Parapeytoia

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Parapeytoia
Temporal range: Cambrian Stage 3–Cambrian Stage 4
Parapeytoia yunnanensis NIGPAS 115334 (cropped).jpg
Holotype of Parapeytoia yunnanensis, part and counterpart
20191021 Parapeytoia yunnanensis ventral structures.png
Ventral structures of the same species
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Megacheira
Family: Jianfengiidae
Genus: Parapeytoia
Hou, Bergström & Ahlberg, 1995 [1]
Type species
Parapeytoia yunnanensis
Hou, Bergstrom & Ahlberg, 1995 [1]

Parapeytoia is a genus of Cambrian arthropod. The type and only described species is Parapeytoia yunnanensis, lived over 518 million years ago [2] (Cambrian Stage 3) in the Maotianshan shales of Yunnan, China. Unidentified fossils from the same genus also had been discovered from the nearby Wulongqing Formation (Cambrian Stage 4). [3]

Contents

Classification

Initially, Parapeytoia was interpreted as a radiodont ("anomalocaridid" at that time) dinocaridid with legs alongside Cucumericrus , [1] purported to be an indicator that radiodonts might have legs underneath their body flaps in general, comparable to Pambdelurion . [4] With the combination of megacheiran and presumably radiodont features (see text), it was also suggest to be an intermediate form between the two taxa. [5] [6] However, later studies reveal it most likely nested within megacheirans, [7] [8] [9] [10] [11] [12] [13] [14] and megacheirans was no longer thought to be originated from radiodonts since than. [15] Within megacheirans, Parapeytoia possibly closest to the multisegmented (with over 20 trunk segments) taxa like Fortiforceps and Jianfengia , united under the family Jianfengiidae. [14]

Description

Interpretations on Parapeytoia yunnanensis as a radiodont (A) and jianfengiid megacheiran (B) respectively. Red parts indicating suggested radiodont-like features with questionable affinity. Dark grey indicating other structures unambiguously belong to this species. 20191021 Parapeytoia yunnanensis interpretation.png
Interpretations on Parapeytoia yunnanensis as a radiodont (A) and jianfengiid megacheiran (B) respectively. Red parts indicating suggested radiodont-like features with questionable affinity. Dark grey indicating other structures unambiguously belong to this species.

Parapeytoia is known from a few incomplete fossil materials with part of its ventral structures preserved. The frontmost appendages were a pair of great appendages that form by a robust peduncle and 4 distal segments with serrated spine on each of them, a feature shared by some other megacheirans such as Yohoia and Fortiforceps . [16] [17] Behind the great appendages were 2 or 3 pairs of short appendages, and numerous pairs of well-developed biramous appendages, each formed by a basipod with spiny gnathobase, lobe-like exopod and leg-like endopod with 8 segments. A narrow, hourglass-like sternite associated between each of those appendages. [1]

Some features originally interpreted as radiodont-like are more or less questionable, such as radial sclerites interpreted as its mouthparts (oral cone) have since been assigned to another genus of animal, Omnidens . [18] While some subsequent studies suggest those features are genuine, it most likely represent ancestral traits originated from more basal arthropods instead of any indicators of radiodont affinities. [19] The same goes with gnathobases, [20] and the presence of arthropodized endopods underneath the purported body flaps (exopods) conflict with the component of radiodont trunk appendages as well (the radiodont ventral body flaps are most likely homologous to euarthropod endopods). [13]

Parapeytoia was in all likelihood a benthic feeder, spending most of its time on the ocean floor hunting (or possibly scavenging) for prey. [12]

Related Research Articles

<span class="mw-page-title-main">Lobopodia</span> Group of extinct worm-like animals with legs

Lobopodians are members of the informal group Lobopodia, or the formally erected phylum Lobopoda Cavalier-Smith (1998). They are panarthropods with stubby legs called lobopods, a term which may also be used as a common name of this group as well. While the definition of lobopodians may differ between literatures, it usually refers to a group of soft-bodied, marine worm-like fossil panarthropods such as Aysheaia and Hallucigenia.

<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>Amplectobelua</i> Extinct genus of radiodont

Amplectobelua is an extinct genus of late Early Cambrian amplectobeluid radiodont, a group of stem arthropods that mostly lived as free-swimming predators during the first half of the Paleozoic Era.

