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Macroevolutionary Patterns of the Chelicerata and Tracheata

Published online by Cambridge University Press:  17 July 2017

Bret S. Beall
Department of Geology, Field Museum of Natural History, Chicago, Illinois 60605, U.S.A.
Conrad C. Labandeira
Department of Plant Biology, University of Illinois, Urbana, Illinois 61801, U.S.A.
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Most paleontological textbooks deal with tracheates and chelicerates in only a cursory way because of their putatively poor fossil record. However, recent investigations into the paleobiology of these groups reveal that the fossil record is not only more extensive than previously assumed, but provides a wealth of information regarding both broad and detailed patterns of evolution of the two most diverse subphyla on the planet. Tracheata, including insects, entognaths and the various myriapod groups, are the most diverse subphylum. Insects alone are the most diverse class of animals known, outnumbering the combined species level diversity of all other animals. The Chelicerata, composed of the eurypterids, xiphosurids, arachnids and pycnogonids, are the second most diverse subphylum, with the diversity of arachnids exceeding all classes except for the insects. Consequently, not only does the evolution of tracheates and chelicerates provide an interesting story in itself, but these groups also provide us with insight into more general aspects of the evolutionary process that are of interest to the general evolutionary biologist as well as to the arthropod specialist.

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Copyright © 1990 Paleontological Society 

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Almond, J.E. 1985. The Silurian-Devonian fossil record of the Myriapoda. Philosophical Transactions of the Royal Society of London (B), 309:227237.CrossRefGoogle Scholar
Anderson, D.L. 1973. Embryology and Phylogeny in Annelids and Arthropods. Pergamon Press, Oxford, 495 p.Google Scholar
Beall, B.S. 1987. Parallel patterns of terrestrial floral extinction in the late Carboniferous. Geological Society of America Abstracts with Programs, 18:583.Google Scholar
Beall, B.S. 1988a. Pattern and process in arachnid evolution. Geological Society of America Abstracts with Programs, 19:A47.Google Scholar
Beall, B.S. 1988b. Phylogenetic systematics of the Arachnida. American Arachnology, 38:4.Google Scholar
Beall, B.S. 1990. Phylogeny and macroevolution within the Arachnida. Unpublished Ph.D. thesis, University of Michigan, 334 p.Google Scholar
Bergström, J. 1975. Functional morphology and evolution of xiphosurids. Fossils and Strata, 4:291305.Google Scholar
Bergström, J. 1979. Morphology of fossil arthropods as a guide to phylogenetic relationships, p. 356. In Gupta, A.P. (ed.), Arthropod Phylogeny. Van Nostrand Reinhold Company; New York.Google Scholar
Bernini, F. 1986. Current ideas on the phylogeny and the adaptive radiations of Acarida. Bolletino di Zoologico, 53:279313.CrossRefGoogle Scholar
Boudreaux, H.B. 1987. Arthropod Phylogeny with special reference to Insects. Robert E. Krieger, Malabar (Florida), 320 p.Google Scholar
Briggs, D.E.G., Bruton, D.L., and Whittington, H.B. 1979. Appendages of the arthropod Aglaspis spinifer, Upper Cambrian, Wisconsin, and their significance. Palaeontology, 22:167180.Google Scholar
Briggs, D.E.G., and Collins, D. 1988. A Middle Cambrian chelicerate from Mount Stephen, British Columbia. Palaeontology, 31:779798.Google Scholar
