Lichens from the Roosevelt River Area in the Brazilian Amazon

: Lichens were investigated in Brazil in a small area along the Roosevelt River in Amazonas; 25 species are ﬁrst reports for Brazil, and 190 additional species are ﬁrst records for Amazonas state. As many as 24 species are described that are new to science: Allographa lineatipruinosa , Allographa variopruinata , Arthonia xanthopycnidiata , Astrothelium aurantioseptemseptatum , Astrothelium bulbosum , Astrothelium coloratum , Astrothelium inspersonovemseptatum , Astrothelium insulare , Astrothelium lau-reroides , Astrothelium marjoleinae , Astrothelium meandratum , Astrothelium multireﬂexum , Astrothelium myopicum , Astrothelium parabathelium , Astrothelium stellare (also known from Mato Grosso state), Astrothelium suprainspersum , Astrothelium xanthocavatum , Ocellularia fuscolichexanthonica , Ocellularia lichexanthocavata , Pertusaria amazonica


Introduction
The serious study of lichens in the Amazon started only recently, with the systematic exploration of all Amazonian states by the author and colleagues. In the last century and before, no papers were published citing more or less complete lists of species from a certain locality. The only paper citing more than 100 lichens from the Amazon [1] cited foliicolous species.
Somewhat surprisingly, apparently no lichenologist has ever carried out comprehensive collection in an Amazon area, or even one single tree, before we started this work (or at least the results were never published). This can be seen from the monographs from the last century. For instance, only 35 species of Trypetheliaceae [2] were known from the whole of Amazonian Brazil (an area of around 5 million km 2 ), based on all records available since the end of the 18th century. Here, I report as many as 83 species of this family in just one small locality of around 10 km 2 (less than a thousandth percent). Similarly, the monograph of Laurera Reichenb. (now partly included in Astrothelium Eschw. and partly in Bathelium Ach.) from 1957 [3] treats 23 species for the whole earth (150 million km 2 ), a number that is almost exactly equaled here on 10 km 2 .
One of the main research questions of our work is how diverse the lichens are in the Amazon. Even after 11 years of intense fieldwork, this is still difficult to assess. The Amazon is known to be a biodiversity hotspot for many groups of organisms, e.g., trees and butterflies, or probably even plants and insects. For other organism groups, such as bryophytes, it is reported to be much less diverse than, e.g., the Andes. In the past ten years, I visited and published lichen records and species from the Amazonian states of Rondônia [4][5][6][7][8][9], Amazonas [10], Amapá [11,12], Acre [13], Pará [14], Mato Grosso [15], and Tocantins [14]. Not every specimen could be identified or described yet, but the majority of the material has been published, although over 50 new Graphidaceae from the Amazon are still waiting to be published.
The Roosevelt river area is located in Amazonas state, at the southern border of the Amazone forest region. The visited area consists largely of mature undisturbed tropical One of the problems with collecting lichens in rainforests is that the canopies of the trees are generally out of reach, and the thicker branches in the lower canopy can be especially full of species. The twigs usually yield the same small set of pioneer species that is widely wind-dispersed, while the zone of the branches is generally still, and species cannot disperse well, leading to local endemism. I of course examined every fallen twig, branch, and tree I saw, but I was lucky to find one recently fallen Enterolobium tree (common names: conacaste, guanacaste, caro caro, devil's ear tree, monkey-ear tree, or elephant-ear tree; Fabaceae family), which I sampled exhaustively. I collected 136 lichen specimens from it, in which I found 98 different species ( Table 2), 84 of which could be identified and 7 of which are described below (only one of which was also found elsewhere). Among the unidentified species, there are three additional undescribed Astrothelium species which are, however, overmature.   An indication of the incompleteness of any field trip is that in the present Roosevelt location, as many as 48 species were only found on one recently fallen Enterolobium tree (including seven new species to science). If I had not found this tree, the list would be considerably shorter; if I had been able to examine more complete trees, who knows how many more species I would have found?
