|Sussex Teloschistes chrysophthalmus|
· In 1994, it had been discovered at Slapton Ley, but the bush on which it grew was cleared as part of conservation scrub clearance.
· Next, it was found on a hawthorn bush on the shores of the Drift Reservoir in Cornwall, but when the water level rose and submerged the bush, its only known modern site was once again lost.
· More recently it was found on a branch fallen from an apple tree in Herefordshire.
Not a very promising situation for its continued survival, but shortly after that, it was found in County Cork and as far as I know, that site is still extant. It also occurs on Guernsey on two bushes where I saw it recently. In Jersey however, it was last seen in an orchard back in 1966. A recent trip to the site confirmed that all the apple trees had gone.
On Boxing Day I met up with Mark Jackson and he showed me the two bushes each with just one Teloschistes chrysophthalmus. We had a good look round at other trees, but found no more. However, on our way back to the car, Mark found a minute, pink lichenicolous fungus growing on a twig. I photographed it, and sent off the photograph to the experts. It is Illosporiopsis christiansenii and new to Sussex. Mark is lucky in having an excellent eye for lichens, as well as a great enthusiasm for them.
Since the 23rd of December, I have learned that Teloschistes chrysophthalmus has turned up recently in four sites on the Isle of Wight as well as single sites in Dorset, Hampshire and Kent, so the discovery of it in Sussex links up all the counties in the South Eastern quarter of England. In the past, it was thought that Teloschistes chrysophthalmus was probably the most pollution sensitive lichen species, at least to the sulphur dioxide pollution that occurred in Britain. Its recently discovered distribution however would seem to refute this. In Sussex, the site is no more than 400 yards from the edge of the Brighton conurbation. Until relatively recently, there was a power station downwind at Shoreham, and with the whole of Brighton and Hove downwind of the site, the air cannot be considered pure, even with the considerable improvement in air quality throughout Southern England. Clearly Teloschistes chrysophthalmus is not behaving as the delicate, hyper pollution sensitive species it was previously thought to be.
Outside Britain, I have some experience of Teloschistes chrysophthalmus. It is certainly rare in Europe. I first saw it on a twig at Amelie les Bains in the French Pyrenees in 1974. In 1993, I found it in Corfu, and these experiences made me believe that because of the dry atmosphere any sulphur dioxide would not be turned to sulphurous acid, the active compound that causes havoc to pollution sensitive lichens.
In 1994, my ideas about the problems of air pollution and Teloschistes chrysophthalmus were somewhat shaken when I stayed in a hotel on the edge of Quito in Ecuador. On a Jacaranda tree in the grounds of the hotel, I found a lichen flora consisting of some of the most sensitive lichens known belonging to genera such as Lobaria and Sticta. Amongst the many other species, I found Teloschistes chrysophthalmus, and as will transpire, even more surprisingly I found Teloschistes flavicans. At the time, I did not know of the closely related Teloschistes exilis, which my record of Teloschistes chrysophthalmus might actually have been.
|Teloschistes exilis in Texas|
|Teloschistes flavicans in Guernsey|
|Xanthoria polycarpa in Hampshire|
|Teloschistes chrysophthalmus in Hampshire|
Naturalists should be encouraged to look out for Teloschistes chrysophthalmus. It appears so far to have been found mostly on mature hawthorn, and perhaps a lesser extent on blackthorn, which are blasted by strong, coastal winds from the south west. It is astonishing how similar Teloschistes chrysophthalmus can look to the common Xanthoria polycarpa when viewed from a short distance and I suspect it may have been overlooked for this. The Teloschistes has brighter orange discs, or fruits, and they are always surrounded by hair like cilia, or whiskers. These are never present surrounding the duller discs of Xanthoria polycarpa. Also intriguing was the presence of the lichenicolous fungus Illosporiopsis christiansenii on a different bush perhaps six feet away.