Burnham, L. 1983. Studies on Upper Carboniferous insects: 1. The Geraridae (order Prothoptera). Psyche, 90:157.Google Scholar
Carpenter, F.M. 1954. Classification of fossil insects. Bulletin of the Museum of Comparative Zoology, 108:777827.Google Scholar
Carpenter, F.M. 1963. Studies on Carboniferous insects from Commentry, France, Part IV: the genus Triplosoba . Psyche, 70:120128.CrossRefGoogle Scholar
Carpenter, F.M. 1966. The Lower Permian insects of Kansas, Part 11. Psyche, 73:4688.CrossRefGoogle Scholar
Carpenter, F.M. in preparation. Hexapoda: Classes Collembola, Protura, Diplura, Insecta. In Treatise on Invertebrate Paleontology. Geological Society of America, Lawrence (Kansas).Google Scholar
Carpenter, F.M., and Burnham, L. 1985. The geological record of insects. Annual Review of Earth and Planetary Sciences, 13:297314.CrossRefGoogle Scholar
Caster, K.E., and Brooks, H.K. 1956. New fossils from the Canadian-Chazyan (Ordovician) hiatus in Tennessee. Bulletin of American Paleontology, 36:157199.Google Scholar
Cisne, J.L. 1973. Anatomy of Triarthrus and the relationships of the Trilobita. Fossils and Strata, 4:4563.Google Scholar
Crowson, R.A. 1985. Comments on Insecta of the Rhynie Chert. Entomologica Generales, 11:9798.CrossRefGoogle Scholar
De Beer, G. 1958. Embryos and Ancestors. Clarendon Press, Oxford, 192 p.Google Scholar
Dohle, W. 1980. Sind die Myriapoden eine monophyletische Gruppe? Abhandlung der Naturwissenshaften Vereinigen des Hamburg, Neue Folge, 23:45104.Google Scholar
Eldredge, N. 1974. Revision of the suborder Synziphosurina (Chelicerata, Merostomata), with remarks on merostome phylogeny. American Museum Novitates, (2543):141.Google Scholar
Eldredge, N., and Plotnick, R.E. 1974. Revision of the pseudoniscine merostome genus Cyamocephalus Currie. American Museum Novitates, 2557:110.Google Scholar
Ferris, G.F. 1942. Some observations on the head of insects. Microentomology, 7:2562.Google Scholar
Firstman, B. 1973. The relationship of the chelicerate arterial system to the evolution of the endosternite. Journal of Arachnology, 1:154.Google Scholar
Fisher, D.C. 1975a. Evolution and functional morphology of the Xiphosurida. Unpublished Ph.D. thesis, Harvard University, 391 p.Google Scholar
Fisher, D.C. 1975b. Swimming and burrowing in Limulus and Mesolimulus. Fossils and Strata, 4:281290.Google Scholar
Fisher, D.C. 1981. The role of functional analysis in phylogenetic inference: examples from the history of the Xiphosura. American Zoologist, 21:4762.CrossRefGoogle Scholar
Fisher, D.C. 1982. Phylogenetic and macroevolutionary patterns within the Xiphosurida. Third North American Paleontological Convention, Proceedings, I:175180.Google Scholar
Fisher, D.C. 1984. The Xiphosurida: Archetypes of Bradytely? p. 196217. In Eldredge, N. and Stanley, S.M. (eds.), Living Fossils. Springer-Verlag, New York.CrossRefGoogle Scholar
Fisher, D.C. 1986. Progress in organismal design, p. 99117. In Raup, D.M. and Jablonski, D. (eds.), Patterns and processes in the history of life. Springer-Verlag, Berlin, Heidelberg.CrossRefGoogle Scholar
Gingerich, P.D. 1979. Stratophenetic approach to phylogeny reconstruction in vertebrate paleontology, p. 4177. In Cracraft, J. and Eldredge, N. (eds.), Phylogenetic analysis and paleontology. Columbia University Press, New York.Google Scholar
Goldschmidt, R. 1940. The material basis of evolution. Yale University Press, New Haven, 152 p.Google Scholar
Gould, S.J. 1977. Ontogeny and phylogeny. Belknap Press, Cambridge, Massachusetts, 501 p.Google Scholar
Grasshoff, M. 1978. A model of the evolution of the main chelicerate groups. Symposium of the Zoological Society of London, 42:273284.Google Scholar
