Monday 11 January 2016

Radyr Quarry revisited

In fading light yesterday afternoon I finally managed a follow up visit to Radyr Quarry, having looked at the southern end of the quarry face in December (see here). I only managed to access a relatively small area at the northern end and this was similar in character to what I found before, with quite a bit of Leiocolea turbinata on soil-capped ledges and a few small patches of Eucladium verticillatum. Only two additional taxa were found, Trichostomum crispulum (which was common) and a Conocephalum species. I've only seen C. conicum in my local area but this patch had a distinct salebrosum look to it. The thallus has distinct grooves on the dorsal surface, as seen in the photos below. 


I wasn't 100% sure from this feature alone, so I also checked the hyaline cells at the thallus margin which, according to the Szweykowski et al. paper which first separated the two species (available here), should be 1-2 rows wide in conicum and 3-4 rows wide in salebrosum. In the photo below (click to enlarge) they are mostly 2 cells wide.
 

So this does appear to be salebrosum, though I'd like to have some fresh conicum to hand for comparison. As far as I know all the previous VC41 records since these species were split in 2005 have been from northern NPT, RCT and Merthyr Tydfil, so this site would be a bit of an outlier.

George, seems you are still missing some records from your version. Updated maps of Conocephalum taxa as follows:

2 comments:

  1. I've not checked what Paton says, but the upper leaf images look good for salebrosum and the habitat certainly sounds good for that species

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  2. Thanks for the maps Barry - I'd forgotten our email discussion before Christmas which revealed I'm still missing c. 30,000 records from my system. Not such an outlier then.

    Unfortunately Paton doesn't have anything to say on the subject as it was written pre-split.

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