似奇蝦屬
似奇蝦屬(學名:Paranomalocaris)是節肢動物門、恐蝦綱、放射齒目、地位未定的一屬,底下有兩個物種,分別是多節似奇蝦(學名:Paranomalocaris multisegmentalis)和簡單似奇蝦(學名:Paranomalocaris simplex)。化石在現今中國東南部的澄江化石地被發現的。[1][2][3]目前僅發現似奇蝦的前附肢化石,身體等的部分仍不清楚,間接導致似奇蝦的分類具有爭議。[3]
似奇蝦屬 | |
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似奇蝦的前附肢復原圖 | |
科學分類 | |
界: | 動物界 Animalia |
門: | 節肢動物門 Arthropoda |
綱: | †恐蝦綱 Dinocaridida |
目: | †放射齒目 Radiodonta |
科: | †地位未定 incertae sedis |
屬: | †似奇蝦屬 Paranomalocaris Wang, Huang & Hu, 2013 |
模式種 | |
多節似奇蝦 Paranomalocaris multisegmentalis Wang, Huang & Hu, 2013
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其他物種 | |
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發現
似奇蝦的標本在中國雲南東部昆明高樓坊村(Gaoloufang Village)烏龍箐地層(Wulongqing Formation)的關山動物群(Guanshan biota)[1][2]與關山蝦屬一樣[1][2][4][5],在李花村(Lihua Village)附近的的李花莊階層(Lihuazhuang section)也有發現。多節似奇蝦一開始僅發現一個標本,編號為NIGP 154564[2],在李花莊段也有發現一個標本,編號為YKLP 12416。簡單似奇蝦則是僅在李花莊段發現標本,編號是YKLP 12417和YKLP 12418。[1]
命名
Paranomalocaris是由「para」(相近、類似)+「Anomalocaris」(奇蝦的屬名);而多節似奇蝦(Paranomalocaris multisegmentalis)的種小名-「multisegmentalis」是「multi」(許多)+「segmental」(一節一節的);[1]簡單似奇蝦(Paranomalocaris simplex)的種小名-「simplex」(簡單)比起同屬的多節似奇蝦前附肢結構簡單許多。[2]
型態
多節似奇蝦的前附肢全長32至45毫米,共有23個節,前段與末端的節,高會比寬還要長;但中段則是寬長於高。前附肢的第一節和第二節在第一次被描述同為一節,兩節的末端各有一對較小的刺。在第三節到第二十二節都有一對刺,且刺的大小交替。第五和更後面的節刺上有三到六對較小的刺,大約位在刺與前附肢的連接點。在第十三到第二十二節的背緣有著六根小刺,且會逐漸變大。在最後一節有兩根刺。[1][2]前附肢末端的刺雖然很小,但附肢細長且分節更多,使附肢可以更加地彎曲,刺相對短小但很尖銳,且小刺能牢固地抓住獵物。[1]
簡單似奇蝦的前附肢全長32至33毫米,可能有超過20個節,每節的外觀類似於長方形。每節都有一對類似針的刺,且愈末端愈短。在化石上雖然有發現到刺上面有著更小的刺,但是大多發現都是光滑且沒有小刺在上的,在末端的節上只有一根彎曲的刺,且每個前附肢末端的三分之一的背緣都有刺。[2]
分類
似奇蝦屬的分類具有爭議,一種是認為是似奇蝦屬屬於奇蝦科和抱怪蟲科的類群[1][2][6][7][8],另一種則是歸類在放射齒目的奇蝦亞目的基群物種。[9][10][3]
Joseph Moysiuk和Jean-Bernard Caron提出的分類圖:[8]
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Gaëtan J.-M. Potin和Allison C. Daley提出的分類圖:[3]
胡桃鉗蟲屬 Caryosyntrips | ||||||||||||||||||||||
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次足類 Deuteropoda | ||||||||||||||||||||||
2024年,吳雨等假設似奇蝦為奇蝦科的一屬,那位置如下:[11]
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參考資料
- ^ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Wang, YuanYuan; Huang, DiYing; Hu, ShiXue. New anomalocardid frontal appendages from the Guanshan biota, eastern Yunnan. Chinese Science Bulletin. 2013-06-07, 58 (32) [2024-06-16]. ISSN 1001-6538. doi:10.1007/s11434-013-5908-x. (原始內容存檔於2022-09-22).
