02 July 2018


Shoreweed (Littorella uniflora) is an interesting, but rather nondescript amphibious plant. It usually occurs submerged along the shallow margins of reservoirs, lakes and pools and it is easy to miss or overlook. It is probably under recorded in South Wales. However, during prolonged dry periods in summer lakes and pools dry up and their margins recede. When this happens, large populations of Shoreweed may be revealed. Summers like the one we are experiencing this year are good times to look for this plant.
Llyn Fawr is a disused reservoir, now used mostly for recreation and fishing. It is situated under the imposing north-facing walls of Craig y Llyn, near Rhigos. As a result of the prolonged hot, dry weather we've had for  the last several weeks, the shores of the reservoir have receded significantly to expose large turfs of Shoreweed. From a distance it looks like a grassy lawn.

 Extensive turf of Shoreweed along shore of Llyn Mawr

Shoreweed doesn't flower when it is submerged, but it produces stolons that give rise to rosettes of leaves and allow the plant to build dense colonies by vegetative means. Out of water each plant may produce a single male flower and one or a few female flowers (i.e. it is monoecious). The male flower, which produce 4 stamens with long, stringy filaments, is fairly obvious. The female flowers are produced lower down on the stem (see photos below). Shoreweed is a member of the Plantain family (Plantaginaceae) and like the more common plantains it is wind pollinated.

Male and female flowers of Shoreweed (Littorella uniflora)

 The four, long stringy stamens of Shoreweed male flower

When submerged, the spongy rosettes of Shoreweed resemble those of Quillworts (e.g. Isoetes lacustris) and Water Lobelia (Lobelia dortmanna), with which it often grows. These species exhibit what is called an isoetid growth form and they share similar physiological traits too; all 3 of these species grow in Llyn Fach, the smaller lake that occurs next to Llyn Fawr under the western extension of Craig y Llyn. Unlike terrestrial plants, where the carbon dioxide for photosynthesis diffuses into the leaves from the atmosphere,  isoetids obtain most of their carbon dioxide via their roots from the muddy, lake-bottom sediments in which they grow. The carbon dioxide then diffuses from the roots to the spongy, air-filled leaves which have hollow lacunae to facilitate diffusion.

Section of Shoreweed leaf showing the network of hollow lacunae

The isoetid strategy is a remarkable example of convergent evolution, where plants that belong to unrelated taxa have evolved similar morphological and physiological traits to adapt to a particular habitat or environment. For example, Water Lobelia is a member of the Bellflower family (Campanulaceae) and is not closely related to Shoreweed while Quillworts, which are related to ferns, are not even flowering plants.

02 May 2018

Colletes Cunicularius at Whiteford Burrows

I spent some time watching a colony of Colletes Cunicularius at Whiteford 2 weeks ago.
I was curious to find out why some of the males 2 or 3 at a time, were digging at one particular place in the sand for maybe 5-10 minutes and then as if bored of doing so flew away to some other places. I took a twig and started to dig where these males had started a tiny hole. After reaching a couple of centimeters down, a fully grown and emerging bee would come out and all those observed (I dug 3 holes) were males. I concluded from these observations that the digging males had detected an emerging bee at first but then must have found out (via pheromones?) that it was a male not a female and had given up digging as a result.
I also observed some females being mated by the stronger of the fighting males. Some males would try to push the stronger males out of the way but failed. When the act was over, the male would fly away and the mated female was ignored by other males. Somehow, the female had become unreceptive.
I have attached a couple of pictures below. One shows several males waiting for a female to emerge, note the smaller male behind the bigger males on the bottom left of the picture.
Sylvie Herault


20 March 2018

Swansea Vale Sand Martin colony restored

Sean Hathaway, Environment Officer for Swansea Council, led works to restore the Sand Martin colony at Swansea Vale over the winter period. The site has been used since about 1996, the year after the holes were installed by the council when the road/embankment went in, directly opposite an eroding sand bank they previously used to nest in. This artificial urban site (which comprises three groups of holes totalling 47) was in serious risk of being completely overgrown by willows and brambles. These were cleared in October 2017 to provide the martins a clear flight path into the nest holes and to reduce the risk from predators. Further works carried out in February 2018 included the removal of old sand and debris, treatment with an insecticide to rid the nest chambers of parasites, which were then refilled with clean sand.  
Despite the freezing weather, the first Sand Martins have already arrived in the county and hopefully this urban colony will benefit from the excellent work undertaken by Sean and his team.  Excellent views of what will hopefully be a busy colony can be enjoyed from the Swansea Vale footpath at SS67589877. Also keep an eye open for Goosanders and Dippers which are also frequent here.

