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Introvert and pharynx of Mafangscolex, a Cambrian palaeoscolecid

Published online by Cambridge University Press:  21 April 2020

Jie Yang ,
Martin R Smith Open the ORCID record for Martin R Smith [Opens in a new window] ,
Xi-guang Zhang  and
Xiao-yu Yang Open the ORCID record for Xiao-yu Yang [Opens in a new window]
Jie Yang
Affiliation:
Key Laboratory for Palaeobiology, Yunnan University, Kunming650091, China MEC International Joint Laboratory for Palaeobiology and Palaeoenvironment, Yunnan University, Kunming650091, China
Martin R Smith
Affiliation:
Department of Earth Sciences, Durham University, Durham, DH1 3LE, UK
Xi-guang Zhang
Affiliation:
Key Laboratory for Palaeobiology, Yunnan University, Kunming650091, China MEC International Joint Laboratory for Palaeobiology and Palaeoenvironment, Yunnan University, Kunming650091, China
Xiao-yu Yang*
Affiliation:
Key Laboratory for Palaeobiology, Yunnan University, Kunming650091, China MEC International Joint Laboratory for Palaeobiology and Palaeoenvironment, Yunnan University, Kunming650091, China
*
Author for correspondence: Xiao-yu Yang, Email: [email protected]
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Abstract

Palaeoscolecid worms are widespread in the Palaeozoic period, and are of key importance to understanding the emergence of moulting animals (superphylum Ecdysozoa). However, palaeoscolecids lack a diagnostic set of morphological characters, and as such are unlikely to form a natural (monophyletic) group. Consequently, detailed anatomical study of individual taxa is necessary in order to evaluate the phylogenetic significance of palaeoscolecids. New specimens of Mafangscolex from the Cambrian Stage 3 Xiaoshiba Lagerstätte in Kunming, China, provide the first detailed account of a proboscis in Palaeoscoelcida sensu stricto, a core group of palaeoscolecids characterized by having a tessellating scleritome of phosphatic plates and platelets. The eversible mouthparts of Mafangscolex comprise an armoured, hexaradially symmetrical introvert, a ring of coronal spines and quincuncially arranged pharyngeal armature, with a range of tooth morphologies. Taken together, this configuration strikingly resembles the proboscis arrangement inferred for the ancestral ecdysozoan. The six-fold symmetry represents an important difference from the pentaradial priapulan proboscis. The retention of key aspects of the ancestral ecdysozoan body plan suggests that palaeoscolecids represent a useful window on the earliest stages of ecdysozoan evolution.

Keywords

Palaeoscoelcida sensu strictoproboscisecdysozoan evolutionXiaoshiba LagerstätteCambrian Stage 3
Type
Original Article
Information
Geological Magazine , Volume 157 , Issue 12 , December 2020 , pp. 2044 - 2050
Copyright
© Cambridge University Press 2020