Greenslade, P.J.M. 1988. Reply to R. A. Crowson's “Comments on Insecta of the Rhynie Chert” (1985 Entomologica Generalis ll[1/2]:97-98). Entomologica Generalis, 13:115117.CrossRefGoogle Scholar
Greenslade, P.J.M., and Whalley, P.E.S. 1986. The systematic position of Rhyniella praecursor Hirst & Maulik (Collembola), the earliest known hexapod, p. 319323. In Dallai, R. (ed.), Proceedings of the Second Seminar on the Apterygota. University of Siena Press, Siena, Italy.Google Scholar
Hammen, L. Van Der. 1963. The addition of segments during the postembryonic ontogenesis of the Actinotrichida (Acarida) and its importance for the recognition of the primary subdivision of the body and the segmentation. Acarologia, 5:441454.Google Scholar
Hammen, L. Van Der. 1970a. La segmentation des appendices chez les acariens. Acarologia, XII:1115.Google Scholar
Hammen, L. Van Der. 1970b. La segmentation primitive des acariens. Acarologia, XII:110.Google Scholar
Hammen, L. Van Der. 1971. Classification and phylogeny of mites. Proceedings of the Third International Congress of Acarology, Prague:275282.Google Scholar
Hammen, L. Van Der. 1974. Evolution in mites, and the patterns of evolution in Arachnidea. Proceedings of the Fourth International Congress of Acarology:425430.Google Scholar
Hammen, L. Van Der. 1977a. The evolution of the coxa in mites and other groups of Chelicerata. Acarologia, 19(1):1219.Google Scholar
Hammen, L. Van Der. 1977b. A new classification of Chelicerata. Zoologische Mededelingen, 51(20):307319.Google Scholar
Hammen, L. Van Der. 1978. The evolution of the chelicerate life-cycle. Acta Biotheoretica, 27(1/2):4460.CrossRefGoogle Scholar
Hammen, L. Van Der. 1979. Comparative studies in Chelicerata I: the Cryptognomae (Ricinulei, Architarbi and Anactinotrichida). Zoologische Verhandelingen, 174:162.Google Scholar
Hammen, L. Van Der. 1981. Numerical changes and evolution in actinotrichid mites (Chelicerata). Zoologische Verhandelingen, 182:147.Google Scholar
Hammen, L. Van Der. 1982. Comparative studies in Chelicerata II: Epimerata (Palpigradi and Actinotrichida). Zoologische Verhandelingen, 196:170.Google Scholar
Hammen, L. Van Der. 1985a. Comparative studies in Chelicerata III: Opilionida. Zoologische Verhandelingen, 220:160.Google Scholar
Hammen, L. Van Der. 1985b. Functional morphology and affinities of extant Chelicerata in evolutionary perspective. Transactions of the Royal Society of Edinburgh, 76:137146.CrossRefGoogle Scholar
Hammen, L. Van Der. 1987. Comparative studies in Chelicerata IV: Apatellata, Arachnida, Scorpionida, Xiphosura. Zoologische Verhandelingen, 226:152.Google Scholar
Handlirsch, A. 1906-1908. Die Fossilen Insekten und die Phylogenie der Rezenten Formen. Wilhelm Engelmann, Leipzig, 1430 p.Google Scholar
Harland, W.B., Cox, A.V., Llewellyn, P.G., Pickton, C.A.G., Smith, A.G., and Walters, R. 1982. A geologic time scale. Cambridge University Press, Cambridge, 131 p.Google Scholar
Hennig, W. 1966. Phylogenetic Systematics. University of Illinois Press, Urbana, 263 p.Google Scholar
Hesselbo, S.P. 1988. Trace fossils of Cambrian aglaspid arthropods. Lethaia, 21:139146.CrossRefGoogle Scholar
Hesselbo, S.P., and Maulik, S. 1926. On some arthropod remains from the Rhynie Chert (Old Red Sandstone). Geological Magazine, 63:6971.Google Scholar
Jamieson, B.G.M. 1987. The Ultrastructure and Phylogeny of Insect Spermatozoa. Cambridge University Press, Cambridge, 320 p.Google Scholar
Keilbach, R. 1982. Bibliographie und Liste der Arten tierischer Einschlüsse in fossilen Harzen sowie ihrer Aufbewahrungsorte. Deutsche Entomologische Zeitschrift (Neue Folge), 29:129286.CrossRefGoogle Scholar
