taxonID	type	description	language	source
0FE30F2CBE515498BF00D949FFB4ECE8.taxon	description	Fig. 2	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
0FE30F2CBE515498BF00D949FFB4ECE8.taxon	diagnosis	Diagnosis. Differs from Rhytidhysteron rufulum in its host (Bignoniaceae), size of ascomata (2.5 - 3.5 x 1.1 - 1.5 x 1.0 - 1.9 mm), asci (182 - 191 x 12 - 13 μm) and its reaction with KOH being faster (one to five seconds).	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
0FE30F2CBE515498BF00D949FFB4ECE8.taxon	materials_examined	Type. Holotype: Mexico. Quintana Roo, Cozumel Municipality, San Gervasio Chen-tuk archaeological zone, 20 ° 29 ' 50 " N, - 86 ° 50 ' 39 " W, 0 m a. s. l., 21 January 2018, A. Cobos-Villagran 951 (ENCB), on Tabebuia rosea DC. (Bignoniaceae), GenBank: LSUMW 9394459, ITSMZ 056797, tef 1 MZ 457338.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
0FE30F2CBE515498BF00D949FFB4ECE8.taxon	description	Description. Ascomata hysterothecial to apothecial 2.5 - 3.5 mm long, 1.1 - 1.5 mm wide, (0.8) 1.0 - 1.9 mm high, erumpent, solitary, boat-shaped hysterothecia, subglobose, elongated, compressed in the apex, with conspicuous longitudinal groove or cleft and becoming lenticular when mature or exposed to moisture, black, carbonaceous when dry. Margin involute, smooth to perpendicularly slightly striated, black. Exciple integrated in two layers, the first carbonaceous, glabrous, 45 - 100 μm thick, wide at the base, composed of pseudoparenchymal cells of textura prismatica (iso-radiating cells), thick-walled, the second composed of cells hyaline, thin-walled. Pseudoparaphyses up to 2.5 μm wide, filamentous, capitate, hyaline, septate, enclosed in a gelatinous matrix, strongly anastomosed above the asci. Epithecium reddish brown (8 F 7) when fresh, black in old specimens or when dry, becoming greyish magenta (13 B 5) in the presence of 10 % KOH. Asci 182 - 191 x 12 - 13 μm, bitunicate, cylindrical, hyaline, uniseriate, octosporic, thick-walled, with a sinuous base. Ascospores 26 - 29 (- 31) x 9 - 11 (- 13) μm, (x ̄ = 28 x 10.2 μm, n = 30), ellipsoidal to fusiform, rounded at both ends, dark brown in colour with three transverse septa, with a thick and smooth wall.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
0FE30F2CBE515498BF00D949FFB4ECE8.taxon	distribution	Distribution. Known from a single local Island in the Cozumel Biosphere Reserve, Mexico.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
0FE30F2CBE515498BF00D949FFB4ECE8.taxon	etymology	Etymology. The epithet refers to the Island in the Cozumel Biosphere Reserve where the species was found.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
0FE30F2CBE515498BF00D949FFB4ECE8.taxon	materials_examined	Specimens examined. Mexico, Quintana Roo, Cozumel Municipality, San Gervasio Chen-tuk archaeological zone, 20 ° 29 ' 54 " N, - 86 ° 50 ' 43 " W, 13 m a. s. l., 21 January 2018, T. Raymundo 7321, R. Valenzuela 17985 (ENCB); 17 June 2018, A. Cobos-Villagran 1838 (ENCB).	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
D90B3B73DC8B5D27A3392DE8873D01D8.taxon	description	Fig. 3	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
D90B3B73DC8B5D27A3392DE8873D01D8.taxon	diagnosis	Diagnosis. Different from most Rhytidhysteron species by having greyish-green ascomata with greenish-grey to yellow epithecium in the presence of KOH, and large and wide ascospores (45 - 47 x 17 - 19 μm).	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
D90B3B73DC8B5D27A3392DE8873D01D8.taxon	materials_examined	Type. Holotype: Mexico. Oaxaca, Sierra de Juarez, Chinantla, Santiago Comaltepec Municipality, La Esperanza, Carretera Oaxaca-Tuxtepec Km 51, 17 ° 37 ' 55 " N, - 96 ° 22 ' 01 " W, 1600 m a. s. l., 23 May 2017, T. Raymundo 6579 (ENCB). GenBank: LSUMW 9394457, ITSMZ 056795.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
D90B3B73DC8B5D27A3392DE8873D01D8.taxon	etymology	Etymology. The epithet refers to the locality " La Esperanza " where the species was found.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
D90B3B73DC8B5D27A3392DE8873D01D8.taxon	description	Description. Ascomata hysterothecial to apothecial, (2 -) 3 - 4.5 mm long, (1.2 -) 2 - 3 mm wide, (1 -) 1.7 - 2.4 mm high, superficial, solitary, rarely gregarious, boat-shaped hysterothecia, elongated, straight or flexuous, with sharp ends, opening in a discoid shape when ripe or with humidity, exposing the hymenium, taking the apothecial shape of 3 - 4 mm in diameter, brown (6 D 7), dull-green (30 E 4) to black. Margin involute, perpendicularly striate, greyish green (30 C 4) to dull green (30 D 4). Exciple integrated in two layers, the first carbonaceous, glabrous, 60 - 220 μm wide, thinning in the apical part, the middle part and the base are thicker, composed of pseudoparenchymal cells of textura globulosa-angularis (isodiametric cells), 11 x 10 μm, thick-walled, 3 μm wide, the second slightly pigmented to hyaline, thin-walled. Pseudoparaphyses up to 4 μm wide, filamentous, capitate, apical part wider, straight, hyaline, with a septum, enclosed in a gelatinous matrix, strongly anastomosed above the asci. Epithecium dark green (30 F 4) to black, becoming yellow (2 A 7) in the presence of 10 % KOH. Asci (250 -) 265 - 270 x (18 -) 19 - 20 μm, bitunicate, cylindrical, rounded apex, hyaline, uniseriate, octosporic, thick-walled, with a short pedicel. Ascospores of (42 -) 45 - 47 (- 49) x (15 -) 17 - 19 (- 23) μm, (x ̄ = 45 x 17.2 μm, n = 30), ellipsoidal to spindle-shaped, rounded or pointed at both ends, reddish-brown to brown when mature, with three transverse septa, constricted at the septa, thick-walled and smooth.