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References

Adrianov, AV and Malakhov, VV (2001) Symmetry of priapulids (Priapulida). 1. Symmetry of adults. Journal of Morphology 247, 99–110.3.0.CO;2-0>CrossRefGoogle ScholarPubMed
Biserova, NM and Kuznetsova, KG (2012) Head sensory organs of Halobiotus stenostomus (Eutardigrada, Hypsibiidae). Biology Bulletin 39, 579–89.CrossRefGoogle Scholar
Boesgaard, TM and Kristensen, RM (2001) Tardigrades from Australian marine caves. With a redescription of Actinarctus neretinus (Arthrotardigrada). Zoologischer Anzeiger 240, 253–64.CrossRefGoogle Scholar
Budd, GE (2001) Tardigrades as ‘stem-group arthropods’: the evidence from the Cambrian fauna. Zoologischer Anzeiger 240, 265–79.CrossRefGoogle Scholar
Butterfield, NJ and Harvey, THP (2012) Small Carbonaceous Fossils (SCFs): a new measure of early Paleozoic paleobiology. Geology 40, 71–4.CrossRefGoogle Scholar
Chen, AL, Parry, LA, Fan, W, Vinther, J and Cong, PY (2018) Giant stem group gastrotrichs from the early Cambrian. In The Palaeontological Association 62nd Annual Meeting, University of Bristol, 14–17 December 2018, Programme, Abstracts and AGM papers, 29.Google Scholar
Conway Morris, S (1977) Fossil priapulid worms. Special Papers in Palaeontology 20, 1–95.Google Scholar
Conway Morris, S (1997) The cuticular structure of the 495-Myr-old type species of the fossil worm Palaeoscolex, P. piscatorum (? Priapulida). Zoological Journal of the Linnean Society 119, 69–82.CrossRefGoogle Scholar
Conway Morris, S and Peel, JS (2010) New palaeoscolecidan worms from the Lower Cambrian: Sirius Passet, Latham Shale and Kinzers Shale. Acta Palaeontologica Polonica 55, 141–56.CrossRefGoogle Scholar
Conway Morris, S and Robison, RA (1986) Middle Cambrian priapulids and other soft-bodied fossils from Utah and Spain. University of Kansas Paleontological Contributions 117, 1–22.Google Scholar
Dong, XP, Bengtson, S, Gostling, NJ, Cunningham, JA, Harvey, THP, Kouchinsky, AV, Val’kov, AK, Repetski, JE, Stampanoni, M, Marone, F and Donoghue, PCJ (2010) The anatomy, taphonomy, taxonomy and systematic affinity of Markuelia: Early Cambrian to Early Ordovician scalidophorans. Palaeontology 53, 1291–314.CrossRefGoogle Scholar
Dzik, J (1991) Is fossil evidence consistent with traditional views of the early metazoan phylogeny? In The Early Evolution of Metazoa and the Significance of Problematic Taxa (eds Simonetta, AM and Conway Morris, S), pp. 47–56. Cambridge: Cambridge University Press.Google Scholar
García-Bellido, DC, Paterson, JR and Edgecombe, GD (2013) Cambrian palaeoscolecids (Cycloneuralia) from Gondwana and reappraisal of species assigned to Palaeoscolex . Gondwana Research 24, 780–95.CrossRefGoogle Scholar
Glaessner, MF (1979) Lower Cambrian Crustacea and annelid worms from Kangaroo Island, South Australia. Alcheringa 3, 21–31.CrossRefGoogle Scholar
Guidetti, R, Peluffo, JR, Rocha, AM, Cesari, M and De Peluffo, MCM (2013) The morphological and molecular analyses of a new South American urban tardigrade offer new insights on the biological meaning of the Macrobiotus hufelandi group of species (Tardigrada: Macrobiotidae). Journal of Natural History 47, 2409–26.CrossRefGoogle Scholar
Han, J, Yao, Y, Zhang, ZF, Liu, JN and Shu, DG (2007) New observations on the palaeoscolecid worm Tylotites petiolaris from the Cambrian Chengjiang Lagerstätte, south China. Paleontological Research 11, 59–69.Google Scholar
Harvey, THP, Dong, XP and Donoghue, PCJ (2010) Are palaeoscolecids ancestral ecdysozoans? Evolution & Development 12, 177–200.CrossRefGoogle ScholarPubMed
Hou, XG and Bergström, J (1994) Palaeoscolecid worms may be nematomorphs rather than annelids. Lethaia 27, 11–7.Google Scholar
Hou, JB, Hughes, NC, Yang, J, Lan, T, Zhang, XG and Dominguez, C (2017) Ontogeny of the articulated yiliangellinine trilobite Zhangshania typica from the lower Cambrian (Series 2, Stage 3) of southern China. Journal of Paleontology 91, 86–99.CrossRefGoogle Scholar
Hou, XG and Sun, WG (1988) Discovery of Chengjiang Fauna at Meishucun, Jinning, Yunnan. Acta Palaeontologica Sinica 27, 1–12 (in Chinese with English summary).Google Scholar