03 February 2018

Magnificent Micro-moths

A sneak preview of this month's BAY Bugs for anyone who doesn't get the BAY magazine!

26 January 2018

Booted Knight (Tricholoma focale)

Tricoloma focale in a conifer plantation near Rhigos (14/11/16)

I tentatively identified these fruiting bodies in 2016 as Tricholoma focale, but sent a dried specimen, some photographs and a spore print to Martyn Ainsworth in Kew for DNA sequencing. Martyn informed me today that the DNA from my samples matches that obtained from the neotype of Tricholoma focale (Heilmann-Clausen (2017): Persoonia, 38: 38-57), which is great news. Tricholoma focale is very rare in Britain and largely confined to Pine Woods in Scotland and was believed to be extinct in England and Wales There have been a few records for South Wales recently, but this is the first that has been confirmed by molecular analysis and, as such, has been accessioned into the Kew collection. It is a very notable addition the mycoflora of our conifer plantations.
Many thanks again to Martyn and his team at Kew who do an amazing job.

22 January 2018

Leopard-spotted Ginkgos

The Glamorgan Fungus Group Facebook pages recently highlighted the occurrence of the small and easily overlooked fungus Bartheletia paradoxa, which occurs on fallen leaves of the Maidenhair-tree Ginkgo biloba. As we happened to be 'sort of passing' a tree I remembered seeing in Swansea Univerity Botanic Gardens, I couldn’t resist stopping to gather a few leaves in  yesterday's downpour. Back home, once dried out, many leaves displayed an attractive leopard-spotted pattern with associated tiny fruiting bodies. 
In addition to the university tree I have only ever recorded the three other trees in the Swansea area:
Singleton Park (2.22m gbh) SS6313192143
Singleton Park (2.02m gbh) SS6294992415
St James Gardens, Swansea SS643930
If anyone knows of additonal Maidenhair-trees in our area, please do let me know and/or check for this fungus.

21 January 2018

Snakeskin Brownie

Snakeskin Brownie (Hypholoma marginatum, also known as Hypholoma dispersum) is a fairly common toadstool in local Sitka Spruce plantations although it is generally uncommon in Europe as a whole. It gets its fabulous common name from the characteristic snakeskin pattern on the stipe. Given its preferred habitat, often growing on buried wood litter or wood debris among mosses, and its characteristic morphology, it is not usually difficult to identify.
In the autumn of 2016 Hilary and I came across 3 populations of a fairly distinctive toadstool in Neath Port Talbot and Rhondda Cynon Taff composed of fruiting bodies clustered in large numbers on conifer wood debris or wood chips. All were in conifer plantations at the side of forest roads but outside the forest. A photograph of part of one population growing on Sitka wood chips in the Maerdy Plantation (RCT) is shown below.

I couldn't identify this species at the time, but after microscopic examination of specimens I was convinced that it was something in the Strophariacea, a large family of brown-spored species that includes a number of well known genera such as Stropharia, PsilocybeHypholoma, Pholiota and Kuehneromyces. Given the number of species new to Britain that have been found growing on wood mulch in the last few decades, I was excited. Eventually I contacted Martyn Ainsworth at Kew who suggested that the only way to resolve this was to look at the DNA profile of the specimens, so I sent him some photos plus dry specimens from two of the populations and a spore print. I was delighted to hear from Martyn about 2 weeks ago when he informed me that the DNA profiles indicated that the specimens were actually Snakeskin Brownie - the material has now been accessioned into the Kew collection and DNA database for future reference.
I didn't even consider Snakeskin Brownie at the time, mainly because I was so used to seeing it in its characteristic form, as shown in the upper photograph. Looking at both photographs now, I can see a resemblance that can be accommodated in terms of the enormous morphological plasticity that fungal fruiting bodies often exhibit. However, if you flick through a gallery of photographs of species in the Strophariaceae you will understand the dilemma. This also illustrates how unsafe it can be to identify some fungi from photographs, something that Martyn constantly reminds people about.
My thanks to Martyn Ainsworth and his team at Kew for resolving this.