Ceratodon purpureus

Found on a thatched roof in Dorset this bryophyte I first thought was Dicranoweissia cirrata but it had dentate leaf tips. Because of this Bryoerythrophyllum recurvirostrum was considered but this species has papillose leaf cells and doesn't grow on thatched rooves. After consulting experts it was discovered that this species was indeed Ceratodon purpureus. The leaf state when dry prevented me from keying out correctly.

Ceratodon purpureus wet

Ceratodon purpureus dry

Ceratodon purpureus leaf

Ceratodon purpureus leaf section

Ephemeral mosses

I found some small ephemeral bryophytes on a reservoir bank on the weekend. The options were: Pseudephemerum, Ephemerum, Archidium and Pleuridium. I found the key to separate these not that great so have put a few notes here. Pleuridium stands out from the others by having a wide base to the leaf sharply narrowing to a mostly long needle like leaf. Archidium should have non fertile shoots with short sharply pointed leaves, quite distinctive when familiar with. This leaves separating Pseudephmerum and Ephemerum. Pseudephemerum has costate and untoothed leaves whereas the most common Ephemerum (minutissimum) has dentate leaves with no costa. Some of the more uncommon Ephemerum are costate and without maginal teeth. Perhaps only E.recurvifolium with its oblique apiculus of the capsule can be done in the field. Separating the rest may depend on the amount of magnification you have as these plants are tiny. Ephemerum sessile for example can be separated from P.nitidum by spore size; 20-32µm in P.nitidum and 60-80µm in E.sessile. The leaves look longer and thinner on E.sessile compared to P.nitidum so I suspect familiarity with these groups could be useful in the field.

Pseudephemerum nitidum

Ephemerum minutissimum showing the dentate leaf

Camilla atrimana

Plumose arista with long rays above and very short rays below, crossed P bristles and a spine on the ventral side of the fore femur should get you to Camillidae. Only about 5 species on the British list. This one shows a pointed apical section of the wing which suggests C.atrimana. C.acutipennis looks to be lumped with C.atrimana. Caught in Somerset at Crook Peak on 6/9/18

Camilla atrimana

Camilla atrimana

Camilla atrimana

Campsicnemus curvipes

Uniserial acrosticals, dorsal arista, frons narrowing towards the antennae and then widening below are some of the signs to identify Campsicnemus.

Campsicnemus curvipes

Campsicnemus curvipes

Campsicnemus curvipes

Priocnemis fennica

Found at Westhay Moor NNR on 19th August 2018. Identified as the spider hunter Priocnemis fennica.

Priocnemis fennica

Priocnemis fennica

Priocnemis fennica

Priocnemis fennica tarsal claw

Stigmella oxyacanthella

Mines of Stigmella oxyacanthella found in Sand Point NT car park on Hawthorn on 27th August 2018.

Stigmella oxyacanthella mine on Hawthorn

Didymodon tophaceus

This is one I found this morning on the coast. Under the microscope the leaves look distinctive having the shape similar to a Zygodon with the costa being in a channel. I eventually identified it as either Didymodon luridus or Didymodon tophaceus. It was a bit of a tough call but eventually I went with Didymodon tophaceus because of the leaf shape and the habit of the leaves when dry as D.luridus has appressed leaves when dry and D.tophaceus has it leaves incurled and slightly twisted.

Didymodon tophaceus

Didymodon tophaceus leaf

Didymodon fallax

Keyed this one out as Didymodon fallax and comparing photos on the internet it looks OK. Here are shots of it in wet and dry state.

Didymodon fallax dry

Didymodon fallax wet

Rhynchostegium murale

A species found most commonly on rock with deeply concave leaves. Often fertile with a subulate beak and smooth seta.

Rhynchostegium murale

Cirriphyllum crassinervium or Rhynchostegium confertum

An expert bryologist ID'd a plant for me as being C.crassinervium yesterday but upon checking it the next day I couldn't make out the dinner plate shaped leaves and the basal half of the costa was not thick. Running it through the key I notice that Cirriphyllum has strongly papillose setae which mine didn't plus the lid was subulate and not rostrate. Eventually the key ran me to Rhynchostegium and it quickly became apparent that my specimen was in fact Rhynchostegium confertum.

Rhynchostegium confertum

Didymodon vinealis

Growing on a stone on a wooded slope made Didymodon vinealis a suitable candidate for this one. The lower leaves were darker than the upper and when dry they looked appressed to the stem. Under the microscope the cells over the costa in the upper part of the leaf were quadrate.

Didymodon vinealis

Dicranodontium denudatum

Here's a species that is potentially overlooked and at first site you could be forgiven for thinking this is Dicranella heteromalla. It's not mentioned in the book as a similar species but that's exactly what it was called by an expert bryologist until he got it under the microscope. A distinguishing feature is the deciduous shoots but when absent it can hamper a safe ID. Under the microscope the basal cells will help separate D.denudatum from Dicranella heteromalla.