- ^ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Jiao, De-guang; Pates, Stephen; Lerosey-Aubril, Rudy; Ortega-Hernandez, Javier; Yang, Jie; Lan, Tian; Zhang, Xi-guang. The endemic radiodonts of the Cambrian Stage 4 Guanshan biota of South China. Acta Palaeontologica Polonica. 2021, 66 [2024-06-17]. ISSN 0567-7920. doi:10.4202/app.00870.2020. (原始內容存檔於2023-04-20).
- ^ 3.0 3.1 3.2 3.3 Potin, Gaëtan J.-M.; Daley, Allison C. The significance of Anomalocaris and other Radiodonta for understanding paleoecology and evolution during the Cambrian explosion. Frontiers in Earth Science. 2023-05-09, 11. ISSN 2296-6463. doi:10.3389/feart.2023.1160285.
- ^ Wang, YuanYuan; Huang, DiYing; Hu, ShiXue. New anomalocardid frontal appendages from the Guanshan biota, eastern Yunnan. Chinese Science Bulletin. 2013-06-07, 58 (32). ISSN 1001-6538. doi:10.1007/s11434-013-5908-x.
- ^ Zhang, Mingjing; Wu, Yu; Lin, Weiliang; Ma, Jiaxin; Wu, Yuheng; Fu, Dongjing. Amplectobeluid Radiodont Guanshancaris gen. nov. from the Lower Cambrian (Stage 4) Guanshan Lagerstätte of South China: Biostratigraphic and Paleobiogeographic Implications. Biology. 2023-04-11, 12 (4). ISSN 2079-7737. doi:10.3390/biology12040583.
- ^ Van Roy, Peter; Daley, Allison C.; Briggs, Derek E. G. Anomalocaridid trunk limb homology revealed by a giant filter-feeder with paired flaps. Nature. 2015-03-11, 522 (7554). ISSN 0028-0836. doi:10.1038/nature14256.
- ^ Cong, C; Ma, M; Hou, H; Edgecombe, E; Strausfeld, S. Brain structure resolves the segmental affinity of anomalocaridid appendages. MorphoBank datasets. 2015 [2024-01-17]. (原始內容存檔於2024-01-17).
- ^ 8.0 8.1 Moysiuk, Joseph; Caron, Jean-Bernard. Exceptional multifunctionality in the feeding apparatus of a mid-Cambrian radiodont. Paleobiology. 2021-05-17, 47 (4). ISSN 0094-8373. doi:10.1017/pab.2021.19.
- ^ Lerosey-Aubril, Rudy; Pates, Stephen. New suspension-feeding radiodont suggests evolution of microplanktivory in Cambrian macronekton. Nature Communications. 2018-09-14, 9 (1) [2024-01-17]. ISSN 2041-1723. doi:10.1038/s41467-018-06229-7. (原始內容存檔於2021-10-07).
- ^ Liu, Jianni; Lerosey-Aubril, Rudy; Steiner, Michael; Dunlop, Jason A; Shu, Degan; Paterson, John R. Origin of raptorial feeding in juvenile euarthropods revealed by a Cambrian radiodontan. National Science Review. 2018-06-01, 5 (6). ISSN 2095-5138. doi:10.1093/nsr/nwy057.
- ^ Wu, Yu; Pates, Stephen; Liu, Cong; Zhang, Mingjing; Lin, Weiliang; Ma, Jiaxin; Wu, Yuheng; Chai, Shu; Zhang, Xingliang; Fu, Dongjing. A new radiodont from the lower Cambrian (Series 2 Stage 3) Chengjiang Lagerstätte, South China informs the evolution of feeding structures in radiodonts. Journal of Systematic Palaeontology. 2024-12-31, 22 (1). ISSN 1477-2019. doi:10.1080/14772019.2024.2364887 (英語).