<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.

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

Megacheira is an extinct class of predatory arthropods defined by their possession of spined "great appendages". Their taxonomic position is controversial, with studies either considering them stem-group euarthropods, or stem-group chelicerates. The homology of the great appendages to the cephalic appendages of other arthropods is also controversial. Uncontested members of the group were present in marine environments worldwide from the lower to middle Cambrian.

<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.

<i>Occacaris</i> Extinct genus of arthropods

Occacaris oviformis is an extinct nektonic predatory arthropod from the Lower Cambrian Maotianshan shale Lagerstätte. It bears a superficial resemblance to the Cambrian arthropod, Canadaspis, though, was much smaller, and had a pair of "great appendages", with which it may have grasped prey. It was originally considered to belong to Megacheira, however it is questioned in later study.

<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>Cucumericrus</i> Extinct genus of arthropod

Cucumericrus ("cucumber-leg") is an extinct genus of stem-arthropod. The type and only species is Cucumericrus decoratus, with fossils discovered from the Maotianshan Shales of Yunnan, China.

<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. It was first named by Allison C. Daley and Graham E. Budd in 2010, being the type species Caryosyntrips serratus.

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

Lyrarapax is a radiodont genus of the family Amplectobeluidae that lived in the early Cambrian period 520 million years ago. Its neural tissue indicates that the radiodont frontal appendage is protocerebral, resolving parts of the arthropod head problem and showing that the frontal appendage is homologous to the antennae of Onychophorans and labrum of euarthropods. Its fossilized remains were found in Yunnan in southwestern China. A second species was described in 2016, differing principally in the morphology of its frontal appendages. It is a small animal, with L. unguispinus and L. trilobus measuring up to 8.3 cm (3.3 in) and 3.9 cm (1.5 in) in body length respectively.

<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.

<span class="mw-page-title-main">Artiopoda</span> Extinct group of arthropods

The Artiopoda is a grouping of extinct arthropods that includes trilobites and their close relatives. It was erected by Hou and Bergström in 1997 to encompass a wide diversity of arthropods that would traditionally have been assigned to the Trilobitomorpha. Trilobites, in part due to abundance of findings owing to their mineralized exoskeletons, are by far the best recorded, diverse, and long lived members of the clade. Other members, which lack mineralised exoskeletons, are known mostly from Cambrian deposits.

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

Hymenocarina is an order of extinct arthropods known from the Cambrian. They possess bivalved carapaces, typically with exposed posteriors. Members of the group are morphologically diverse and had a variety of ecologies, including as filter feeders and as predators. Recent research has generally considered them to be stem or crown group members of Mandibulata, due to the presence of mandibles in some species.

<i>Kylinxia</i> Genus of fossil arthropod

Kylinxia is a genus of extinct arthropod described in 2020. It was described from six specimens discovered in Yu'anshan Formation in southern China. The specimens are assigned to one species Kylinxia zhangi. Dated to 518 million years, the fossils falls under the Cambrian period. Announcing the discovery on 4 November 2020 at a press conference, Zeng Han of the Nanjing Institute of Geology and Paleontology, said that the animal "bridges the evolutionary gap from Anomalocaris to true arthropods and forms a key ‘missing link’ in the origin of arthropods," which was "predicted by Darwin’s evolutionary theory." The same day the formal description was published in Nature.

<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>Erratus</i> Extinct genus of Cambrian arthropod

Erratus is an extinct genus of marine arthropod from the Cambrian of China. Its type and only species is Erratus sperare. Erratus is likely one of the most basal known arthropods, and its discovery has helped scientists understand the early evolution of arthropod trunk appendages. Some of the stem-arthropods like radiodonts did not have legs, instead they had flap like appendages that helped them swim. Erratus on the other hand had not only flaps but also a set of primitive legs. It also supported the theory that the gills of aquatic arthropods probably evolved into the wings and lungs of terrestrial arthropods later in the Paleozoic.

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

Deuteropoda is a proposed clade of arthropods whose members are distinguished from more basal stem-group arthropods like radiodonts by an anatomical reorganization of the head region, namely the appearance of a differentiated first appendage pair, a multisegmented head, a hypostome/labrum complex, and by bearing pairs of segmented biramous limbs.

