Ten new species of Trypetheliaceae are described: Astrothelium bullatothallinum from Venezuela, which is close to A. aeneum but differs by the bullate thallus with a thick cortex, intermixed in a mosaic with the prothallus; A. cayennense from French Guiana, which is similar to A. flavomegaspermum but with a yellow pigment in the pseudostroma near the ostioles; A. diaphanocorticatum from Papua New Guinea, which has a bullate thallus with a thick hyaline cortex and 3-septate ascospores of 25–28×10–12 μm; A. macroeustomum from French Guiana, with joint lateral ostioles, UV+ yellow ostiolar region and 5-septate ascospores of 50–55×12–17 μm; A. minicecidiogenum from Costa Rica, with muriform ascospores of 70–90×20–25 μm, without pseudostromata, with solitary ascomata, lateral ostioles and an inspersed hamathecium; A. palaeoexostemmatis from Thailand, which is similar to A. exostemmatis but with larger, I+ blue ascospores; A. quasimamillanum from Brazil, with muriform ascospores of 30–33×9·5–10·5 μm, without pseudostromata, with solitary ascomata, lateral ostioles and an inspersed hamathecium; A. studerae from Brazil, with astrothelioid ascomata, lichexanthone only in the pseudostromata, 3-septate ascospores of 21·5–23·0×6·5–7·5 μm; A. tanianum from Malaysia, with a bullate thallus, solitary ascomata, covered by the thallus, (9–)11(–15)-septate ascospores, 75–100×20–22 μm; and Pseudopyrenula miniflavida from Brazil, with a yellow-inspersed hamathecium, the inspersion dissolving in KOH without colour change, and 3-septate ascospores, 15–17×5·5–6·5 μm. The unusually thick, hyaline cortical layer of the thallus of Astrothelium diaphanocorticatum, through which the individual algal cells are clearly visible, is discussed. Furthermore, 30 species are reported from 34 countries in which they had previously been unrecorded; one (Astrothelium inspersaeneum) is from a new continent, Asia.

The following 46 new species of Trypetheliaceae are described: Astrothelium aenascens Aptroot from Papua New Guinea, which is similar to A. aenoides but differs by the hamathecium which is not inspersed; A. alboverrucoides Aptroot from Indonesia with globose ascomata with constricted base, internally similar to A. megaspermum; A. clypeatum Aptroot & Gueidan from Vietnam with black conical ascomata in which the pseudostroma is reminiscent of a clypeus, a rimose thallus, and 3-septate ascospores, 85–95×22–25 µm; A. colombiense Aptroot from Colombia with 1 muriform ascospore of 240–300×45–50 µm per ascus, and an inspersed hamathecium; A. condoricum Aptroot from Ecuador with a bright orange thallus and contrasting bright scarlet internal pigment, and muriform ascospores, 38–42×18–21 µm; A. corallinum Aptroot from Guyana, which is most similar to A. ochroleucoides but the thallus is without lichexanthone; A. dicoloratum Aptroot from Venezuela with an orange thallus and more yellowish pseudostromata with usually only 1 ascoma, and 9–11-septate ascospores; A. ecuadoriense Aptroot from Ecuador with ascospores 2 per ascus, muriform, 80–175×25–50 µm, and an inspersed hamathecium; A. flavomaculatum Aptroot from Ecuador, Guyana and Venezuela which is similar to A. graphicum, but with ascospores 50–75×12–25 µm; A. flavomeristosporum Aptroot from the Philippines and Ecuador with mostly simple ascomata with an orange to yellow, inspersed hamathecium and muriform ascospores 140–200×25–30 µm; A. flavostiolatum Aptroot from Ecuador with bright yellow ostioles and a very irregular thallus, and muriform ascospores, 175–230×35–45 µm; A. guianense Aptroot from Guyana with a very irregular thallus, eccentric, fused ostioles and ascospores 4 per ascus, muriform, 70–80×20–25 µm; A. inspersogalbineum Aptroot & Weerakoon from Singapore which is similar to A. macrocarpum but with the hamathecium inspersed; A. komposchii Aptroot from Venezuela with chimney-like ostioles and a very irregular, almost squamulose thallus and muriform ascospores, 130–180×35–45 µm; A. laurerosphaerioides Aptroot from Guyana with aggregated ascomata with internally and partly (when abraded) also superficially orange anthraquinone pigment, ascospores 2 per ascus, muriform, 110–130×30–35 µm; A. lucidomedullatum Aptroot from Ecuador with lichexanthone in the medulla of the thallus, ascospores 4 per ascus, muriform, 80–115×25–35 µm; A. lucidostromum Aptroot from Guyana which is similar to A. eustomuralis but lichexanthone is present in the whole pseudostroma; A. lucidothallinum Aptroot from Guyana with the thallus