Hu, SX (2005) Taphonomy and palaeoecology of the early Cambrian Chengjiang Biota from eastern Yunnan, China. Berliner Paläobiologische Abhandlungen 7, 1–197.Google Scholar
Hu, SX, Li, Y, Luo, HL, Fu, XP, You, T, Pang, JY, Liu, Q and Steiner, M (2008) New record of palaeoscolecids from the Early Cambrian of Yunnan, China. Acta Geologica Sinica 82, 244–8.Google Scholar
Huang, DY, Vannier, J and Chen, JY (2004) Recent Priapulidae and their Early Cambrian ancestors: comparisons and evolutionary significance. Geobios 37, 217–28.CrossRefGoogle Scholar
Kesidis, G, Slater, BJ, Jensen, S and Budd, GE (2019) Caught in the act: priapulid burrowers in early Cambrian substrates. Proceedings of the Royal Society B: Biological Sciences 286, 20182505. doi: 10.1098/rspb.2018.2505.CrossRefGoogle ScholarPubMed
Kouraiss, K, El Hariri, K, El Albani, A, Azizi, A, Mazurier, A and Vannier, J (2018) X-ray microtomography applied to fossils preserved in compression: palaeoscolescid worms from the Lower Ordovician Fezouata Shale. Palaeogeography, Palaeoclimatology, Palaeoecology 508, 48–58.CrossRefGoogle Scholar
Kraft, P and Mergl, M (1989) Worm-like fossils (Palaeoscolecida, Chaetognatha) from the Lower Ordovician of Bohemia. Sborník Geologických Věd Paleontologie 30, 9–36.Google Scholar
Lan, T, Yang, J, Hou, JB and Zhang, XG (2015) The feeding behaviour of the Cambrian tubiculous priapulid Selkirkia . Lethaia 48, 125–32.Google Scholar
Liu, YH, Qin, JC, Wang, Q, Maas, A, Duan, BC, Zhang, YN, Zhang, H, Shao, TQ and Zhang, HQ (2019) New armoured scalidophorans (Ecdysozoa, Cycloneuralia) from the Cambrian Fortunian Zhangjiagou Lagerstätte, South China. Papers in Palaeontology 5, 241–60.CrossRefGoogle Scholar
Liu, YH, Xiao, SH, Shao, TQ, Broce, J and Zhang, HQ (2014) The oldest known priapulid-like scalidophoran animal and its implications for the early evolution of cycloneuralians and ecdysozoans. Evolution & Development 165, 155–65.CrossRefGoogle Scholar
Luo, HL, Hu, SX, Han, J, Zhang, SS, Zhan, DQ, Lu, YX and Yao, XY (2014) Restudy of palaeoscolecidians from the Meishucun Section, Jinning, Yunnan, China. Journal of Northwest University (Natural Science Edition) 44, 947–53 (in Chinese with English summary).Google Scholar
Luo, HL and Zhang, SS (1986) Early Cambrian worms and trace fossils in Jinning and Anning, Yunnan Province. Acta Palaeontologica Sinica 25, 307–11 (in Chinese with English summary).Google Scholar
Maas, A, Waloszek, D, Haug, JT and Müller, KJ (2007) A possible larval roundworm from the Cambrian “Orsten” and its bearing on the phylogeny of Cycloneuralia. Memoirs of the Association of Australasian Palaeontologists 34, 499–519.Google Scholar
Martin, ELO, Lerosey-Aubril, R and Vannier, J (2016) Palaeoscolecid worms from the Lower Ordovician Fezouata Lagerstätte, Morocco: palaeoecological and palaeogeographical implications. Palaeogeography, Palaeoclimatology, Palaeoecology 460, 130–41.CrossRefGoogle Scholar
Müller, KJ and Hinz-Schallreuter, I (1993) Palaeoscolecid worms from the Middle Cambrian of Australia. Palaeontology 36, 549–92.Google Scholar
Peel, JS (2017) Feeding behaviour of a new worm (Priapulida) from the Sirius Passet Lagerstätte (Cambrian Series 2, Stage 3) of North Greenland (Laurentia). Palaeontology 60, 795–805.CrossRefGoogle Scholar
Peel, JS, Stein, M and Kristensen, RM (2013) Life cycle and morphology of a Cambrian stem-lineage loriciferan. PLoS ONE 8, e73583. doi: 10.1371/journal.pone.0073583.CrossRefGoogle ScholarPubMed
Slater, BJ, Harvey, THP, Guilbaud, R and Butterfield, NJ (2017) A cryptic record of Burgess Shale-type diversity from the early Cambrian of Baltica. Palaeontology 60, 117–40.CrossRefGoogle Scholar
Smith, MR (2015) A palaeoscolecid worm from the Burgess Shale. Palaeontology 58, 973–9.CrossRefGoogle Scholar
Smith, MR and Caron, JB (2015) Hallucigenia’s head and the pharyngeal armature of early ecdysozoans. Nature 523, 75–8.CrossRefGoogle ScholarPubMed
