Laminacaris

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Laminacaris chimera
Temporal range: Cambrian Stage 3
20191221 Radiodonta frontal appendage Laminacaris chimera.png
Frontal appendage
Laminacaris chimera CJHMD-00003.png
Fossil of L. chimera
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Dinocaridida
Order: Radiodonta
Genus: Laminacaris
Guo et al., 2018
Species:
L. chimera
Binomial name
Laminacaris chimera
Guo et al., 2018

Laminacaris is a genus of extinct stem-group arthropods (Radiodonta) that lived during the Cambrian period. It is monotypic with a single species Laminacaris chimera, the fossil of which was described from the Chengjiang biota of China in 2018. [1] Around the same time, two specimens that were similar or of the same species were discovered at the Kinzers Formation in Pennsylvania, USA. [2] The first specimens from China were three frontal appendages, without the other body parts.

Contents

Discovery and naming

Laminacaris specimens were discovered from the mudstones of the Yu'anshan Member of the Chiungchussu Formation in eastern Yunnan Province, the Mafang section in the Haikou area at Kunming, and the Fengkoushao section , Chengjiang. The name is derived from Latin words, lamina meaning thin blade, and caris for crab; the species name refers to a Greek mythological creature, Chimera, that has a body composed of parts of more than one animal. [1]

Description

Laminacaris size diagram 20210215 Laminacaris size.png
Laminacaris size diagram

The large frontal appendage is the most prominent and distinctive feature in Cambrian arthropods. [3] [4] The largest frontal appendage of Laminacaris (YKLP 13338) is around 28 cm (11 in) long, which would have belonged to an individual between 53.2–78.4 cm (20.9–30.9 in) long, based on proportion of Innovatiocaris (which is once treated as "Anomalocaris" saron ). [5] In many radiodonts and anomalocarids, the appendage is divided into segments called podomeres. Laminacaris's appendage has 15 podomeres, including 2 podomeres (podomeres 1 and 2) in the shaft and 13 (podomeres 3–15) in the distal articulated region. [1] The appendage bears several spines called endites on each lobomere. The biggest endite called shaft endite at the base (towards the body) is small and straight in most Cambrian arthropods, but is large, recurved and bears auxiliary spines in Laminacaris, Anomalocaris briggsi and Pahvantia hastata. [6]

Classification

A discovery of Burgess Shale radiodont Cambroraster falcatus in 2019 that was classified as member of the family Hurdiidae, led to the justification that Laminacaris could be the closest relative of and sister to Hurdiidae among the Radiodonta. Laminacaris may be a transitional form that diverged from the common ancestors. [7] Phylogenetic analysis based on the discovery of Pahvantia hastata, another member of Hurdiidae, shows that Laminacaris falls within the members of the family Anomalocarididae, next to Anomalocaris . [5] In 2022, it is treated that is possibly related to Innovatiocaris and Guanshancaris . [8] In 2023, its taxonomic position was recovered as Radiodonta incertae sedis. [9]

Related Research Articles

<span class="mw-page-title-main">Dinocaridida</span> Extinct class of basal arthropods

Dinocaridida is a proposed fossil taxon of basal arthropods, which flourished during the Cambrian period and survived up to Early Devonian. Characterized by a pair of frontal appendages and series of body flaps, the name of Dinocaridids refers to the suggested role of some of these members as the largest marine predators of their time. Dinocaridids are occasionally referred to as the 'AOPK group' by some literatures, as the group compose of Radiodonta, Opabiniidae, and the "gilled lobopodians" Pambdelurion and Kerygmachelidae. It is most likely paraphyletic, with Kerygmachelidae and Pambdelurion more basal than the clade compose of Opabiniidae, Radiodonta and other arthropods.

<i>Anomalocaris</i> Extinct genus of cambrian radiodont

Anomalocaris is an extinct genus of radiodont, an order of early-diverging stem-group arthropods.

<i>Peytoia</i> Extinct genus of radiodont

Peytoia is a genus of hurdiid radiodont, an early diverging order of stem-group arthropods, that lived in the Cambrian period, containing two species, Peytoia nathorsti from the Miaolingian of Canada and Peytoia infercambriensis from Poland, dating to Cambrian Stage 3. Its two frontal appendages had long bristle-like spines, it had no fan tail, and its short stalked eyes were behind its large head.

<span class="mw-page-title-main">Anomalocarididae</span> Clade of extinct arthropods

Anomalocarididae is an extinct family of Cambrian radiodonts, a group of stem-group arthropods.

<i>Peytoia infercambriensis</i> Extinct species of arthropod

Peytoia infercambriensis is a species of hurdiid radiodont in the genus Peytoia.

<i>Schinderhannes bartelsi</i> Extinct species of radiodont

Schinderhannes bartelsi is a species of hurdiid radiodont (anomalocaridid), known from one specimen from the Lower Devonian Hunsrück Slates. Its discovery was astonishing because the latest definitive radiodonts were known only from the Early Ordovician, at least 66 million years earlier than this taxon.