containing lichexanthone, ascomata in pseudostromata without lichexanthone, ostioles apical, hamathecium not inspersed, ascospores muriform, 70–90×18–20 µm; A. mediocrassum Aptroot from Guyana which resembles A. octosporum but without lichexanthone in the thallus or pseudostromata, muriform ascospores, 70–80×22–25 µm, with median septum strongly thickened; A. megatropicum Aptroot from Guyana with 3-septate ascospores 100–120×33–35 µm, and hemispherical dark brown pseudostromata; A. megochroleucum Aptroot from El Salvador with 3-septate ascospores 60–70×16–18 µm and lichexanthone in the thallus and pseudostromata; A. neoinspersum Aptroot from El Salvador which is similar to A. aenascens but with bright yellow pseudostromata; A. perspersum Aptroot & Ertz from Gabon which is similar to A. scoria but with ascospores 26–38×7–9 µm; A. philippinense Aptroot & Schumm from the Philippines without pseudostromata, ostiole apical, hamathecium inspersed, ascospores muriform, 125–170×30–35 µm, 4 per ascus; A. pseudannulare Aptroot & Etayo from Ecuador with the appearance of the A. puiggarii-group, but differing from all other species of it by the 3-septate ascospores 80–88×32–36 µm, which are 2–4 per ascus; A. pseudodissimulum Aptroot from Papua New Guinea with K+ red crystals in the ascoma wall and 5-septate ascospores of 25–33×9–11 µm; A. pseudoferrugineum Aptroot from Indonesia, of the A. conicum-group with an orange thallus and pseudostroma pruina, differing from A. ferrugineum by the ascospores 28–31×9–11 µm and the more glossy thallus; A. pseudomegalophthalmum Aptroot from Colombia, similar to A. megaspermum but differing by the 7-septate ascospores 152–166×32–37 µm; A. rimosum Aptroot from Guyana and Colombia with 7–11-septate ascospores 110–150×30–37 µm and a rimose thallus with yellow medulla; A. sanguineoxanthum Aptroot from Brazil with the thallus containing lichexanthone and pseudostromata with numerous immersed round ascomata, the whole inside of which is full of red, K+ green pigment; A. septemseptatum Aptroot from Guyana and Venezuela with the thallus and pseudostromata UV+ yellow and 7–9-septate ascospores 50–55×12–17 µm; A. sexloculatum Aptroot from Guyana and Papua New Guinea with 5-septate ascospores 25–27×7–11 µm and lichexanthone in the thallus and pseudostromata; A. sipmanii Aptroot from Guyana with simple ascomata with 5-septate ascospores 100–150×35–40 µm and an inspersed hamathecium; A. trypethelioides Aptroot from Venezuela with fused ostioles, an inspersed hamathecium and 7–9-septate ascospores 49–52×13–16 µm; A. ultralucens Aptroot from Venezuela with lichexanthone in the thallus and pseudostromata, fused ostioles and 3-septate ascospores over 105–130×35–42 µm; A. vulcanum from Guyana, of the A. nitidiusculum-group with simple ascomata, an inspersed hamathecium and lichexanthone; A. zebrinum Aptroot from Guyana with fused ostioles and 7-septate ascospores 60–70 µm long, without lichexanthone, anthraquinones and inspersion; Polymeridium rhodopruinosum Aptroot from Puerto Rico with red pruina on the ascomata and 3-septate ascospores 17–19×3·5–5·0 µm; Pseudopyrenula americana Aptroot from Guyana with 3-septate ascospores 26–32×7–10 µm, without inspersion and without lichexanthone; P. guianensis Aptroot from French Guiana and Surinam with a hyaline hamathecium with inspersion, a thallus with lichexanthone and 3-septate ascospores 21–25×6–9 µm; P. hexamera Aptroot from Venezuela with 5-septate ascospores 16–21×6–7 µm, lumina clearly diamond-shaped; P. thallina Lücking & Aptroot from Costa Rica with a greenish corticate thallus and 3-septate ascospores, 21–25×6–9 µm; Trypethelium infraeluteriae Aptroot & Gueidan from Vietnam which is similar to T. subeluteriae but with lower pseudostromata and ascospores 7–9-septate, 37–42×9–11 µm; Viridothelium inspersum Aptroot from Papua New Guinea with solitary, immersed ascomata, an inspersed hamathecium, and 12–14-septate ascospores, 60–75×12–17 µm; V. kinabaluense Aptroot from Sabah which is similar to V. indutum with emergent black ascomata, but with 17–25-septate ascospores 100–150×18–23 µm; and V. solomonense Aptroot from the Solomon Islands having ascomata with lateral, partly fused ostioles and black clypeus, and ascospores 15–19-septate, 75–98×17–20 µm. The new species are known from Brazil, Colombia, Costa Rica, Ecuador, El Salvador, Gabon, Guyana, Indonesia, Papua New Guinea, the Philippines, Puerto Rico, Sabah, Singapore, Solomon Islands, Surinam, Venezuela and/or Vietnam.

