Going extinct before being discovered? New lichen fungi from a small fragment of the vanishing Atlantic Rainforest in Brazil

Abstract

In the frame of an ongoing lichen inventory of Atlantic Rainforest remnants in Northeast Brazil, five new species of Graphidaceae were discovered in a small forest fragment, Mata do Cipó, in Sergipe state, the smallest state of Brazil and among those with the highest deforestation rate in the country. An additional new species had already been collected in Panama before and was now also found in the Mata do Cipó and is described here as well. In total, 40 species of Graphidaceae are reported for this remnant, including a large number of taxa indicative of well-preserved rainforest. The new species are: Fissurina atlantica T.A. Pereira, M. Cáceres & Lücking, sp. nov., Graphis subaltamirensis Passos, M. Cáceres & Lücking, sp. nov., Ocellularia cipoensis L.A. Santos, M. Cáceres & Lücking, sp. nov., O. sosma T.A. Pereira, M. Cáceres & Lücking, sp. nov., O. submordenii Lücking, sp. nov. (also known from Panama), and Pseudochapsa aptrootiana M. Cáceres, T.A. Pereira & Lücking, sp. nov. The findings are discussed in the context of the strong fragmentation of the Atlantic Rainforest, with individual remnants apparently serving as refugia for residual populations of rare species of lichen fungi that were more widely distributed in the past, but currently seem to occur only in isolated fragments.

Diversity of foliicolous lichens in isolated montane rainforests (Brejos) of northeastern Brazil and their biogeography in a neotropical context

“…In addition to paleoclimate, it must also be noted that the southeastern Amazon and the northeastern Atlantic rainforest are highly fragmented, although the isolation of the Brejos is due to natural causes. Fragmentation of the northeastern Atlantic rainforest is the result of intensive human activities that left less than 5% of its original cover (Metzger et al, 2009;Pereira, Passos, Santos, Lücking, & Cáceres, 2018;Ribeiro, Metzger, Martensen, Ponzoni, & Hirota, 2009;Tabarelli, Aguiar, Ribeiro, Metzger, & Peres, 2010). Whereas human impact cannot explain evolutionary traits, one would expect that such degradation and fragmentation further reduces species richness, while at the same time increasing spatial heterogeneity in species composition due to stochastic effects, so the reduced species richness at all of the eastern sites may in part be the result of these recent human activities.…”

Phylogenetic structure of lichen metacommunities in Amazonian and Northeast Brazil

“…Given that lichens are excellent indicators of ecological continuity and the conservation status of forest fragments (Ranft et al, 2018; Rivas Plata et al, 2008), analysis of their phylogenetic community structure may be a powerful tool to assess forest conservation status, such as suggested by studies on woody plants (Matos et al, 2017; Ribeiro et al, 2016; Santos et al, 2010, 2014; Silva‐Junior et al, 2018). Particularly the northern portion of the Atlantic forest suffer from high levels of fragmentation, and many of these fragments have been shown to harbor previously unrecognized lichen fungal species (Pereira et al, 2018).…”

“…Given that lichens are excellent indicators of ecological continuity and the conservation status of forest fragments (Ranft et al, 2018;Rivas Plata et al, 2008), analysis of their phylogenetic community structure may be a powerful tool to assess forest conservation status, such as suggested by studies on woody plants (Matos et al, 2017;Ribeiro et al, 2016;Santos et al, 2010Santos et al, , 2014Silva-Junior et al, 2018). Particularly the northern portion of the Atlantic forest suffer from high levels of fragmentation, and many of these fragments have been shown to harbor previously unrecognized lichen fungal species (Pereira et al, 2018). ACKNOWLEDGMENTS E. L. L. N. acknowledges CAPES-Coordenação de Aperfeiçoamento de Pessoal de Nível Superior for providing a doctoral scholarship and CNPq-Conselho Nacional de Desenvolvimento Científico e Tecnológico for an additional scholarship to perform a sandwich stay at BGBM in Germany (SWE, process 233421/2014-9); CNPq is also thanked for financial support (CNPq-Protax process 562.330/2010-0, INCT-Herbário Virtual process 465.420/2014-1, Sisbiota process 563.342/2010-2).…”

“…Furthermore, human‐induced disturbance may affect phylogenetic diversity and structure of plant communities, leading to phylogenetic clustering of lineages that included disturbance‐tolerant or pioneer species (Matos et al, 2017; Ribeiro et al, 2016; Santos et al, 2014; Santos et al, 2010; Silva‐Junior et al, 2018). This offers a diverse panorama for extending disturbance‐focused approaches to lichen communities in these regions (Pereira et al, 2018).…”

Reproduction and Dispersal of Biological Soil Crust Organisms

“…Some lichens reproduce asexually using unspecialized thallus fragments (Armstrong, 2017;Almeida Pereira et al, 2018) or through the formation of small-specialized asexual structures containing cells of both the mycobiont and the photobiont. These specialized asexual structures include soredia, isidia, and lobules (Ott et al, 1993).…”