Working Key to Corticolous Species of Porina
1a. Thallus with isidia; perithecia sometimes present ...................................................2
1b. Thallus with perithecia only.....................................................................................4
2a. Isidia broadly squamiform ........................................................Porina squamulosa
2b. Isidia cylindrical.......................................................................................................3
3a. Perithecia present, wart-shaped to hemispherical; ascospores 7-septate, 40-
50 x 6-8 um (if ascospores 17-21-septate and about 100 x 4 um, cf. Porina
exasperatula)
...................................................................................................... Porina conspersa
3b. Perithecia absent ............................................................................... Porina distans
4a. Ascospores transversely septate...............................................................................5
4b. Ascospores muriform.............................................................................................31
5a. Ascospores 3-7-septate ............................................................................................6
5b. Ascospores irregularly (7-)9-21-septate ................................................................16
6a. Ascospores 3-septate, 25-30 x 4-5 um; perithecia wart-shaped to subglo-
bose, with bumpy surface and broad black spot around ostiole ...Porina melanops
6b. Ascospores (5-)7-septate, (25-)30-70 x (4-)5-14 um; perithecia variable ...............7
7a. Ascospores (4-)5-7 um broad...................................................................................8
7b. Ascospores 8-14 um broad.....................................................................................14
8a. Thallus shiny, with dark, shiny prothallus; perithecia conical to wart-sha-
ped, with narrow brown-black spot around ostiole..................................................9
8b. Thallus usually matt and lacking distinct prothallus; perithecia wart-sha-
ped to hemispherical or subglobose, with pale to brown spot around osti-
ole or perithecia uniformely colored......................................................................10
9a. Ascospores 25-35 um long; thallus usually yellowish......................Porina curtula
9b. Ascospores 40-50 um long; thallus usually greenish...................Porina tetracerae
10a. Ascospores irregularly 7-9-septate, 40-45 um long; perithecia subglobose,
with bumpy surface; thallus coarsely verrucose ............................Porina simulans
10b. Ascospores (5-)7-septate, 25-45 um long; perithecia wart-shaped to hemi-
spherical, rarely subglobose, with smooth surface; thallus smooth to finely
verrucose ................................................................................................................11
11a. Perithecia with pale to redbrown spot around ostiole............................................12
11b. Perithecia uniformely colored................................................................................13
12a. Ascospores 25-35 x 4-5 um; perithecia hemispherical ... Porina “pseudepiphylla”
12b. Ascospores 35-45 x 5-6 um; perithecia hemispherical to wart-shaped .....................
..................................................................................................Porina cryptostoma
13a. Perithecia wart-shaped, with broad brown spot around ostiole; thallus un-
even, slightly shiny .........................................................................Porina africana
13b. Perithecia wart-shaped to subglobose, with pale to redbrown spot around
ostiole; thallus finely verrucose .................................................. Porina subnucula
14a. Thallus matt, minutely verrucose, lacking prothallus; perithecia wart-sha-
ped to subglobose.............................................................................. Porina nucula
14b. Thallus shiny, smooth to uneven, with shiny, dark prothallus; perithecia
lens-shaped to wart-shaped ....................................................................................15
15a. Perithecia wart-shaped, with dark brown spot around ostiole .......Porina imitatrix
15b. Perithecia lens-shaped, with black spot around ostiole ...............Porina mastoidea
16a. Ascospores 4-5 um broad.......................................................................................17
16b. Ascospores 7-20 um broad.....................................................................................23
17a. Perithecia with brown-black spot around ostiole; thallus usually with
shiny, dark prothallus; isidia sometimes present ...................................................18
17b. Perithecia with orange-red to red-brown spot around ostiole; thallus
lacking prothallus; isidia always absent; ascospores variously septate .................19
18a. Ascospores 7-11-septate, 40-50 um long...........................Porina “subtetracerae”
18b. Ascospores 17-21-septate, 100-110 x 4-5 um......................... Porina exasperatula
19a. Ascospores (7-)9-13-septate, 40-70 um long.........................................................20
19b. Ascospores 15-19-septate, 70-120 um long...........................................................21
20a. Perithecia subglobose, with bumpy surface...................................Porina simulans
20b. Perithecia hemispherical to wart-shaped, with smooth surface .................................
...................................................................................... Porina “subdolichophora”
21a. Ascospores 15-septate; perithecia lens-shaped to hemispherical
................................................................................................ Porina dolichophora
21b. Ascospores irregularly 15-19-septate; perithecia hemispherical to wart-
shaped ....................................................................................................................22
22a. Perithecia wart-shaped, with orange-red spot around ostiole; ascospores
15-17-septate, 80-90 um long ........................................Porina “rhodostomoides”
22b. Perithecia hemispherical to wart-shaped, with pale to red-brown spot
around ostiole; ascospores 17-19-septate, 90-100 um long
..........................................................................................Porina aff. dolichophora
23a. Perithecia wart-shaped to subglobose, often with bumpy surface; thallus
usually matt, lacking prothallus, often finely verrucose ........................................24
23b. Perithecia lens-shaped to hemispherical, usually smooth; thallus usually
shiny and usually with dark, shiny prothallus (rarely white or absent),
smooth to uneven or rarely coarsely verrucose......................................................27
24a. Ascospores 7-10 um broad........................................................ Porina guaranitica
24b. Ascospores 10-15 um broad...................................................................................25
25a. Ascospores 11-15-septate, 70-90 um long; perithecia with pale red-brown
spot around ostiole or spot absent............................................... Porina americana
25b. Ascospores 9-11-septate, 50-75 um long; perithecia with red-brown to
black spot around ostiole .......................................................................................26
26a. Perithecia wart-shaped (to subglobose), with smooth to uneven surface
and broad black spot around ostiole................................................ Porina tijucana
26b. Perithecia subglobose, with bumpy surface and red-brown spot around
ostiole..........................................................................................Porina rudiuscula
27a. Perithecia with dark spot around ostiole; dark shiny prothallus usually
present; ascospores 10-15 um broad ......................................................................28
27b. Perithecia lacking dark spot; dark prothallus usually absent; ascospores
15-20 um broad ......................................................................................................30
28a. Perithecia with grey-brown spot and pale ring around ostiole and often
with radiate cracks; thallus rough, as if pseudocyphellate; ascospores 70-
100 um long ................................................................ Porina “pseudocyphellata”
28b. Perithecia with broad black spot around ostiole; thallus shiny; ascospores
60-85 um long ........................................................................................................29
29a. Thallus coarsely verrucose.......................................................Porina internigrans
29b. Thallus smooth......................................................................Porina submastoidiza
30a. Thallus coarsely verrucose, often with white prothallus; ascospores 60-85
um long ....................................................................................... Porina “areolata”
30b. Thallus smooth, lacking prothallus; ascospores 80-100 um long .Porina “elegans”
31a. Thallus shiny, with dark, shiny prothallus, smooth to uneven; perithecia
lens-shaped to hemispherical ..................................................... Porina eminentior
31b. Thallus usually matt and lacking prothallus, often finely verrucose;
perithecia hemispherical to subglobose .................................................................32
32a. Ascospores submuriform, 15-20 um broad............................. Porina nuculastrum
32b. Ascospores richly muriform, 20-30 um broad.......................................................33
33a. Perithecia hemispherical; ascospores 65-75 x 20-25 um......Porina “subfarinosa”
33b. Perithecia wart-shaped to subglobose; ascospores 80-125 x 25-30 um
......................................................................................................... Porina farinosa