Dicranodontium denudatum

Scleropodium tourettii or Cirriphyllum crassinervium

This was an interesting one as this sample was identified in the field by a professional bryologist as Cirriphyllum crassinervium so in theory it should have been straight forward to key out. However, after running through the key it became apparent that it doesn't key to Cirriphyllum crassinervium. The leaf tip was the first problem being obtuse and not abruptly contracting to leave a short apiculus. This avenue led me then to chose between Rhynchostegium and Scleropodium. The key says that Scleropodium has differing sizes in stem and branch leaves whereas Rhynchostegium has them all the same size. I could see varying leaf sizes so opted for Scleropodium. This group only has two species which can be separated by habit when wet and dry plus S.tourettii has much more concave leaves than S.cespitans looking more like Pseudoscleropodium purum. This species can be eliminated by the long pinnate growth unlike the bushy matted like habit of S.tourettii. So we have an ID but look again the the thick costa in the basal half, this is typical of C.crassinervium and with the concave leaves with the flattened border we find out that it is C.crassinervium after all. As a postscript it is worth mentioning that Rhynchostegium murale is a similar looking plant and should be considered when identifying in the field perhaps.

Cirriphyllum crassinervium

Rhynchostegiella pumila

My biggest weakness in bryophytes is pleurocarps currently so thought I'd start to tackle this group. The first one wasn't easy and having three names didn't help matters either, the other two being Eurhynchium pumilum and Oxyrrhynchium pumilum.
Working through the keys down all uncertain avenues brought me to Scorpiurium circinatum, Amblystegium serpens, Conardia compacta and Oxyrrhynchium hians/speciosum. The two Oxyrrhynchium species were eliminated by their cell length. both are 40µm long whereas mine was only half that. Scorpiurium was ruled out straight away with S.circinatum have appress leaves when dry and not only this both plants look completely different. Amblystegium serpens was ruled out by having a longer narrower leaf shape. Conardia compacta looks quite close but this species has a costa that runs almost to the leaf tip and rhizoidal growth from the back of the costa.

Rhynchostegiella pumila

Rhynchostegiella pumila through the microscope

Hygrohypnum ochraceum

At first glance you'd be forgiven for thinking you've found a Hypnum but on closer inspection the presence of a costa is revealed and in this case a forked costa that runs a little over 50% of the leaf. Keying out can be misleading as the stumbling block comes when judging the costa length; if 50% or more you are taken down the wrong part of the key. Once you are aware of this Hygrohypnum becomes the obvious choice. Hygrophypnum ochraceum is tricky to separate from H.luridum in the field but under the compound microscope the presence of inflated colourless alar cells confirms Hygrophynum ochraceum.

Hygrophypnum ochraceum

Orthotrichum

Orthotrichum mosses are best identified when bearing capsules but as an exercise I decided to have a go at this one and see how far it could be narrowed down. Firstly Orthotrichums on trees can be characterised by their recurved leaf margins sometimes the entire length of the leaf. In the photo below you can see that the leaf tips are quite distinctive too beyond the recurved margin and the nerve is protruding which is also visible in the leaf section in the inset. With the specimen below the leaves were wide spreading with the basal quater curving and the remainder straight.
Elimination: O.anomalum, O.cupulatum, O.rupestre were all eliminated because they grow on rock and mine was on a branch. O.pulchellum has the leaves twisted when dry and O.tenellum has the leave flexuose when dry so these were eliminated too. O.diaphanum has a white hair point so not that one. Others were ruled out on leaf shape and Lyellii due to lack of gemmae. We are now left with a choice of three: O.stramineum, O.affine and O.striatum.

Orthotrichum affine found nearby the mystery Orthotrichum

Orthotricum sp.

Parmotrema reticulatum

Always seem to struggle with foliose lichen so the best way to get good at them is to keep trying. First clues were with UV and chemical tests. There was a faint UV+ purple, C- and K+ yellow turning red. Visually the upper surface showed many fine cracks showing the white medulla and the underside was mainly black with brown lobe tips. The rhizines present are simple and fading towards the lobe margins but the lobe tips had some sparse simple rhizines. Overall this was enough information to key out this foliose lichen to Parmotrema reticulatum.

Parmotrema reticulatum underside of lobe

Parmotrema reticulatum upper side of lobe

Fuscidea lightfootii

Found this morning on a wooden gate. Only a single simple spore was found with 1µm epispore measuring 10x7.5µm not enough to to be certain of identity. If this was a typical spore then Lecidella elaeochroma f soralifera a contender but tests show it to be something else. The thallus was UV+ white and C- suggesting something more like perhaps Fuscidea lightfootii. However, when performing a second section on a younger looking apothecia I found multiple dumbel shaped spores which were typical of Fuscidea lightfootii measuring 8x3.5µm

Fuscidea lightfootii

Rhizocarpon lavatum?

It doesn't take much effort to determine a Rhizocarpon but getting to species level is a lot more difficult. This one wouldn't key out so I instead went with the closest match. No idea what the difference between muriform, submuriform and eumuriform is and no explanation in the book. Perhaps it would have been easier to reach an ID had I have known. I've put the details here to come back in time and re-evaluate:

Spores: muriform (or could be submuriform or eumuriform) 25x11.25µm turning brown when mature.
Ascus: 120µm
hypothecium: brown
hymenium: colourless
epithecium: brown
apothecia: 0.8mm
habitat: siliceous rocks near stream

Pos Rhizocarpon lavatum

Caloplaca from Brecon Beacons 25th March

Found on 25th March 2016 on a gate post this Caloplaca was not found to be identifiable with my level of expertise currently. A shortlist was drawn up using apothecia size (1mm) and habitat giving Caloplaca citrina as the best guess. Both the thallus and apothecia are K+ purple eliminating C. virescens and C.cerina. Apothecia colour elimnated herbidella. There were few polaricula spores the largest measured 15x4.5µm. Some of the paraphyses had swollen tips measuring 3.75µm