample F5709. 3. F5708, ventral valve exterior. Sample F5708. 4. F5738, ventral valve exterior. Sample F5738. Pseudoporambonites ? sp. Kirtonryggen Formation, Nordporten Member. Coll. G. Vallance & R. Fortey, 1967. 5. F4426, dorsal valve exterior. Middle part of member. Sample F4426. 6. F4359, exfoliated ventral valve exterior with visible mantle canal system. Upper part of member. Sample F4359. 7–8. F4356, exfoliated ventral valve exterior and detail of partly exfoliated ornamentation. Upper part of member. Sample F4356. Porambonitoid? indet. Valhallfonna Formation, Profilbekken Member. 9–10. TSGF16770, detail of ornamentation and whole fragment of ventral valve exterior. 83 m above base. Coll. J. Hansen, 01.08.2008, sample JH-161. Camerella sp. Valhallfonna Formation, Profilbekken Member. 11. TSGF16772, ventral valve exterior. 63 m above base. Coll. J. Hansen, 24.07.2008, sample JH-90. Idiostrophia valdari Ross, 1972 Valhallfonna Formation, Olenidsletta Member. 12. TSGF16773, valve exterior. Coll. J. Hansen, 17.07.2008, sample JH-188. : Published as part of Hansen, Jesper & Holmer, Lars E., 2011, Taxonomy and biostratigraphy of Ordovician brachiopods from northeastern Ny Friesland, Spitsbergen 3076, pp. 1-122 in Zootaxa 3076 (1) on pages 109-111, DOI: 10.11646/zootaxa.3076.1.1, http://zenodo.org/record/5243500 : {"references": ["Zeng, Q. (1977) Brachiopoda. In: Hubei Institute of Geological Sciences et al. (Eds.), Palaeontological Atlas of central-south China, Early Palaeozoic Part. Earth Sciences Publishing House, Beijing, pp. 31 - 69. pls. 10 - 23. [in Chinese].", "Wang, Y. (1955) New genera of brachiopods. Acta Palaeontologica Sinica, 3 (2), 83 - 114, 6 pls. [in Chinese].", "Xu, H. - K., Rong, J. - Y. & Liu, D. - Y. (1974) Brachiopoda (Ordovician). In: Nanjing Institute of Geology and Palaeontology (Ed.), A Handbook of the stratigraphy and palaeontology in Southwest China. Science Press, Peking, pp. 144 - 154, pls. 64 - 66.", "Poulsen, C. (1927) The Cambrian, Ozarkian and Canadian faunas of Northwest Greenland. Meddelelser om Gronland, 70 (2), 233 - 343, pls. 14 - 21.", "Ross, R. J. Jr. (1972) Fossils from the Ordovician bioherm at Meiklejohn Peak, Nevada. U. S. Geological Survey Professional Paper, 685, 1 - 47, 18 pls."]} Text Greenland Ny Friesland Spitsbergen DataCite Metadata Store (German National Library of Science and Technology) Greenland Gronland ENVELOPE(70.203,70.203,-49.626,-49.626) Ny Friesland ENVELOPE(16.847,16.847,79.498,79.498) Spora ENVELOPE(17.220,17.220,69.504,69.504) Median Ridge ENVELOPE(-62.833,-62.833,-64.983,-64.983) Valhallfonna ENVELOPE(17.566,17.566,79.743,79.743) Nunatami ENVELOPE(-66.000,-66.000,80.000,80.000) Basissletta ENVELOPE(-3.600,-3.600,-72.283,-72.283) Nordporten ENVELOPE(17.525,17.525,79.992,79.992)