Hennediella stanfordensis moving west

Hennediella stanfordensis near Pont Nedd Fechan

On Tuesday afternoon we noted a significant patch of Hennediella stanfordensis under the Pont Nedd Fechan A465 flyover (SN903807476), near to where the Mellte makes a confluence with the Nedd Fechan (and becomes the River Neath). This is new to me and may be new for VC41.
The rather neat rosettes of bluntly-rounded leaves remind me of Syntrichia latifolia, but the teeth on the upper part of the leaf, which can be (just) made out with a hand lens, are very clear under the microscope. The leaf also has a distinct point at the apex.

Teeth on upper margin of Hennediella stanfordensis leaf

Other useful leaf microscopic characters are the border of elongated cells and the clearly papillose cells.

Elongated marginal cells and papillose cells of Hennediella stanfordensis leaf

First recored in Britain in 1958, most bryologists regard H. stanfordensis as an alien although Smith made an argument for it being native. It certainly shows a distribution pattern that is typical of founder populations. This Neath Valley record certainly looks a bit disjunct from the concentration of records on the English-Welsh borders but I suspect that there is more of it in suitable areas elsewhere in Glamorgan. 

A few bits and bobs from the Usk

I had a quick walk along the Usk at Abergavenny at lunchtime on Friday and it occurred to me that I hadn’t seen Hennediella stanfordensis for some time.  Water levels were low enough to be able drop down onto rivers edge and peer at the eroding banks.   Bank erosion due to recent winter floods meant that there were relatively few areas with any bryophyte cover and it took me some time to find a few small patches of Hennediella although were some nice colonies of Bryum gemmiferum here and there.    

Not sure I have ever looked at Hennediella under the microscope – the few teeth near the leaf tips are very distinctive.

Male and female Lunularia seem frequent along this part of the Usk – in the past I have kept an eye on mixed patches, but haven’t yet seen any sporophytes.

 

Further upstream past the hospital is a stoney bank where Bryum donianum grows – I am not sure I have ever looked at donianum under the microscope either, so I pulled a couple of leaves off – in the field the thick margin joining the nerve is obvious, but the tiny teeth probably less so.    

Bonus species included a common sandpiper, presumably the same bird I had seen further upstream earlier in the week, a kingfisher and there were also a few snowdrops flowering on a nearby roadside.

Wye oh Wye?

Before the head-high Nettles and Balsam make visits to the riverbank impossible, I had a check of the silty Salix by the River Wye at Wyesham.  The results were surprisingly mundane and I couldn't find any sign of the Myrinia that I was hoping for, although Orthotrichum sprucei was abundant alongside Leskea and a bit of Dialytrichia.  I'll try to return because I only searched the upper trunks/branches of the willows briefly.

Just as I was about to give up, I noticed a very opaque-looking moss on the ground - Hennediella stanfordensis to compliment the darker green, more translucent H. macrophylla photographed in Chichester the other week.  A microscope confirmed sharp teeth near the leaf apex.