<span class="mw-page-title-main">Radiodonta</span> Extinct order of basal arthropods

Radiodonta is an extinct order of stem-group arthropods that was successful worldwide during the Cambrian period. They may be referred to as radiodonts, radiodontans, radiodontids, anomalocarids, or anomalocaridids, although the last two originally refer to the family Anomalocarididae, which previously included all species of this order but is now restricted to only a few species. Radiodonts are distinguished by their distinctive frontal appendages, which are morphologically diverse and used for a variety of functions. Radiodonts included the earliest large predators known, but they also included sediment sifters and filter feeders. Some of the most famous species of radiodonts are the Cambrian taxa Anomalocaris canadensis, Hurdia victoria, Peytoia nathorsti, Titanokorys gainessii, Cambroraster falcatus and Amplectobelua symbrachiata. The later surviving members include the subfamily Aegirocassisinae from the Early Ordovician of Morocco and the Early Devonian member Schinderhannes bartelsi from Germany.

<i>Hurdia</i> Extinct genus of radiodonts

Hurdia is an extinct genus of hurdiid radiodont that lived 505 million years ago during the Cambrian Period. Fossils have been found in North America, China and the Czech Republic.

<i>Stanleycaris</i> Extinct genus of basal hurdiid radiodonts

Stanleycaris is an extinct, monotypic genus of hurdiid radiodont from the middle Cambrian (Miaolingian). The type species is Stanleycaris hirpex. Stanleycaris was described from the Stephen Formation near the Stanley Glacier and Burgess Shale locality of Canada, as well as Wheeler Formation of United States. The genus was characterized by the rake-like frontal appendages with robust inner spines.

<i>Caryosyntrips</i> Extinct genus of arthropod

Caryosyntrips ("nutcracker") is an extinct genus of stem-arthropod which known from Canada, United States and Spain during the middle Cambrian.

<span class="mw-page-title-main">Amplectobeluidae</span> Extinct clade of Cambrian organisms

Amplectobeluidae is a clade of Cambrian radiodonts. It currently includes five definitive genera, Amplectobelua, Lyrarapax, Ramskoeldia, Guanshancaris and a currently unnamed genus from the lower Cambrian aged Sirius Passet site in Greenland. There is also a potential fifth genus, Houcaris, but that genus has become problematic in terms of its taxonomic placement.

<i>Aegirocassis</i> Extinct genus of radiodonts

Aegirocassis is an extinct genus of giant radiodont arthropod belonging to the family Hurdiidae that lived 480 million years ago during the early Ordovician in the Fezouata Formation of Morocco. It is known by a single species, Aegirocassis benmoulai. Van Roy initiated scientific study of the fossil, the earliest known of a "giant" filter-feeder discovered to date. Aegirocassis is considered to have evolved from early predatory radiodonts. This animal is characterized by its long, forward facing head sclerite, and the endites on its frontal appendages that bore copious amounts of baleen-like auxiliary spines. This animal evolving filter-feeding traits was most likely a result of the Great Ordovician Biodiversification Event, when environmental changes caused a diversification of plankton, which in turn allowed for the evolution of new suspension feeding lifeforms. Alongside the closely related Pseudoangustidontus, an unnamed hurdiid from Wales, the middle Ordovician dinocaridid Mieridduryn, and the Devonian hurdiid Schinderhannes this radiodont is one of the few dinocaridids known from post-Cambrian rocks.

<span class="mw-page-title-main">Hurdiidae</span> Extinct family of arthropods

Hurdiidae is an extinct cosmopolitan family of radiodonts, a group of stem-group arthropods, which lived during the Paleozoic Era. It is the most long-lived radiodont clade, lasting from the Cambrian period to the Devonian period.

<i>Ramskoeldia</i> Extinct genus of Amplectobeluid radiodont

Ramskoeldia is a genus of amplectobeluid radiodont described in 2018. It was the second genus of radiodont found to possess gnathobase-like structures and an atypical oral cone after Amplectobelua. The type species, Ramskoeldia platyacantha, was discovered in the Chengjiang biota of China, the home of numerous radiodontids such as Amplectobelua and Lyrarapax.

<i>Ursulinacaris</i> Extinct genus of hurdiid radiodonts

Ursulinacaris is a genus of hurdiid radiodont from the Cambrian of North America. It contains one known species, Ursulinacaris grallae. It was described in 2019, based on fossils of the frontal appendages discovered in the 1990s and thereafter. The endites of Ursulinacaris were very slender, unlike other hurdiids such as Peytoia or Hurdia. It was initially reported as the first hurdiid with paired endites, but Moysiuk & Caron (2021) suggested that it is actually the preservation of the fossils and thus no paired endites.

<i>Houcaris</i> Genus of radiodonts

Houcaris is a possibly paraphyletic radiodont genus, tentatively assigned to either Amplectobeluidae, Anomalocarididae or Tamisiocarididae, known from Cambrian Series 2 of China and the United States. The type species is Houcaris saron which was originally described as a species of the related genus Anomalocaris. Other possible species include H. magnabasis and H. consimilis. The genus Houcaris was established for the two species in 2021 and honors Hou Xianguang, who had discovered and named the type species Anomalocaris saron in 1995 along with his colleagues Jan Bergström and Per E. Ahlberg.

