- Scientific name
- Ramalina portosantana
- Common names
- IUCN Specialist Group
- Assessment status
- Assessment date
- IUCN Red List Category
- IUCN Red List Criteria
- Aptroot, A. & Thor, G.
- Scheidegger, C.
This macrolichen occurs only on one volcano on a small island. It was described in 1990 by H. Krog and has never been found anywhere else, but is always found by lichenologists visiting its only site. With a severely restricted range and continuing decline in habitat quality at its single location, it is assessed as Critically Endangered B1ab(i,ii,iii)+2ab(i,ii,iii).
Confined to exposed lava rock on and near the summit of the Pico do Facho on Porto Santo, the area of occupancy of this species is 2 km², although the area that it actually occupies is estimated to be significantly less than this.
Population and Trends
The total population is estimated as 500-1000 individuals (Sparrius et al. 2017).
Population Trend: decreasing
Habitat and Ecology
On exposed lava rock on and near the summit of the Pico do Facho volcano on Porto Santo.
This species is threatened by a number of direct and indirect threats. The direct threats facing this species include increased climbing of the summit by tourists which will deteriorate the populations. A further direct threat is collecting by lichenologists or naturalists, which should be forbidden. A future increase in wildfires could also threaten this species (Sparrius et al.
The indirect threats facing this species include climate change which may change this unique habitat, and even with subtle changes the chances are high that the species goes extinct soon. It will in any case not be able to successfully colonise another locality, not on its own, and possible also not with human help, as the conditions are apparently critical.
Tourism to the summit of the Pico de Facho should be strictly regulated, either by forbidding access altogether (which will impossible to control) or rather by opening a small trail and putting an information shield in place alerting tourists to the unique lichens present, and the harm done to them by trampling.
The species should feature on a leaflet with protected plants.
Source and Citation
Aptroot, A. & Thor, G. 2020. Ramalina portosantana. The IUCN Red List of Threatened Species 2020: e.T70380974A175190113. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T70380974A175190113.en
.Accessed on 3 February 2024