Some additional observations can be made based on the c. 15,000 collections collected in the past ten years in Amazonian Brazil: The borders of the Amazon region in the North (Amapá), West (Acre), and East (Tocantins and Pará) are relatively low in species. The central region (Manaus) is richer, but the richest areas are in the South borders (Rondônia, Mato Grosso, and the Roosevelt locality in Amazonas reported upon here). We have no offhand explanation for this; there is no correlation with the supposedly relict areas where rainforest remained in drier geological times, as compared to other Amazon areas that became savannahs. Cristalino in Mato Grosso and the Roosevelt locality in Amazonas share the abundance of exposed rock which contributes to the diversity, but not by as many species.
One analysis I made was if I ever approached the saturation point while collecting, i.e., whether I knew how many species occur in a visited area. I found that for the two places where I spent several field days (Parque Natural, Porto Velho, Rondônia and Reserva Florestal Adolphe Ducke, Manaus, and Amazonas), the number of new species found every day after the third day was not yet falling.
Chemistry: Thallus UV-, C-, K+ yellow, KC-, P+ orange. TLC: Stictic acid. Etymology: Named after the variable pruina. Ecology and distribution: On tree bark in primary rainforest; only known from Brazil. Discussion: This species would key out in the world key to Graphis [17] in Group 10 at couplet 3: Labia often with white pruina.
Chemistry: Thallus UV-, C-, K+ yellow, KC-, P+ orange. TLC: Stictic acid. Etymology: Named after the variable pruina. Ecology and distribution: On tree bark in primary rainforest; only known from Brazil. Discussion: This species would key out in the world key to Graphis [17] in Group 10 at couplet 3: Labia often with white pruina.
Chemistry: Thallus UV-, C-, K-, KC-, P-; pycnidia UV+ yellow. TLC: Lichexanthone. Etymology: Named after the yellow UV reaction of only the pycnidia. Ecology and distribution: On wood in primary rainforest; only known from Brazil. Discussion: This species is most similar to common pantropical Arthonia antillarum Fée, but differs by the lichexanthone being only present on the pycnidia instead of the thallus.
Chemistry: Thallus UV+ orange, C-, P-, K+ red. TLC: An anthraquinone. Etymology: Named for the orange thallus and the 7-septate ascospores. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key J, couplet 40: Thallus with superficial orange pigment.
Etymology: Named for the bulbose pseudostromata. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 16: Pseudostromata with pigment that is not very pronounced but causes a UV+ orange reaction.
Etymology: Named for the bulbose pseudostromata. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 16: Pseudostromata with pigment that is not very pronounced but causes a UV+ orange reaction.
An anthraquinone. Etymology: Named for the bulbose pseudostromata. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 16: Pseudostromata with pigment that is not very pronounced but causes a UV+ orange reaction.
Etymology: Named for the various, both in daylight and under UV. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 4: Lichexanthone present on thallus and pseudostromata.
(both anthraquinone and lichexanthone present on the pseudostromata), C-, P-, K+ red. TLC: An anthraquinone and lichexanthone. Etymology: Named for the various, both in daylight and under UV. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 4: Lichexanthone present on thallus and pseudostromata.
Chemistry: Thallus UV-, C-, P-, K-. TLC: nil. Etymology: Named for the island-shaped pattern formed by the pseudostromata. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key K, couplet 23: Ascospores 13-16-septate, ostioles single, pseudostromata whitish, almost flush with the thallus.
Chemistry: Thallus UV-, C-, P-, K-. TLC: nil. Etymology: Named for the island-shaped pattern formed by the pseudostromata. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key K, couplet 23: Ascospores 13-16-septate, ostioles single, pseudostromata whitish, almost flush with the thallus.
Etymology: Named for the similarity to the former genus Laurera. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 20: Pseudostromata raised, brownish, but UV+ orange.
Etymology: Named for the similarity to the former genus Laurera. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 20: Pseudostromata raised, brownish, but UV+ orange.
