Tuesday, 3 March 2015
Tom Blockeel just returned a specimen of Ctenidium molluscum that I had collected as var. condensatum from upland crags in Brecks - a dense specimen with some long shoots and orange tinge (and fruiting). However, Tom didn't think it looked any different to var. molluscum under the microscope (and it didn't have the strongly plicate leaves of true condensatum) - Tom admits that he doesn't really understand var. condensatum and that he also sees similar large forms of C. molluscum with an orange tinge in the uplands. So what is most of the Ctenidium we see in the uplands - surely not another variety?. Over the years I have tended to avoid trying to identify Ctenidium to variety as I never felt very confident with them, but weedy looking woodland forms certainly looks very different to these upland plants. When Johnny Turner dropped a specimen of var. robustum he had collected on Mynydd Du on my desk, it at least did look different to other Ctenidium I had seen, although when I looked at a few herbarium specimens from Scotland in NMW, the Carms plant seemed much less robust. I guess we need to find and encourage an enthusiastic student to do some molecular analysis on this one.