Labechiida
Labechiida Temporal range:
Possible reports as young as the Triassic | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Porifera |
Class: | †Stromatoporoidea |
Order: | †Labechiida Kühn, 1927 |
Labechiida is an extinct
Labechiids can be differentiated from other stromatoporoids by having an internal structure emphasizing cysts (pockets roofed by flat or convex cyst plates) and pillars (solid rods perpendicular to the surface).[2][5][6] The pillars may extend all the way to the surface and project out a short distance as small bumps known as papillae. Cyst plates may bear denticles (pointed thorns) or crenulations (pinched deflections) pointing upwards within the skeleton. Laminae (regular horizontal plates) are comparatively difficult to distinguish due to the more unorganized internal structure of labechiids compared to other stromatoporoids.
Taxonomy
From The Treatise on Invertebrate Paleontology (Part E, Revised):[2]
- Family Aulaceratidae Kühn, 1927
- Alleynodictyon Webby, 1971 [Upper Ordovician (Katian)]
- Aulacera Plummer, 1843 [Middle Ordovician (Darriwilian) – Upper Ordovician (Hirnantian)]
- Cryptophragmus Raymond, 1914 [Upper Ordovician (Sandbian – Katian)]
- Ludictyon Ozaki, 1938 [Middle Ordovician (Darriwilian) – early Silurian]
- Pararosenella Vassilyuk & Bogoyavlenskaya, 1982 [Upper Devonian (Famennian)]
- Quasiaulacera Copper, Stock, & Jin, 2013 [Upper Ordovician (Hirnantian)]
- Sinabeatricea Jeon et al., 2022 [Upper Ordovician (Katian)][7]
- Sinodictyon Yabe & Sugiyama, 1930 [Middle Ordovician (Darriwilian)]
- Thamnobeatricea Raymond, 1931 [Middle Ordovician (Darriwilian) – Upper Ordovician (Katian)]
- Family Labechiidae Nicholson, 1879
- Labechia Edwards & Haime, 1851 [Middle Ordovician (Darriwilian) – Upper Devonian (Famennian), Viséan?[3]]
- Labechiella Yabe & Sugiyama, 1930 [Middle Ordovician (Darriwilian) – Upper Devonian]
- Stratodictyon Webby, 1969 [Upper Ordovician (Sandbian – Katian)]
- Family Lophiostromatidae Nestor, 1966
- Dermatostroma Parks, 1910 [Upper Ordovician (Sandbian? – Katian)]
- Lophiostroma Nicholson, 1891 [Middle Ordovician (Darriwilian) – Upper Devonian (Frasnian), Triassic?]
- Tarphystroma? Nestor, Copper, & Stock, 2010 [early Silurian (Llandovery)]
- Family Platiferostromatidae Khalfina & Yavorsky, 1973
- Cystocerium Nestor, 1967 [mid-Silurian (Wenlock)]
- Parastylostroma Bogoyavlenskaya, 1982 [Upper Devonian (Famennian)]
- Platiferostroma Khalfina & Yavorsky, 1973 [Upper Devonian (Famennian)]
- Pleostylostroma Wang, 1982 [early Silurian (Llandovery)]
- Stromatodictyon? Khalfina, 1972 [early – mid Silurian (Llandovery – Wenlock)]
- Vietnamostroma Nguyen Huu Hung & Mistiaen, 1998 [Upper Devonian (Famennian)]
- Family Rosenellidae Khalfina & Yavorsky, 1973
- Cystostroma Galloway & St. Jean, 1957 [Lower Ordovician (Floian)[1] – Upper Devonian]
- Forolinia Nestor, 1964 [early Silurian]
- Priscastroma Khromykh, 1999 [Middle Ordovician (Darriwilian)]
- Pseudostylodictyon Ozaki, 1938 [Middle Ordovician (Darriwilian) – late Silurian]
- Rosenella Nicholson, 1886 [Middle Ordovician (Darriwilian) – Upper Devonian (Famennian)]
- Rosenellinella Yavorsky, 1967 [early – mid Silurian]
- Family Stromatoceriidae Bogoyavlenskaya, 1969
- Cystistroma Etheridge, 1895 [Upper Ordovician (Sandbian – Katian)]
- Radiostroma Webby, 1979 [Upper Ordovician (Katian)]