Smith, MR, Harvey, THP and Butterfield, NJ (2015) The macro- and microfossil record of the Cambrian priapulid Ottoia . Palaeontology 58, 705–21.CrossRefGoogle Scholar
Smith, MR and Zhang, ZF (2018) A Cambrian peanut worm and the peramorphic origin of the sipunculan body plan. In The Palaeontological Association 62nd Annual Meeting, University of Bristol, 14–17 December 2018, Programme, Abstracts and AGM papers, 54.Google Scholar
Sørensen, MV, Hebsgaard, MB, Heiner, I, Glenner, H, Willerslev, E and Kristensen, RM (2008) New data from an enigmatic phylum: evidence from molecular sequence data supports a sister-group relationship between Loricifera and Nematomorpha. Journal of Zoological Systematics and Evolutionary Research 46, 231–9.CrossRefGoogle Scholar
Steiner, M, Hu, SX, Liu, JN and Keupp, H (2012) A new species of Hallucigenia from the Cambrian Stage 4 Wulongqing Formation of Yunnan (South China) and the structure of sclerites in lobopodians. Bulletin of Geosciences 87, 107–24.CrossRefGoogle Scholar
van den Boogaard, M (1989) Isolated tubercles of some Palaeoscolecida. Scripta Geologica 90, 1–12.Google Scholar
van der Land, J (1970) Systematics, zoogeography, and ecology of the Priapulida. Zoologische Verhandelingen 112, 1–118.Google Scholar
Vannier, J and Martin, ELO (2017) Worm-lobopodian assemblages from the Early Cambrian Chengjiang biota: insight into the “pre-arthropodan ecology”? Palaeogeography, Palaeoclimatology, Palaeoecology 469, 373–87.CrossRefGoogle Scholar
Wang, WJ, Muir, LA, Botting, JP, Feng, HZ, Servais, T and Li, LX (2014) A Tremadocian (Early Ordovician) palaeoscolecidan worm from graptolitic shales in Hunan Province, South China. Palaeontology 57, 657–71.CrossRefGoogle Scholar
Whitaker, AF, Jamison, PG, Schiffbauer, JD and Kimmig, J (2020) Re-description of the Spence Shale palaeoscolecids in light of new morphological features with comments on palaeoscolecid taxonomy and taphonomy. PalZ, published online 26 February 2020. doi: 10.1007/s12542-020-00516-9.CrossRefGoogle Scholar
Whittard, WF (1953) Palaeoscolex piscatorum gen. et sp. nov., a worm from the Tremadocian of Shropshire. Quarterly Journal of the Geological Society of London 109, 125–35.CrossRefGoogle Scholar
Whittington, HB (1978) The lobopod animal Aysheaia pedunculata Walcott, Middle Cambrian, Burgess Shale, British Columbia. Philosophical Transactions of the Royal Society of London B: Biological Sciences 284, 165–97.Google Scholar
Wills, MA (1998) Cambrian and Recent disparity: the picture from priapulids. Paleobiology 24, 177–99.Google Scholar
Wills, MA, Gerber, S, Ruta, M and Hughes, M (2012) The disparity of priapulid, archaeopriapulid and palaeoscolecid worms in the light of new data. Journal of Evolutionary Biology 25, 2056–76.CrossRefGoogle ScholarPubMed
Yang, J, Ortega-Hernández, J, Butterfield, NJ and Zhang, XG (2013) Specialized appendages in fuxianhuiids and the head organization of early euarthropods. Nature 494, 468–71.CrossRefGoogle ScholarPubMed
Yang, J, Ortega-Hernández, J, Gerber, S, Butterfield, NJ, Hou, JB, Lan, T and Zhang, XG (2015) A superarmored lobopodian from the Cambrian of China and early disparity in the evolution of Onychophora. Proceedings of the National Academy of Sciences 112, 8678–83.CrossRefGoogle ScholarPubMed
Yang, J, Ortega-Hernández, J, Legg, DA, Lan, T, Hou, JB and Zhang, XG (2018) Early Cambrian fuxianhuiids from China reveal origin of the gnathobasic protopodite in euarthropods. Nature Communications 9, 470.CrossRefGoogle ScholarPubMed
Zhang, XG and Pratt, BR (1996) Early Cambrian palaeoscolecid cuticles from Shaanxi, China. Journal of Paleontology 70, 275–9.CrossRefGoogle Scholar
Zhao, FC, Caron, JB, Bottjer, DJ, Hu, SX, Yin, ZJ and Zhu, MY (2014) Diversity and species abundance patterns of the early Cambrian (Series 2, Stage 3) Chengjiang Biota from China. Paleobiology 40, 50–69.CrossRefGoogle Scholar
Zhao, FC, Zhu, MY and Hu, SX (2012) Diverse responses of Cambrian organisms to sedimentary events: evidence from the Chengjiang Lagerstätte of eastern Yunnan. Acta Palaeontologica Sinica 51, 265–80 (in Chinese with English summary).Google Scholar