Etymology: Named for the my wife, whom I married in the week that I described this species. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key J, couplet 40: Thallus and pseudostromata orange-green, ascospores 7-9-septate, 62-67 × 11-13 µm.
Etymology: Named for the various UV-reactions of the different thallus parts. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 4: Lichexanthone only on the ostioles; pseudostromata yellow.
Etymology: Named for the various UV-reactions of the different thallus parts. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 4: Lichexanthone only on the ostioles; pseudostromata yellow.
Etymology: Named for the various UV-reactions of the different thallus parts. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 4: Lichexanthone only on the ostioles; pseudostromata yellow.
Etymology: Named for the ostioles that give the impression of myopic eyes. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key J, couplet 40: Thallus and pseudostromata orange-green, ascospores 7-9-septate, 35-45 × 9-10 µm.
Etymology: Named for the ostioles that give the impression of myopic eyes. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key J, couplet 40: Thallus and pseudostromata orange-green, ascospores 7-9-septate, 35-45 × 9-10 µm.
Etymology: Named for the similarity to Bathelium. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 13: Pseudostromata brown, superficial; thallus and ostioles UV+ yellow.
Etymology: Named for the brilliantly UV+ yellow ostioles that evoke a starry night. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 13: Pseudostromata brown, superficial; only ostioles UV+ yellow.
Etymology: Named for the brilliantly UV+ yellow ostioles that evoke a starry night. Ecology and distribution: On tree bark in rainforest; only known from Brazil.
Etymology: Named for the inspersion in the upper half of the hamathecium. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key H, couplet 7: Hamathecium inspersed with hyaline oil droplets, but only in the upper half, ascospores 18-21 × 6-7.5 µm.
TLC: Lichexanthone. Etymology: Named for the inspersion in the upper half of the hamathecium. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key H, couplet 7: Hamathecium inspersed with hyaline oil droplets, but only in the upper half, ascospores 18-21 × 6-7.5 µm.
Etymology: Named for the yellow UV reaction and the cavate ascomata. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, couplet 13: Pseudostromata almost flush with the thallus, whitish, with UV+ yellow patches, ascospores 140-175 × 21-24 µm.
TLC: Lichexanthone. Etymology: Named for the yellow UV reaction and the cavate ascomata. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species would key out as follows in the world key [18]: key L, co 13: Pseudostromata almost flush with the thallus, whitish, with UV+ yellow patche cospores 140-175 × 21-24 µm.
Etymology: Named after the brown ascospores and the thallus with lichexanthone. Ecology and distribution: On tree bark in primary rainforest; only known from Brazil. Discussion: This species differs from all known species in the genus (and in the family) due to the combination of 3-septate brown ascospores, lichexanthone in the thallus, and the presence of a columella that is brown inside.
C-, K-, KC-, P-. TLC: Lichexanthone and hypothamnolic acid. Etymology: Named after the brown ascospores and the thallus with lichexanthone. Ecology and distribution: On tree bark in primary rainforest; only known from Brazil. Discussion: This species differs from all known species in the genus (and in the family) due to the combination of 3-septate brown ascospores, lichexanthone in the thallus, and the presence of a columella that is brown inside.
Ecology and distribution: On tree bark in primary rainforest; only known from Brazil. Discussion: This species is very similar to the type of the genus O. cavata, but it has lichexanthone in the thallus.
Etymology: Named after the small muriform ascospores. Ecology and distribution: On tree bark in primary rainforest; only known from Brazil.
Discussion: This species would key out in the world key [19] in Group 21 at couplet 4: Thallus with isidia, with divaricatic acid. Pertusaria species are very scarce in the Amazon, just like Lecanora and in general all lichens with trebouxioid algae. This species is locally very abundant, covering many complete rockfaces. The new species is markedly different from any described species due to the presence of isidia and the chemistry of lichexanthone and divaricatic acid. Over 100 species of Pertusaria are already described or reported from Phaeographis xantholirellinata Aptroot, sp. nov. Figure 21.
