Advertisement

Paläontologische Zeitschrift

, 66:297 | Cite as

The proximal development in anisograptids (Graptoloidea, Anisograptidae)

  • Jörg Maletz
Article

Abstract

A model for the proximal development of anisograptids is proposed. The complex proximal development types of tri- and quadriradiate rhabdosomes are constructed by repetition of simple isograptid branching. The simple structures involved in the proximal developments indicate possibly a polyphyletic origin of biradiate graptolites.

Keywords

Ordovician Dorsal Margin Proximal Development Lateral Origin MITC 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Kurzfassung

Ein Modell zur Erklärung der Proximalstrukturen der Anisograpten wird vorgestellt. Die komplex erscheinenden Proximalstrukturen der bi-, tri- und quadriradiaten Rhabdosome werden durch die Wiederholung einer einfachen Grundregel, der isograptiden Verzweigung, hergestellt. Diese Struktur könnte einen polyphyletischen Ursprung der biradiaten Graptolithen andeuten.

References

  1. Bates, D.E.B. 1987. The construction of graptolite rhabdosomes in the light of ultrastructural studies.— Indian Journal of Geology59: 1–28, Calcutta.Google Scholar
  2. Bulman, O.M.B. 1949. A re-interpretation of the structure ofDictyonema flabelliforme Eichwald.— Geologiska Föreningen i Stockholm Förhandlingar71: 33–40, Stockholm.Google Scholar
  3. — 1950. On some Ordovician graptolite assemblages of Belgium.—Institut royal des Sciences naturelles de Belgique, Bulletin26: 1–8, Bruxelles.Google Scholar
  4. — 1970. Graptolithina with sections on Enteropneusta and Pterobranchia.—[In:] Teichert, C. (ed.) Treatise on Invertebrate Paleontology, Pt. V: I-XXXII, V1-V163, 109 figs., Geological Society of America, Boulder and Kansas University Press, Lawrence, Ka.Google Scholar
  5. Cooper, R. A. 1983. Can a graptolite have three primary stipes?—Graptolite Newsletter4: 3–4, Leicester.Google Scholar
  6. Cooper, R. A. &Fortey, R.A. 1983. Development of the graptoloid rhabdosome.—Alcheringa7: 201–221, Sydney.CrossRefGoogle Scholar
  7. Erdtmann, B.-D. 1982. A reorganization and proposed phylogenetic classification of planktonic Tre-madoc (early Ordovician) dendroid graptolites.—Norsk Geologisk Tidsskrift62: 121–145, Oslo.Google Scholar
  8. — 1988. The earliest Ordovician nematophorid graptolites: taxonomy and correlation.—Geological Magazine125: 327–348, Cambridge.Google Scholar
  9. Erdtmann, B.-D., Maletz, J., &Gutierrez Marco, J.C. 1987. The new Early Ordovician (Hunneberg Stage) graptolite genusParadelograptus (Kinnegraptidae), its phylogeny and biostratigraphy.— Paläontologische Zeitschrift61: 109–131, Stuttgart.Google Scholar
  10. Erdtmann, B.-D. &Wang Xiaofeng 1990. Evolution of proximal branching patterns in the earliest Ordovician nematophorous graptolites.—Fourth International Graptolite Conference, Nanjing 1990, China, Abstracts, Nanjing.Google Scholar
  11. Fortey R.A. &Cooper, R.A. 1986. A phylogenetic classification of the graptoloids.—Palaeontology29: 631–654, London.Google Scholar
  12. Hutt, J. E. 1974. The development ofClonograptus tenellus andAdelograptus hunnebergensis.—Lethaia7: 79–92, Oslo.CrossRefGoogle Scholar
  13. Legrand, P. 1963. Un graptolite remarquable de POrdovicien inférieur du Sahara algérienChoristograptus louhai nov. gen., nov. sp.—Bulletin de la Société géologique de France, sér. 7,5: 52–58, Paris.Google Scholar
  14. — 1964. Deux nouvelles espèces du genreAdelograptus (Graptolites) dans l’Ordovicien inférieur du Sahara algérien.—Bulletin de la Société géologique de France, sér. 7,6: 295–304, Paris.Google Scholar
  15. — 1974. Development of rhabdosomes with four primary branches in the groupDictyonema flabelliforme (Eichwald).—Special Papers in Palaeontology13: 20–34, London.Google Scholar
  16. Lin, Y.-K. 1981. New materials of graptodendroids with special reference to the classification of graptodendroids.—Bulletin of the Nanjing Institute of Geology and Palaeontology, Academia Sinica 3: 241–262, Nanjing.Google Scholar
  17. Lindholm, K. 1991. Early Hunneberg (Ordovician, La 2) graptolites from Southern Scandinavia.— Palaeontology 34: 283–327, London.Google Scholar
  18. Lindholm, K. &Maletz, J. 1989. Intraspecific variation and relationships of some Lower Ordovician species of the dichograptidClonograptus.—Palaeontology32: 711–743, London.Google Scholar
  19. Maletz, J. in press. Pendent Didymograptids (Graptoloidea, Dichograptina).—Fourth International Conference, Nanjing, of the Graptolite working group of the International Palaeontological Association, Conference volume.Google Scholar
  20. Mitchell, C.E. 1987. Evolution and phylogenetic classification of the Diplograptacea.—Palaeontology30: 353–405, London.Google Scholar
  21. Mu, E.-Z. 1974. Evolution, classification and distribution of Graptoloidea and graptodendroids.—Scientia Sinica17: 227–238, Beijing.Google Scholar
  22. Obut, A.T. &Sobolevskaja, R.F. 1962. Problemi neftegazonosti Sovjetskoj Arktiki: Paleontologija i biostratigrafija: Graptoliti rannego Ordovika na Taimyre.—Trudi Nautshno Issledowatelskogo Instituta Geologii, arkitit127: 65–85, Moscow.Google Scholar
  23. Rushton, A.W.A. 1981. A polymorphic graptolite from concealed Tremadoc rocks of England.— Geological Magazine118: 615–622, Cambridge.CrossRefGoogle Scholar
  24. Spjeldnaes, N. 1963. Some Upper Tremadocian graptolites from Norway.—Palaeontology6: 121–131, London.Google Scholar
  25. Williams, S.H. &Stevens, R.K. 1988. Early Ordovician (Arenig) graptolites of the Cow Head Group, western Newfoundland, Canada.—Palaeontographica Canadiana5: 100 pp., Toronto.Google Scholar
  26. — 1991. Late Tremadoc graptolites from Western Newfoundland.—Palaeontology34: 1–47, London.Google Scholar

Copyright information

© E. Schweizerbart’sche Verlagsbuchhandlung 1992

Authors and Affiliations

  • Jörg Maletz
    • 1
  1. 1.Institut für Geologie und PaläontologieTechnische Universität BerlinBerlin10Germany

Personalised recommendations