Talk:Olenellus

Distribution

The article is a bit misleading, implying that Olenellus is found only in North America. It is found in the UK, both in Shropshire (England) and in NW Scotland. The article cites Cowie and McNamara (1978), the modern description of Olenellus in the lower Cambrian of Scotland, but does not discuss this in the text or list the Scottish location in the distribution section. Historically this was important, as it allowed the dating of the Durness-Eriboll formation and the alignment of the earlier Torridon sandstone woth the Longnmyndian of England - see Charles Lapworth. It would be great if someone who knows more geology than I do could clarify the realtion between the Laurentian and modern geography and expand the distribution - I believe Olenellus is also found in Scandinavia and Russia: Oldroyd, David R. (1990). The Highlands Controversy. University of Chicago Press. p. 291. ISBN 0-226-62635-0.. My interest here is history of science, not geology per se. Kognos (talk) 10:03, 2 November 2020 (UTC)

It's presence in what is now Scotland makes sense as that was part of Laurentia at the time. According to the article Olenellus only existed from 522 to 510 mya, before the collisions with Baltica and Avalonia, which would make it's presence in England (Avalonia) or Scandinavia and Russia (Baltica) surprising. The PBDB Navigator doesn't show any European specimens (apart from Svalbard. Could there have been a reclassificaiton (genus split) since those references? —  Jts1882 | talk  12:26, 2 November 2020 (UTC)

Yes, at leasr two of the species used in the alignment of formations in England and Scotland have been re-assigned, O. callavei to Callavonia callavei and O. lapworthi to Fritzolenellus lapworthi. These are listed in the re-assigned species section, but there is no discussion or context for the changes, and this is very confusing for someone coming at this from a historical perspective, given that the original names were in use for over a century. I'll try to think of ways to add some context. Kognos (talk) 16:15, 8 November 2020 (UTC)

I've edited the article which I was working on, Charles Lapworth, so that it now refers to Olenelloid trilobites and links to Olenellina rather than here. Both Callavonia callavei and Fritzolenellus lapworthi are included in Olenellina, so that fixes the immediate problem, but I still think some additional context and sicussion would be helpful Kognos (talk) 11:19, 9 November 2020 (UTC)