Thallus saxicolous, ascending or more or less decumbent, fragile, up to 3 cm long, several thalli growing close together from separate holdfasts. Laciniae solid, 0-3-0-8 mm wide, subterete, uneven, tapering to attenuate apices, here and there with fragmentation areas; shortly linear to ellipsoid pseudocyphellae present on all branches. Soredia absent. Cortex c. 25 um thick, chondroid tissue rilling most of the branch, medullary tissue and algal cells mainly centrally located, penetrating to the surface in pseudocyphellae. Apothecia common,
lateral on more or less geniculate branches, disc up to 2 mm diam.; spores bilocular, 12-13 x 5-6 um. Chemistry: Divaricatic acid, salazinic acid, triterpenoids, usnic acid.
The species resembles the also Porto Santo endemic R. timdaliana, however the later never presents salazinic acid and the chondroid axis is discontinous.
(Source: Krog H. 1990 New ramalina species from Porto Santo, Madeira. - Lichenologist 22(3): 241-247)
There only exists a a few small populations on two volcanoes in the world. It is threatened by accidental extinction by trampling, grazing and possibly collecting.
Criterion A: There is not current information about the trends of population size over long time periods, so it is not possible to apply this criterium.
Criterion B: Both B1 and B2 subcriteria could be applied as the extent of occurrence is smaller than 100 km2 and the area of occupancy is likely smaller than 10 km2. However, the species does not fit the two necessary conditions for this criterium. It only satisfy subcriterion B1a (or B2a) as it occurs in a single population worldwide. However no available information support the application of subcriteria a or b.
Criterion C. No information is available about the total number of individuals of this species. Thus, subcriteria C1 or C2 are not applicable.
Criterion D. The total number of individuals is unknown, considering 1m2= 1 ind, it is likely the number of individuals is less than 250. D1= Endangered. The Area Of Occupancy is smaller than 20 km2 and the number of locations is 1 which fits subcriterion D2 (Vulnerable).
Criterion E. No quantitave analyses have been carried out.
The species has been assessed as Vu (D2) until more research on the actual number of individuals and population size is carried out.
Assessment: Endangered under criterion D1.
Endemic of the Portuguese Island of Porto Santo. Only present at Pico do Facho and on one of other old volcano, Terra Chã.
Growing together with other endemic macrolichens, such as Anzia centrifuga, Ramalina confertula, R. erosa, R. nematodes and R. timdaliana.
Only two populations are known, on two volcanoes. The total number of specimens seen in May 2015 on these licalities was less than 25 (Aptroot, pers. comm.). However, only 10 % of the suitable habitat on Port Santo could be investigated (much of it is on steep cliffs), and the existence of further populations is likely.
On volcanic acidic rocks. Also once seen on dry tree bark of Pinus.
Ramalina jamesii occurs only on one volcano. It could be threatened by accidental extinction from tourism, fire, trampling, grazing and possibly collecting if development of tourism occurred in the vicinity of the population. The past impact of these threats has not been documented. There is a road in to the locality and if this is not changed then the impact of these threats is likely to remain negligible. However, expansion of this road for development for tourism would result in the habitat becoming heavily disturbed and degraded. This is therefore a plausible threat to the species.
No conservation plan is available. There is an urgent need for a detailed assessment of population size, the extent of occurrence and trend.
The mountain tops should be protected and the visitors should be required to keep to a track.
Tourism to the summit of the Pico de Facho should be strictly regulated, either by forbading accees altogether (which will impossible to control) or rather by opening a small trail and putting an information shield in place alerting the tourist on the unique lichens present, and the harm done to them by trampling.
The known locality at Terra-Chã is along a trail and is susceptible to accidental removing. However, the existence of further localities, in places that are difficult to reach, is likely.
The species should feature on a leaflet with protected plants.
Phylogenetic studies are being carried out. In May 2015, an attempt has been made to assess the actual population size. Only about 25 specimens were found, but only about 10 % of the suitable habitat could be investigated.
Krog H. 1990 New ramalina species from Porto Santo, Madeira. - Lichenologist 22(3): 241-247
A. Aptroot & F. Schumm. 2008. Key to Ramalina species known from Atlantic islands, with two new species from the Azores. Sauteria 15: 21-57.