Etymology: Named after the small muriform ascospores. Ecology and distribution: On tree bark in primary rainforest; only known from Brazil. Discussion: This species would key out in the world key [19] in Group 21 at couplet 4: Thallus with isidia, with divaricatic acid. Pertusaria species are very scarce in the Amazon, just like Lecanora and in general all lichens with trebouxioid algae. This species is locally very abundant, covering many complete rockfaces. The new species is markedly different from any described species due to the presence of isidia and the chemistry of lichexanthone and divaricatic acid. Over 100 species of Pertusaria are already described or reported from Brazil, but a preliminary analysis of our recently collected specimens suggests that at least 200 species probably occur there.
Etymology: Named after the lirellae that are UV+ yellow. Ecology and distribution: On tree bark in primary rainforest; only known from Brazil. Discussion: This species differs from all known species in the genus (and family) by the yellow reflecting crenate lirellae.
Etymology: Named after the lirellae that are UV+ yellow. Ecology and distribution: On tree bark in primary rainforest; only known from Brazil. Discussion: This species differs from all known species in the genus (and family) by the yellow reflecting crenate lirellae.
Chemistry: Thallus UV-, C-, K-, KC-, P-. TLC: nil. Etymology: Named for the branched isidia. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Description: Thallus glossy, olivaceous green, up to 7 cm diam., surrounded by a whitish prothallus line. Isidia in irregular groups, cylindrical, irregularly branched, c. 0.1 mm wide and up to 0.8 mm long, often ending in white prothallus filaments. Ascomata and pycnidia not observed.
Chemistry: Thallus UV-, C-, K-, KC-, P-. TLC: nil. Etymology: Named for the branched isidia. Ecology and distribution: On tree bark in rainforest; only known from Brazil. Discussion: This species was sterile, but sequence data showed that it is (indeed) a Porina. It differs from all other isidiate species so far described in the irregularly branched isidia that often end in white prothallus.
Pseudopyrenula connexa Aptroot, sp. nov. Figure 23. Description: Thallus microsquamulose on a continuous black hypothallus, consist of a 0.1-0.4 mm thick layer of squamules, greyish green mottled with bright brick patches, surrounded by a black prothallus line, which is a continuation of the hypothall Squamules greatly dissected into lobules of c. 0.03 mm wide, flattened, at the margin of fragmenting into small propagules. Photobiont trebouxioid. Ascomata and pycnidia observed.
Chemistry: Thallus UV-, C-, K+ purple, KC-, P-. TLC: Norsoloronic acid. Etymology: Named after the squamules. Ecology and distribution: On tree bark in primary rainforest; only known from Braz Discussion: This species would key out in the world key [20] at couplet 2: Thal microsquamulose.  Description: Thallus microsquamulose on a continuous black hypothallus, consisting of a 0.1-0.4 mm thick layer of squamules, greyish green mottled with bright brick red patches, surrounded by a black prothallus line, which is a continuation of the hypothallus. Squamules greatly dissected into lobules of c. 0.03 mm wide, flattened, at the margin often fragmenting into small propagules. Photobiont trebouxioid. Ascomata and pycnidia not observed.
Chemistry: Thallus UV-, C-, K+ purple, KC-, P-. TLC: Norsoloronic acid. Etymology: Named after the squamules. Ecology and distribution: On tree bark in primary rainforest; only known from Brazil. Discussion: This species would key out in the world key [20] at couplet 2: Thallus microsquamulose.
Funding: This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-Brasil (CAPES)-Finance Code 001 who provided a visiting professorship to the author. The Stichting Hugo de Vries Fonds kindly gave a generous grant for the fieldwork.
Institutional Review Board Statement: Not applicable.

Informed Consent Statement: Not applicable.
Data Availability Statement: Not applicable.

Conflicts of Interest:
The author declares no conflict of interest.