On the relationship between the rare moss Bryum marratii Wilson and a dune aquifer

Just a short note following on from the paper last year on Bryum marratii at Whiteford. Posted here as a useful reference point. Im sure you all have the journal access but if not and you want a copy drop me an email.

https://www.tandfonline.com/doi/abs/10.1080/03736687.2018.1551591?journalCode=yjbr20

Callaghan & Farr (2019) On the relationship between the rare moss Bryum marratii Wilson and a dune aquifer, Journal of Bryology, 41:1, 59-62, DOI: 10.1080/03736687.2018.1551591

Port Eynon Point

A Fossombronia, which was widely distributed along the heavily trodden grass walkway on Port Eynon Point headland, under the microscope proved to be incurva and not the expected husnotii. This is only the third record for vc41.

Harpalejeunea new for Pembrokeshire

Matt Sutton's continued scouring of VC45 for species missed during recording for Mosses & Liverworts of Pembrokeshire has produced yet another excellent record. Harpalejeunea molleri on a rock by the Afon Tewgyll, south of Carn Meini is the first of the desiccation-sensitive trio of Aphanolejeunea, Drepanolejeunea & Harpalejeunea to be seen in Pembrokeshire.  Whilst Colura is now commonplace, the other three species remain extremely rare in the southern half of Wales, and the nearest locality for Harpalejeunea is in NE Carmarthenshire.  I checked some stretches of the Afon Tewgyll about 12 years ago, but never dreamed of Harpalejeunea!

Uskmouth

A lichen survey of the mature Hawthorn scrub surrounding the Nash Reedbeds on the Gwent Levels Wetlands Reserve provided an excellent opportunity to record bryophytes in two under-recorded tetrads - ST38G and ST38L. Both were boosted to >50 species, which is a decent total for the Levels. Recording in ST38L started at Nash Church, where the churchyard supported 48 bryophyte species including Orthotrichum stramineum, Didymodon luridus and Orthotrichum cupulatum, the last of which was new for the Gwent Levels.  Drepanocladus aduncus was abundant in damp, low-lying areas behind the seawall, and a couple of shoots of Scleropodium purum were a surprise under dense Hawthorn scrub.

Highlight of ST38L was an area of Pulverised Fly Ash mounds, which held five species of thallose liverwort - Lunularia cruciata, Marchantia polymorpha ruderalis, Aneura pinguis, Riccardia chamedryfolia and Pellia endiviifolia - alongside frequent Leptobryum pyriforme.  Lime-rich gravel held abundant Bryum sp. with unripe sporophytes and long-excurrent costas - which is probably B. caespiticium but needs a return visit - Hypnum lacunosum and Fissidens dubius, with the Fissidens being new for the Levels.  A quick scramble along the seawall at Goldcliff Point produced 15 moss species in the fragmentary tetrad ST38Q.

I have just 70 tetrads to visit to achieve complete tetrad coverage in VC35, although finishing recording by the end of 2020 seems a little far-fetched.

Zygodon rupestris

The two common Zygodons, viridissimus (var. viridissimus) and conoideus are widespread and fairly common in VC41. Roy Perry described Zygodon viridissimus as a frequent epiphyte in the county (in NPT it is also found frequently on stone). In contrast Roy described Z. conoideus as rare, but probably overlooked and confused with viridissimus. Like other epiphytes it has probably increased greatly in the last few decades. Unlike Z. viridissimus it often produces capsules in early spring, which draws your attention. Zygodon rupestris wasn't listed by Roy in the county Flora, but, if our current records are sound, it looks as if it is widespread here and probably under recorded. 

Current MapMate records for Zygodon rupestris in Glamorgan

I can't remember ever seeing Z. viridissimus with capsules, but we do occasionally find rupestris in fruit which can lead to confusion with conoideus. The Atlas warns that confusion with conoideus may have led to errors in mapped records of rupestris. So it pays to check the gemmae which in my experience are always present in these 3 species and easily found if you mash up a few leaves on a slide. Zygodon conoideus usually produces lots of gemmae which are 7 or 8 cells long while the gemmae of rupestris are 4 or 5 cells long. The gemmae of Z. viridissimus are almost bullet-shaped and, uniquely, have longitudinal and transverse cell walls.

Zygodon viridissimus: bullet-shaped gemma with longitudinal and transverse cell walls; specimen epiphytic on Sitka Spruce, Pentreclwydau

Zygodon conoideus: cigar-shaped gemma with 8 cells (no longitudinal walls); specimen epiphytic on Grey Willow, Pentreclwydau

Zygodon rupestris: gemma with 5 cells (no longitudinal walls); specimen epiphytic on mature Ash, Ynysmeudwy