Kevan, P.G., Chaloner, W.G., and Savile, D.B.O. 1975. Interrelationships of early terrestrial arthropods and plants. Palaeontology, 18:391417.Google Scholar
Kopaska-Merkel, D.C. 1988. Trace-fossil frequency modes and arthropod growth. Northeastern Geology, 10:300306.Google Scholar
Krantz, G.W., and Lindquist, E.E. 1979. Evolution of phytophagous mites (Acari). Annual Review of Entomology, 24:121158.CrossRefGoogle Scholar
Kristensen, N.P. 1981. Phylogeny of the insect orders. Annual Review of Entomology, 26:135157.CrossRefGoogle Scholar
Kukalova-Peck, J. 1987. New Carboniferous Diplura, Monura, Thysanura, the hexapod ground plan, and the role of thoracic side lobes in the origin of wings (Insecta). Canadian Journal of Zoology, 26:135157.Google Scholar
Labandeira, C.C., Beall, B.S., and Hueber, F.M. 1988a. Description and systematic assignment of a Lower Devonian (Lower Emsian) insect from Gaspé Peninsula, Quebec, Canada. International Entomological Congress (Vancouver) Proceedings, 18:45.Google Scholar
Labandeira, C.C., Beall, B.S., and Hueber, F.M. 1988b. Early insect diversification: evidence from a Lower Devonian bristletail from Quebec. Science, 242:913916.CrossRefGoogle Scholar
Labandeira, C.C., Beall, B.S., and Hueber, F.M. 1988c. Structure and inferred life-habits of an early Devonian bristletail: what does the earliest insect tell us about the origin of insects? Geological Society of America Abstracts with Programs, 19:A47.Google Scholar
Lankester, E.R. 1904. The structure and classification of the Arthropoda. The Quarterly Journal of Microscopical Science, 47:523547.Google Scholar
Lankester, E.R., Benham, W.B.S., and Beck, E.J. 1885. On the muscular and endoskeletal systems of Limulus and Scorpio; with some notes on the anatomy and generic characters of scorpions. Zoological Society of London Transactions, 11:311384.CrossRefGoogle Scholar
Lauterbach, K.-E. 1973. Schlüsselereignisse in der Evolution der Stammgruppe der Euarthropoda. Zoologische Beiträge (Neue Folge), 19:251299.Google Scholar
Levi, H.W. 1967. Adaptations of respiratory systems of spiders. Evolution, 21:571583.Google ScholarPubMed
Lindquist, E.E. 1984. Current theories on the evolution of major groups of Acari and on their relationships with other groups of Arachnida, with consequent implications for their classification. Acarology, VI(1):2862.Google Scholar
Manton, S.M. 1934. On the embryology of the crustacean Nebalia bipes . Philosophical Transactions of the Royal Society of London (B), 223:163238.CrossRefGoogle Scholar
Manton, S.M. 1973. The evolution of arthropodan locomotory mechanisms. Part 11. Habits, morphology and evolution of the Uniramia (Onychophora, Myriapoda, Hexapoda) and comparisons with the Arachnida, together with a functional review of uniramian musculature. Zoological Journal of the Linnean Society, 53:257375.Google Scholar
Martynov, A.B. 1938a. Studies on the geologic history and the phylogeny of the orders of insects (Pterygota), First Part: Palaeoptera and Neoptera — Polyneoptera. Transactions of the Paleontological Institute, 7:1150.Google Scholar
Martynov, A.B. 1938b. On a new Permian order of orthopteroid insects, Glosselytrodea. Bulletin of the Academy of Sciences, USSR, Biology Series, 1938:157206.Google Scholar
Matsuda, R. 1965. Morphology and evolution of the insect head. Memoirs of the American Entomological Institute, 4:1334.Google Scholar
Mayr, E. 1982. Systematics and the origin of species. Columbia University Press, New York, 334 p.Google Scholar