- Stromatocerium Hall, 1847 [Upper Ordovician (Sandbian – Katian)]
- Family Stylostromatidae Webby, 1993
- Eopennastroma Wang, 1978 [Upper Devonian (Famennian)]
- Pachystylostroma Nestor, 1964 [Middle Ordovician (Darriwilian) – Upper Devonian]
- Pennastroma Dong, 1964 [Upper Devonian (Famennian)]
- Spinostroma Wang, 1978 [Upper Devonian (Famennian)]
- Stylostroma Gorsky, 1938 [Upper Ordovician (Katian) – Upper Devonian]
Evolution
Ordovician
The earliest reported labechiid species is
In the Sandbian stage of the Late Ordovician, labechiids spread to regions equivalent to Scotland and Australia, and some former Chinese endemics (such as the tree-shaped aulaceratids) populated Laurentia (North America) for the first time.[4] During the Katian stage, labechiids reached their maximum diversity and were abundant in tropical reef ecosystems worldwide. They were significantly less common in temperate areas corresponding to Central Asia.[4] Most Late Ordovician labechiid genera were cosmopolitan, while endemics were few. Global cooling in the first pulse of the Late Ordovician mass extinction (~445 Ma) led to the extinction of the short-lived family Stromatoceriidae, and Hirnantian-age stromatoporoid fossils are limited to only a few localities in Canada and Northern Europe.[4] Only two labechiids (Aulacera and Pachystylostroma) retain any semblance of commonness during the extinction interval.[4]
Silurian
Labechiids which survived into the Llandovery Epoch (early Silurian) were inconspicuous relative to other diversifying stromatoporoid orders such as clathrodictyids and actinostromatids. South China and Siberia were notable exceptions where labechiids temporarily remained the most diverse group of stromatoporoids.[4] Even as stromatoporoids collectively reached their maximum Silurian diversity in the Wenlock Epoch (middle Silurian), labechiids were not among the beneficiaries.[4] Labechiids were still rare in the Ludlow and Pridoli epochs (late Silurian), though the typical Ordovician genus Lophiostroma made an unexpected recovery in Baltica (Eastern Europe) and Turkey.[4]
Devonian
No unambiguously new labechiid genera evolved through the entire
Unlike other stromatoporoids, labechiids were not adversely affected by the
Despite being reinvigorated after the Kellwasser event, labechiids and their reef ecosystems would not survive the Hangenberg event (~359 Ma), a second mass extinction which marked the end of the Famennian stage and Devonian period.[10] This extinction is generally considered absolute, but possible exceptions have been reported to imply post-Devonian survival: Labechia carbonaria (from the Viséan stage of Carboniferous England)[3] and Lophiostroma boletiformis (from Triassic rocks of the Pamir Mountains).[2] These discontinuous reports pose the same set of questions applied to Early and Middle Devonian occurrences.[11]
References
- ^ ISSN 1598-7477.
- ^ ISBN 978-0-9903621-2-8.
- ^ ISSN 2524-4507.
- ^ ISBN 978-0-9903621-2-8.
- ISBN 978-0-9903621-2-8.
- ^ Stearn, Colin W.; Webby, Barry D.; Nestor, Heldur; Stock, Carl W. (1999). "Revised classification and terminology of Palaeozoic stromatoporoids" (PDF). Acta Palaeontologica Polonica. 44 (1): 1–70.
- ISSN 0022-3360.
- ^ ISBN 978-0-9903621-2-8.
- ISSN 1068-7971.
- ^ ISBN 978-0-9903621-2-8.
- ^ ISBN 978-0-9903621-2-8.