The following 24 new species of Trypetheliaceae are described after three weeks of fieldwork in an area with a radius of 50 km around Porto Velho in Rondônia: Astrothelium bivelum with astrothelioid ascomata, 5-septate ascospores with polar gelatinous caps, and a thallus without lichexanthone; A. curvisporum with bent, 5-septate ascospores of 115–135×29–36 μm with a 17–22 μm thick gelatinous layer; A. decemseptatum with pseudostroma that are essentially black and look like breaking through the bark, with anthraquinones mostly on the pseudostromata but also on some parts of the thallus, best seen under UV light as the colour of the pruina is not very strong, and ascospores (7–)9–11-septate, fusiform, 50–65×11–17 μm; A. disjunctum with black pseudostroma and ascospores 3-septate, (27–)29–33×(8–)12–14 μm; A. duplicatum which is similar to A. mesoduplex, but pseudostroma are only yellowish inside and ascospores 45–55×11–15 μm; A. eumultiseptatum which is similar to A. eustomum, but with 9–11-septate ascospores of 65–70×15–17 μm; A. eustomurale which is also similar to A. eustomum, but with submuriform ascospores of 37–45×15–19 μm; A. flavoduplex which is similar to A. mesoduplex, but with ascospores 110–350×20–27 μm and the thallus containing lichexanthone; A. flavomurisporum with deeply immersed ascomata with muriform ascospores of 165–200×28–35 μm, with a distinctly thickened central septum and yellow oil; A. flavostromatum which is close to A. aeneoides and mainly differs by the bullate thallus and the cream pseudostromata; A. flavum which is similar to A. aeneum, but differs in the contrast between the linear to reticulate yellow stromata and the unpigmented thallus, and the ascospores of 16–18×6–7 μm; A. mesoduplex which is similar to A. flavoduplex, but with ascospores 90–100×20–23 μm and a thallus without lichexanthone; A. nigrum with mostly conical black pseudostromata that contrast sharply with the thallus, superficially resembling Pyrenula infraleucotrypa; A. novemseptatum which is similar to A. eumultiseptatum, but without lichexanthone anywhere in the thallus or pseudostroma; A. ochroleucoides which is similar to A. corallinum, but with lichexanthone on the thallus and pseudostromata; A. octoseptatum which is similar to A. eumultiseptatum, but with the whole pseudostroma, not just the ostioles, containing lichexanthone, and ascospores somewhat asymmetrical, which is highlighted by the unusual dominant even number of septa (eight) and the asymmetrically placed central septum in the case of uneven septum numbers; A. quatuorseptatum which is similar to A. octoseptatum Aptroot & M. Cáceres, but without lichexanthone, ascospores somewhat asymmetrical, which is highlighted by the unusual dominant even number of septa (four) and the asymmetrically placed central septum in the case of uneven septum numbers; A. robustosporum with solitary ascomata with an eccentric ostiole, and ascospores 11–15-septate, 90–125×20–27 μm; A. solitarium which is similar to A. ceratinum (Fée) Aptroot & Lücking, but with ascospores 33–36×10–11 μm; A. stromatofluorescens which is close to A. phlyctaena, but with lichexanthone only on the pseudostroma, not on the thallus; A. supraclandestinum is close to A. subclandestinum, but the hamathecium is not inspersed; A. testudineum with solitary ascomata with an eccentric ostiole, an inspersed hamathecium, and ascospores 8 per ascus, muriform, 50–65×23–27 μm; A. xanthosuperbum which is similar to A. disjunctum, but with muriform ascospores, 130–160×28–35 μm; and Pseudopyrenula flavoreagens which is similar to P. subgregaria, but with lichexanthone in the thallus. Only a few species were also found elsewhere, such as other areas of Brazil, or in Venezuela, Colombia, Guyana, Panama, Australia and/or Papua New Guinea. Currently, 55 species of Trypetheliaceae are known from this spot, including 46 species of Astrothelium. The Amazon basin is the centre of diversity for the family, at least for Astrothelium, the largest genus in the family.