Moore, R.C., Lalicker, C.G., and Fischer, A.G. 1952. Invertebrate Fossils. McGraw-Hill Book Company, Inc., New York, 766 p.Google Scholar
O'Connell, M. 1916. The habitat of the eurypterids. Buffalo Society of Natural Science Bulletin, 11:1277.Google Scholar
Petrunkevitch, A. 1913. A monograph of the terrestrial Palaeozoic Arachnida of North America. Connecticut Academy of Arts and Sciences Transactions, 18:1137.Google Scholar
Petrunkevitch, A. 1952a. Macroevolution and the fossil record of Arachnida. American Scientist, 40:99122.Google Scholar
Petrunkevitch, A. 1952b. Principles of classification as illustrated by studies of Arachnida. Systematic Zoology, 2:119.CrossRefGoogle Scholar
Petrunkevitch, A. 1953. Paleozoic and Mesozoic Arachnida of Europe. Geological Society of America Memoirs, 53:1128.CrossRefGoogle Scholar
Petrunkevitch, A. 1954. Status of invertebrate paleontology, 1953:IX. Macroevolution and the problem of missing links. Bulletin of the Museum of Comparative Zoology at Harvard College, 112:239258.Google Scholar
Petrunkevitch, A. 1955a. Arachnida. p. 42162. In Moore, R.C. (ed.), Treatise on Invertebrate Paleontology, Part P (Arthropoda 2). Geological Society of America and University of Kansas Press; Lawrence.Google Scholar
Platnick, N.I. 1977. Cladograms, phylogenetic trees, and hypothesis testing. Systematic Zoology, 26:438442.CrossRefGoogle Scholar
Platnick, N.I., and Nelson, G.J. 1978. A model of analysis for historical biogeography. Systematic Zoology, 27:116.CrossRefGoogle Scholar
Plotnick, R.E. 1983. Patterns in the evolution of the eurypterids. Unpublished Ph.D. thesis, University of Chicago, 411 p.Google Scholar
Plotnick, R.E. 1985. Life based mechanisms for swimming in eurypterids and portunid crabs. Transactions of the Royal Society of Edinburgh, Earth Sciences, 76:325337.CrossRefGoogle Scholar
Plotnick, R.E., and Baumiller, T. 1987. The pterygotid telson as a biological rudder. Lethaia, 21:1327.CrossRefGoogle Scholar
Raasch, G. 1939. Cambrian Merostomata. Geological Society of America Special Publication, 19:1146.Google Scholar
Raw, F. 1957. Origin of chelicerates. Journal of Paleontology, 31:139192.Google Scholar
Retallack, G.J., and Feakes, C.R. 1987. Trace fossil evidence for Late Ordovician animals on land. Science, 235:6163.CrossRefGoogle ScholarPubMed
Riek, E.F. 1976. An entomobryid collembolan (Hexapoda: Collembola) from the Lower Permian of Southern Africa. Palaeontologica Africana, 19:141143.Google Scholar
Robison, R.A. 1990. Earliest-known uniramous arthropod. Nature, 343:163164.CrossRefGoogle Scholar
Rohdendorf, B.B., and Rasnitsyn, A.P. (eds.). 1980. Historical development of the Class Insecta. Transactions of the Paleontological Institute 175:1269. [in Russian] Google Scholar
Savory, T. 1971. Evolution in the Arachnida. Merrow Publishing Co. Ltd., New York, 42 p.Google Scholar
Savory, T. 1974. On the arachnid order Palpigradi. Journal of Arachnology, 2:4345.Google Scholar
Schaller, F. 1979. Indirect sperm transfer by soil arthropods. Annual Review of Entomology, 16:407446.CrossRefGoogle Scholar
Schneider, J. 1977. Zur Variabilitat der Flügel palaeozoischer Blattodea (Insecta), Teil I. Freiberger Forschungsheft (C), 326:87105.Google Scholar
Scourfield, D.J. 1940. The oldest known fossil insect (Rhyniella praecursor Hirst & Maulik) – further details from additional specimens. Proceedings of the Linnean Society of London, 152:113131.CrossRefGoogle Scholar
Selden, P.A. 1981. Functional morphology of the prosoma of Baltoeurypterus tetragonophthalmus (Fischer). Transactions of the Royal Society of Edinburgh: Earth Sciences, 72:948.CrossRefGoogle Scholar