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
D90B3B73DC8B5D27A3392DE8873D01D8.taxon	distribution	Distribution. Known from a single locality in a forest in La Esperanza, Mexico.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
D90B3B73DC8B5D27A3392DE8873D01D8.taxon	materials_examined	Specimens examined. Mexico. Oaxaca. Sierra de Juarez, Santiago Comaltepec Municipality, La Esperanza, Carretera Oaxaca-Tuxtepec Km 51, 17 ° 37 ' 55 " N, - 96 ° 22 ' 01 " W, 1600 m a. s. l., 22 May, 2017, R. Valenzuela 17206 (ENCB); 23 May 2017, A. Cobos-Villagran 498 (ENCB); 25 May 2017, E. Campero 3 (ENCB), 30 April 2018, A. Cobos-Villagran 1119 (ENCB), A. Gay AG 30041814 (ENCB).	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
DFC24A9BFC9D52E8BDB980345652D3E4.taxon	description	Fig. 4	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
DFC24A9BFC9D52E8BDB980345652D3E4.taxon	diagnosis	Diagnosis. Differs from Rhytidhysteron rufulum by its green-yellowish pruina on the margins, size of asci (267 - 282 x 15.5 - 16 μm) and larger ascospores (40 - 44 x 12 - 14 μm).	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
DFC24A9BFC9D52E8BDB980345652D3E4.taxon	materials_examined	Type. Molango de Escamilla Municipality, Laguna Atezca, 20 ° 48 ' 32 " N, - 98 ° 44 ' 52 " W, 1281 m a. s. l., 01 June 2018, A. Trejo 74 (ENCB). GenBank: LSUMW 9394461, ITSMZ 056799.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
DFC24A9BFC9D52E8BDB980345652D3E4.taxon	etymology	Etymology. The epithet refers to the type of vegetation (mountain mesophilic forest) it was collected from.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
DFC24A9BFC9D52E8BDB980345652D3E4.taxon	description	Description. Ascomata hysterothecial to apothecial, 2.5 - 4 mm long, 1.0 - 1.5 mm wide, 1.4 - 1.7 mm high, superficial or erumpent, gregarious, rarely solitary, with small hysterothecial ascomata, ellipsoid to oblong and black when young, then boat-shaped hysterothecia, with some constriction in the middle part, flexuous, open in apothecioid ascomata, dark green (30 F 3 - 4), dull green (30 E 3 - 4), greyish green (30 E 6 - 7), deep green (30 D-E 8) to yellowish green (30 B-C 8) when mature, forming small ascomata within disc in old specimens. Margin involute, perpendicularly striate, marks are not roughness, rather irregular slits, with yellowish green (30 B-C 8) pruina. Exciple integrated in two layers, the first carbonaceous, glabrous, green yellowish, 62.5 - 75 μm thick, in the middle part widening more (112.5 - 125 μm), composed of pseudoparenchymal cells of textura prismatica (iso-radiating cells), the second composed of cells hyaline, thin-walled. Pseudoparaphyses 2.0 - 2.5 μm up to 3.0 μm wide, filamentous, capitate, hyaline, without septa, branched towards the apex, enclosed in a gelatinous matrix, strongly anastomosed above the asci. Epithecium reddish orange (7 B 8) to orange red (8 A 8), becoming greyish magenta (13 D 6) in the presence of 10 % KOH. Asci 267 - 282 x 15.5 - 16 μm, bitunicate, cylindrical, hyaline, uniseriate, octosporic, thick-walled, with a sinuous base. Ascospores (38 -) 40 - 44 (- 46) x 12 - 14 μm, (x ̄ = 44.2 x 13.6, n = 30), ellipsoidal to oblong, light brown in colour, with three transverse septa, constricted at the septa, with a thick and smooth wall.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
DFC24A9BFC9D52E8BDB980345652D3E4.taxon	distribution	Distribution. Known from a single locality in Laguna de Atezca, Molango de Escamilla, Hidalgo, Mexico.	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
DFC24A9BFC9D52E8BDB980345652D3E4.taxon	materials_examined	Specimens examined. Mexico. Hidalgo, Molango de Escamilla Municipality, Laguna Atezca, 20 ° 48 ' 32 " N, - 98 ° 44 ' 52 " W, 1281 m a. s. l., 01 June 2018; C. Herrera 40 (ENCB), A. Cobos-Villagran 1800 (ENCB).	en	Cobos-Villagran, Aurora, Valenzuela, Ricardo, Hernandez-Rodriguez, Cesar, Calvillo-Medina, Rosa Paulina, Villa-Tanaca, Lourdes, Mateo-Cid, Luz Elena, Perez-Valdespino, Abigail, Martinez-Gonzalez, Cesar Ramiro, Raymundo, Tania (2021): Three new species of Rhytidhysteron (Dothideomycetes, Ascomycota) from Mexico. MycoKeys 83: 123-144, DOI: http://dx.doi.org/10.3897/mycokeys.83.68582, URL: http://dx.doi.org/10.3897/mycokeys.83.68582