The present treatment shows that the lichen family Trypetheliaceae is an important component of lowland and montane tropical forests in Bolivia. A total of 75 species are currently recognized in Bolivia, of which 24 are new to science and a further 37 are reported for the first time from the country. The following species are described: Architrypethelium penuriixanthum Flakus & Aptroot sp. nov. that differs from A. hyalinum in the lack of lichexanthone in the thallus; Astrothelium amylosporum Flakus & Aptroot sp. nov. that differs from A. subdisjunctum in having 8-spored asci and amyloid ascospores; A. bullatum Flakus & Aptroot sp. nov. that differs from A. megaspermum in having a bullate thallus, a clear hamathecium, 8-spored asci and smaller amyloid ascospores; A. carrascoense Flakus, Kukwa & Aptroot sp. nov. that differs from A. meristosporum in having broader ascospores without distinctly thickened median septa, an unidentified xanthone as major substance, and mostly eccentric ostioles; A. elixii Flakus & Aptroot sp. nov. that differs from all other Astrothelium species in the presence of lichexanthone in the outer layer of thallus and pseudostromata and isohypocrellin inside the pseudostromata, and muriform ascospores; A. inspersotuberculosum Flakus & Aptroot sp. nov. that differs from A. tuberculosum in having an inspersed hamathecium; A. megaeneum Flakus & Aptroot sp. nov. that differs from A. croceum in having a thallus covered by parietin, and mostly fused ascomata with intermediate, fused to separated ostioles surrounded by a common ostiolar area; A. neodiplocarpum Flakus, Kukwa & Aptroot sp. nov. that differs from A. diplocarpum in the absence of medullary pigment and in the amyloid ascospores; A. nigrocacuminum Flakus, Kukwa & Aptroot sp. nov. that differs from A. megochroleucum in having fused, eccentric ostioles and black (UV−) tops of the pseudostromata; A. pallidoflavum Flakus & Aptroot sp. nov. that differs from A. cinnamomeum in having wider ascospores; A. pyrenuliforme Flakus & Aptroot sp. nov. that differs from A. ecuadoriensis ecuadoriense in having shorter ascospores and in the presence of pseudocyphellae; A. subscoria Flakus & Aptroot sp. nov. that differs from A. scoria in having non-aggregated ascomata; A. variabile Flakus & Aptroot sp. nov. that differs from A. ochroleucoides in the longer ascospores; Bathelium boliviense Flakus & Aptroot sp. nov. that differs from B. lineare in the presence of isohypocrellin inside the pseudostromata; B. flavostiolatum Flakus & Aptroot sp. nov. that differs from all other Bathelium species in the presence of lichexanthone near the ostioles (tops of pseudostromata UV+ yellow) and an orange (K+ carmine red) pigment inside the pseudostromata, the absence of lichexanthone in the thallus, an inspersed hamathecium, and 13–17-septate ascospores; B. inspersomastoideum Flakus & Aptroot sp. nov. that differs from B. mastoideum in having an inspersed hamathecium; B. mirabile Flakus, Kukwa & Aptroot sp. nov. that differs from other Bathelium species in the pseudostromata containing isohypocrellin inside and parietin outside; B. pruinosum Flakus, Kukwa & Aptroot sp. nov. that differs from Astrothelium ochroleucoides in having 8-spored asci, shorter ascospores, an inspersed hamathecium, and an unidentified anthraquinone (orange pigment K+ carmine red) inside the pseudostromata; Constrictolumina chiquitana Flakus, Kukwa & Aptroot sp. nov. that differs from other known Constrictolumina species in having brown and 1-septate to submuriform ascospores; Dictyomeridium lueckingii Flakus & Aptroot sp. nov. that differs from D. proponens in having smaller and less septate ascospores; Polymeridium xanthoexcentricum Flakus & Aptroot sp. nov. that differs from P. alboflavescens in having mostly eccentric ostioles; Pseudopyrenula flavosuperans Flakus & Aptroot sp. nov. that differs from P. superans in having a hamathecium inspersed with yellow oil globules; Trypethelium astroideum Flakus & Aptroot sp. nov. that differs from T. subeluteriae in having K+ carmine red pseudostromata containing parietin inside and black tops with an additional unidentified anthraquinone (rust-red pigment K+ purple, UV−) on the outside, partly fused ostioles, and larger ascospores; and T. xanthoplatystomum Flakus & Aptroot sp. nov. that differs from T. platystomum in the presence of lichexanthone in the thallus.