<i>Fortiforceps</i> Extinct genus of arthropods

Fortiforceps is an extinct genus of Cambrian megacheiran arthropod known from the Chengjiang biota of Yunnan, China. It was originally described by Hou and Bergström in 1997, and redescribed in 2020. It was relatively small, at 4 centimetres (1.6 in) or less in length. The head had a large pair of stalked eyes, a pair of frontal projections, as well as a pair of great appendages, like other megacheirans, along with two other cephalic appendages. The trunk had either 20 or 22 segments, depending on the specimen. These segments had pronounced blade-like spines on their upper-outer edge. Each of the trunk segments were associated with pairs of biramous limbs, which probably have seven podomeres and like other megacheirans, have paddle-shaped exopods. The trunk terminated with a forked tailpiece, which on their outer edges had rod-like structures. The two lobes were separated by a rectangular central piece. It has been placed as a member of the family Jiangfengiidae, alongside Jianfengia, Sklerolibyon and possibly Parapeytoia.

References

  1. 1 2 3 4 Xian-Guang, Hou; Bergström, Jan; Ahlberg, Per (1995-09-01). "Anomalocaris and other large animals in the lower Cambrian Chengjiang fauna of southwest China". GFF. 117 (3): 163–183. Bibcode:1995GFF...117..163X. doi:10.1080/11035899509546213. ISSN   1103-5897.
  2. Yang, Chuan; Li, Xian-Hua; Zhu, Maoyan; Condon, Daniel J.; Chen, Junyuan (2018). "Geochronological constraint on the Cambrian Chengjiang biota, South China". Journal of the Geological Society. 175 (4): 659–666. Bibcode:2018JGSoc.175..659Y. doi:10.1144/jgs2017-103. ISSN   0016-7649. S2CID   135091168.
  3. Hu, ShiXue; Zhu, MaoYan; Steiner, Michael; Luo, HuiLin; Zhao, FangChen; Liu, Qi (2010-12-01). "Biodiversity and taphonomy of the Early Cambrian Guanshan biota, eastern Yunnan". Science China Earth Sciences. 53 (12): 1765–1773. Bibcode:2010ScChD..53.1765H. doi:10.1007/s11430-010-4086-9. ISSN   1869-1897. S2CID   128882075.
  4. Xianguang, Hou; Jan, Jan Bergström; Jiayu, In Rong; Zongjie, Fang; Zhanghe, Zhou; Renbin, Zhan; Xiangdong, Wang; (eds, Yuan Xunlai et al. (2006). Dinocaridids - anomalous arthropods or arthropod-like worms?.
  5. Budd, Graham E. (2002). "A palaeontological solution to the arthropod head problem". Nature. 417 (6886): 271–275. Bibcode:2002Natur.417..271B. doi:10.1038/417271a. ISSN   1476-4687. S2CID   4310080.
  6. Chen, Junyuan; Waloszek, Dieter; Maas, Andreas (2004). "A new 'great-appendage' arthropod from the Lower Cambrian of China and homology of chelicerate chelicerae and raptorial antero-ventral appendages". Lethaia. 37 (1): 3–20. doi:10.1080/00241160410004764. ISSN   0024-1164.
  7. Daley, Allison C.; Budd, Graham E.; Caron, Jean-Bernard; Edgecombe, Gregory D.; Collins, Desmond (2009-03-20). "The Burgess Shale Anomalocaridid Hurdia and Its Significance for Early Euarthropod Evolution". Science. 323 (5921): 1597–1600. Bibcode:2009Sci...323.1597D. doi:10.1126/science.1169514. ISSN   0036-8075. PMID   19299617. S2CID   206517995.
  8. Stein, Martin (2010-03-01). "A new arthropod from the Early Cambrian of North Greenland, with a 'great appendage'-like antennula". Zoological Journal of the Linnean Society. 158 (3): 477–500. doi:10.1111/j.1096-3642.2009.00562.x. ISSN   0024-4082.