<i>Pahvantia</i> Extinct genus of radiodonts

Pahvantia is an extinct genus of hurdiid radiodont from the Cambrian. It is known by a single species, Pahvantia hastata, described from Wheeler Shale and Marjum Formation in Utah. Although it was once considered as filter feeder using large number of putative setae, this structures are later considered as misidentification of trunk materials.

Innovatiocaris is a genus of radiodont of uncertain family from the early Cambrian Chengjiang Lagerstätte of Yunnan Province, China. The genus contains two named species, I. maotianshanensis, known from a nearly complete young individual measuring up to 15.2 cm (6.0 in) and isolated frontal appendages, and I.? multispiniformis, known from a complete frontal appendage.

<i>Pseudoangustidontus</i> Hurdiid radiodont from the Early Ordovician

Pseudoangustidontus is a genus of hurdiid (peytoiid) radiodont from the Lower Ordovician of Morocco. This genus is known from two described species, P. duplospineus and P. izidigua, with some specimens that are hard to determine which species to belong to. This animal is only known from the Fezouata Formation, a fossil site in Morocco that is of Lagerstätte status, meaning that the fossils from this site are exceptionally preserved. Because of its partial remains, its classification was debated, but with more complete fossils it is identified as radiodont frontal appendage.

<i>Lenisicaris</i> Extinct genus of Cambrian radiodont

Lenisicaris is a Cambrian anomalocaridid radiodont, known from the Maotianshan Shales of China and the Kinzers Formation of Pennsylvania.

References

  1. 1 2 3 Guo, Jin; Pates, Stephen; Cong, Peiyun; Daley, Allison C.; Edgecombe, Gregory D.; Chen, Taimin; Hou, Xianguang (2019) [13 August 2018]. "A new radiodont (stem Euarthropoda) frontal appendage with a mosaic of characters from the Cambrian (Series 2 Stage 3) Chengjiang biota". Papers in Palaeontology. 5 (1): 99–110. doi: 10.1002/spp2.1231 . S2CID   134909330.
  2. Pates, Stephen; Daley, Allison C. (2019). "The Kinzers Formation (Pennsylvania, USA): the most diverse assemblage of Cambrian Stage 4 radiodonts". Geological Magazine. 156 (7): 1233–1246. Bibcode:2019GeoM..156.1233P. doi:10.1017/S0016756818000547. S2CID   134299859.
  3. Liu, Jianni; Dunlop, Jason A. (2014). "Cambrian lobopodians: A review of recent progress in our understanding of their morphology and evolution". Palaeogeography, Palaeoclimatology, Palaeoecology. 398: 4–15. Bibcode:2014PPP...398....4L. doi:10.1016/j.palaeo.2013.06.008.
  4. Giribet, Gonzalo; Edgecombe, Gregory D. (2019). "The Phylogeny and Evolutionary History of Arthropods". Current Biology. 29 (12): R592–R602. doi: 10.1016/j.cub.2019.04.057 . PMID   31211983. S2CID   189926344.
  5. 1 2 Lerosey-Aubril, Rudy; Pates, Stephen (2018). "New suspension-feeding radiodont suggests evolution of microplanktivory in Cambrian macronekton". Nature Communications. 9 (1): 3774. Bibcode:2018NatCo...9.3774L. doi:10.1038/s41467-018-06229-7. ISSN   2041-1723. PMC   6138677 . PMID   30218075. Dryad Data
  6. Pates, Stephen; Daley, Allison C.; Butterfield, Nicholas J. (2019). "First report of paired ventral endites in a hurdiid radiodont". Zoological Letters. 5 (1): 18. doi: 10.1186/s40851-019-0132-4 . PMC   6560863 . PMID   31210962.
  7. Moysiuk, J.; Caron, J.-B. (2019). "A new hurdiid radiodont from the Burgess Shale evinces the exploitation of Cambrian infaunal food sources". Proceedings of the Royal Society B: Biological Sciences. 286 (1908): 20191079. doi:10.1098/rspb.2019.1079. ISSN   1471-2954. PMC   6710600 . PMID   31362637.
  8. Zeng, Han; Zhao, Fangchen; Zhu, Maoyan (2022-09-07). "Innovatiocaris, a complete radiodont from the early Cambrian Chengjiang Lagerstätte and its implications for the phylogeny of Radiodonta". Journal of the Geological Society. 180. doi:10.1144/jgs2021-164. ISSN   0016-7649. S2CID   252147346.
  9. Potin, Gaëtan J.-M.; Daley, Allison C. (2023). "The significance of Anomalocaris and other Radiodonta for understanding paleoecology and evolution during the Cambrian explosion". Frontiers in Earth Science. 11. Bibcode:2023FrEaS..1160285P. doi: 10.3389/feart.2023.1160285 . ISSN   2296-6463.