Paläontologische Zeitschrift

, Volume 58, Issue 3–4, pp 197–209 | Cite as

Lapworthella filigrana n.sp. (incertae sedis) from the Lower Cambrian of the Cassiar Mountains, northern British Columbia, Canada, with comments on possible levels of competition in the early Cambrian

  • S. Conway Morris
  • W. H. Fritz


Two samples from the base of the Rosella Formation(Nevadella Zone) in the Cassiar Mountains, British Columbia, yielded a new species of the enigmatic genusLapworthella, L. filigrana n. sp., that is characterized by denticulate growth ridges and ornamented inter-ridge areas. As with other species ofLapworthella, intra-specific variation is considerable. One variant is comparable toL. lucida Meshkova 1969, from northern Siberia, but shows differences in the ornamentation of the more apical inter-ridge areas. The high degree of morphological variation inLapworthella finds parallels in certain other Lower Cambrian organisms. This variability may be the result of a low level of competition rather than a previous proposal of a primitive and inefficient genetic mechanism.


Cambrian Apical Region Siberian Platform Lower Cambrian Growth Line 
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.


Zwei Proben von der Basis der Rosella-Formation(Nevadella- Zone) in den Cassiar Mountains, British Columbia, lieferten eine neue Art des rätselhaften GenusLapworthella, L. filigrana n. sp., die durch gezähnelte Anwachsleisten und ornamentierte Zwischenräume gekennzeichnet ist. Wie bei anderenLapworthella- Arten ist die intraspezifische Variabilität beträchtlich. Eine Variante läßt sich mitL. lucida Meshkova 1969 vergleichen, unterscheidet sich aber in der Skulptur der apex-nahen Leisten-zwischenräume. Die starke Variabilität vonLapworthella hat ihre Parallelen bei manchen anderen unter-kambrischen Organismen. Sie dürfte eher das Ergebnis nur geringen Konkurrenzkampfes sein als die auch schon angenommene Folge noch primitiver und uneffizienter genetischer Mechanismen.


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Copyright information

© E. Schweizerbart’sche Verlagsbuchhandlung 1984

Authors and Affiliations

  • S. Conway Morris
    • 1
  • W. H. Fritz
    • 2
  1. 1.Department of Earth SciencesCambridge UniversityCambridgeEngland
  2. 2.Geological Survey of CanadaOttawa, OntarioCanada

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