  9. Legg, David A.; Sutton, Mark D.; Edgecombe, Gregory D.; Caron, Jean-Bernard (2012). "Cambrian bivalved arthropod reveals origin of arthrodization". Proceedings of the Royal Society B: Biological Sciences. 279 (1748): 4699–4704. doi:10.1098/rspb.2012.1958. ISSN   0962-8452. PMC   3497099 . PMID   23055069.
  10. Legg, David A.; Sutton, Mark D.; Edgecombe, Gregory D. (2013-09-30). "Arthropod fossil data increase congruence of morphological and molecular phylogenies". Nature Communications. 4 (1): 2485. Bibcode:2013NatCo...4.2485L. doi:10.1038/ncomms3485. ISSN   2041-1723. PMID   24077329.
  11. Daley, Allison C.; Edgecombe, Gregory D. (2014). "Morphology of Anomalocaris canadensis from the Burgess Shale". Journal of Paleontology. 88 (1): 68–91. Bibcode:2014JPal...88...68D. doi:10.1666/13-067. ISSN   0022-3360. S2CID   86683798.
  12. 1 2 Xian-Guang, Hou; Siveter, David J.; Siveter, Derek J.; Aldridge, Richard J.; Pei-Yun, Cong; Gabbott, Sarah E.; Xiao-Ya, Ma; Purnell, Mark A.; Williams, Mark (2017-04-24). The Cambrian Fossils of Chengjiang, China: The Flowering of Early Animal Life. John Wiley & Sons. ISBN   9781118896389.
  13. 1 2 Van Roy, Peter; Daley, Allison C.; Briggs, Derek E. G. (2015-06-04). "Anomalocaridid trunk limb homology revealed by a giant filter-feeder with paired flaps". Nature. 522 (7554): 77–80. Bibcode:2015Natur.522...77V. doi:10.1038/nature14256. ISSN   1476-4687. PMID   25762145. S2CID   205242881.
  14. 1 2 Aria, Cédric; Zhao, Fangchen; Zeng, Han; Guo, Jin; Zhu, Maoyan (2020). "Fossils from South China redefine the ancestral euarthropod body plan". BMC Evolutionary Biology. 20 (1): 4. Bibcode:2020BMCEE..20....4A. doi: 10.1186/s12862-019-1560-7 . ISSN   1471-2148. PMC   6950928 . PMID   31914921.
  15. Ortega-Hernández, Javier; Janssen, Ralf; Budd, Graham E. (2017-05-01). "Origin and evolution of the panarthropod head – A palaeobiological and developmental perspective". Arthropod Structure & Development. Evolution of Segmentation. 46 (3): 354–379. doi: 10.1016/j.asd.2016.10.011 . ISSN   1467-8039. PMID   27989966.
  16. Haug, Joachim T.; Waloszek, Dieter; Maas, Andreas; Liu, Yu; Haug, Carolin (March 2012). "Functional morphology, ontogeny and evolution of mantis shrimp-like predators in the Cambrian". Palaeontology. 55 (2): 369–399. Bibcode:2012Palgy..55..369H. doi: 10.1111/j.1475-4983.2011.01124.x . S2CID   82841481.
  17. Zeng, Han; Zhao, Fangchen; Niu, Kecheng; Zhu, Maoyan; Huang, Diying (2020). "An early Cambrian euarthropod with radiodont-like raptorial appendages". Nature. 588 (7836): 101–105. Bibcode:2020Natur.588..101Z. doi:10.1038/s41586-020-2883-7. ISSN   1476-4687. PMID   33149303. S2CID   226248177.
  18. Hou, Xianguang; Bergström, Jan; Jie, Yang (2006). "Distinguishing anomalocaridids from arthropods and priapulids". Geological Journal. 41 (3–4): 259–269. Bibcode:2006GeolJ..41..259X. doi:10.1002/gj.1050. S2CID   83582128.
  19. Budd, Graham E. (2021-05-01). "The origin and evolution of the euarthropod labrum". Arthropod Structure & Development. 62: 101048. doi:10.1016/j.asd.2021.101048. ISSN   1467-8039.
  20. Cong, Peiyun; Daley, Allison C.; Edgecombe, Gregory D.; Hou, Xianguang (2017). "The functional head of the Cambrian radiodontan (stem-group Euarthropoda) Amplectobelua symbrachiata". BMC Evolutionary Biology. 17 (1): 208. Bibcode:2017BMCEE..17..208C. doi: 10.1186/s12862-017-1049-1 . ISSN   1471-2148. PMC   5577670 . PMID   28854872.