Selden, P.A. 1988. The arachnid fossil record. British Journal of Entomology and Natural History, 1:1518.Google Scholar
Selden, P.A., and Siveter, D.J. 1988. The origin of the limuloids. Lethaia 20:383392.CrossRefGoogle Scholar
Sharov, A.G. 1957. Peculiar Paleozoic wingless insects of the new order Monura. Doklady, Academia Alauk USSR 115:796798. [in Russian] Google Scholar
Sharov, A.G. 1966. Basic Arthropodan Stock. Pergamon Press, Oxford, 271 p.Google Scholar
Sharov, A.G. 1971. Phylogeny of the Orthopteroidea. Program for Scientific Translation, Jerusalem (Israel), 251 p.Google Scholar
Shear, W.A. 1989. Sanctacaris: the oldest chelicerate? American Arachnology, 42:3.Google Scholar
Shear, W.A., Bonamo, P.M., Grierson, J.D., Rolfe, W.D.I., Smith, E.L., and Norton, R.A. 1984. Early land animals in North America: evidence from Devonian age arthropods from Gilboa, New York. Science, 224:492494.CrossRefGoogle ScholarPubMed
Shear, W.A., Selden, P.A., Rolfe, W.D.I., Bonamo, P.M., and Grierson, J.D. 1987. New terrestrial arachnids from the Devonian of Gilboa, New York (Arachnida, Trigonotarbida). American Museum Novitates, (2901):174.Google Scholar
Simpson, G.G. 1944. Tempo and mode in evolution. Columbia University Press, New York, 237 p.Google Scholar
Snodgrass, R.E. 1935. Principles of Insect Morphology. McGraw-Hill Book Co., New York, 667 p.Google Scholar
Stanley, S.M. 1973. An explanation for Cope's rule. Evolution, 27:126.CrossRefGoogle ScholarPubMed
Størmer, L. 1933. Are the trilobites related to the arachnids? American Journal of Science, 26:147157.CrossRefGoogle Scholar
Størmer, L. 1944. On the relationships and phylogeny of fossil and Recent Arachnomorpha: a comparative study on Arachnida, Xiphosure, Eurypterida, Trilobita, and other fossil Arthropoda. Skrifter utgitt av det Norske Videnskaps-Akademi i Oslo, I, Matematisknaturvidenskabelig Klasse, 5:1158.Google Scholar
Størmer, L. 1952. Phylogeny and taxonomy of fossil horseshoe crabs. Journal of Paleontology, 26:630639.Google Scholar
Størmer, L. 1955. Merostomata. p. 441. In Moore, R.C. (ed.), Treatise on Invertebrate Paleontology, Part P (Arthropoda 2), Lawrence: Geological Society of America and University of Kansas Press.Google Scholar
Swofford, D.L. 1985. Phylogenetic Analysis Using Parsimony (Version 2.4). Illinois Natural History Survey, Champaign, Illinois, 104 p.Google Scholar
Tiegs, O.W., and Manton, S.M. 1958. The evolution of the Arthropoda. Biological Review, 33:255337.CrossRefGoogle Scholar
Tillyard, R.J. 1931. Kansas Permian insects. Part 13. The new order Protelytroptera, with a discussion of its relationships. American Journal of Science, 21:232266.CrossRefGoogle Scholar
Weygoldt, P., and Paulus, H.F. 1979. Untersuchungen zur Morphologie, Taxonomie und Phylogenie der Chelicerata. II. Cladogramme und die Entfaltung der Chelicerata. Zeitschrift für Zoologische Systematik und Evolutionsforschung, 17:177200.CrossRefGoogle Scholar
Whalley, P., and Jarzembowski, E.A. 1981. A new assessment of Rhyniella, the earliest known insect, from the Devonian of Rhynie, Scotland. Nature, 291:317.CrossRefGoogle Scholar
Wootton, R.J. 1981. Palaeozoic insects. Annual Review of Entomology, 26:319344.CrossRefGoogle Scholar
Yoshikura, M. 1965. Postembryonic development of a whip-scorpion, Typopeltis stimpsonii (Wood). Kumamoto Journal of Science (B) (Sec. 2), 7(2):2151.Google Scholar
Yoshikura, M. 1975. Comparative embryology and phylogeny of Arachnida. Kumamoto Journal of Science, Biology, 12:71142.Google Scholar

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