[ticolichen-Logo] provisional
determination keys
for the Graphidales
of Costa Rica
[bgbm-Logo] [graphidales-Logo] by H. Sipman
last updated:
18 August 2008
other webkeys
other Zschackia issues
intro - genera - Acanthothecis - Anomomorpha - Aulacographa - Carbacanthographis - Diorygma - Dyplolabia - Fissurina - Glyphis - Graphis - Hemithecium - Leiorreuma - Phaeographis - Phaeographopsis - Platygramme - Platythecium - Sarcographa - Thalloloma - Thecaria -
corticolous Thelotremataceae


The keys presented on this website are based on recent literature (see list below) and the study of several hundreds of Costarican lichen samples. The descriptions are based on Costa Rican specimens, unless otherwise stated. In that case the descriptions may be incomplete and lack, e.g. some spore characteristics. Hymenium inspersion is then supposed to be absent.
Since the classification of the tropical graphidales is still very poorly known, much uncertainty remains about the delimitation and naming of the taxa used, in particular at species level. It is the hope of the author that the keys will contribute to the development of a better classification of the group.
The current generic delimitation of the Thelotremataceae is particularly unsatisfactory. Therefore the species of this family are treated in a single key. Awaiting a new classification to be proposed soon by Andreas Fritsch, the species are provisionally attributed to the genus where they have been included most recently.
The voucher specimens for the photographs are kept in B, except: leg. Aptroot in herb. Aptroot.
The colours of the pictures may deviate from the natural colours, because they are taken with artificial light, often from several years old herbarium specimens.
These keys are prepared in the frame of the TICOLICHEN project.

Hale, M.E. 1974: Morden-Smithsonian Expedition to Dominica: The lichens (Thelotremataceae). - Smithsonian Contrib. Bot. 16: 1-46.
Hale, M.E. 1978: A revision of the lichen family Thelotremataceae in Panama. - Smithsonian Contrib. Bot. 38: 1-60.
Hale, M.E. 1980: Generic delimitation in the lichen family Thelotremataceae. - Mycotaxon 11: 130-138.
Hale, M.E. 1981: A revision of the lichen family Thelotremataceae in Sri Lanka. - Bull. British Museum (Nat. Hist.), Botany Ser. 8: 227-332.
Kalb, K. & Staiger, B. 2000: Dyplolabia Massalongo, Monographie einer vergessenen Flechtengattung. - Hoppea 61: 409-422.
Kalb, K. 2004: New or otherwise interesting lichens II. Biblioth. Lichenol. 88: 301-329.
Kalb, K., Staiger, B. & Elix, J.A. 2004: A monograph of the lichen genus Diorygma - a first attempt. Symb. Bot. Ups. 34(1): 133-181.
Staiger, B. & Kalb, K. 1999: Acanthothecis and other graphidioid lichens with warty periphysoids or paraphysis-tips. - Mycotaxon 73: 69-134.
Staiger, B. 2002: Die Flechtenfamilie Graphidaceae. Studien in Richtung einer natürlicheren Gliederung. - Bibliotheca Lichenologica, 85, J. Cramer, Berlin, Stuttgart. 526 pp.
Wirth, M. & Hale, M.E. 1963: The lichen family Graphidaceae in Mexico. - Contrib. U.S. Natl. Herb. 36(3): 63-119.
Wirth, M. & Hale, M.E. 1978: Morden-Smithsonian Expedition to Dominica: the lichens (Graphidaceae). - Smithsonian Contributions to Botany 40: 1-64.

Key to the GENERA OF GRAPHIDACEAE / Key to the corticolous SPECIES OF THELOTREMATACEAE in Costa Rica

1A Ascocarps with carbonized parts visible in surface view or in cross section - - - 2
Ascocarps without carbonized parts - - - 14

2A Hymenium inspersed with oil-like droplets ca. 1(-5) mu in diam. - - - 3
Hymenium clear - - - 8

3A Ascospores colourless, I+ dark violet - - - Graphis
Ascospores grey, I+ purplish when young, becoming dark brown with age - - - 4

4A Ascocarps single, unbranched to stellate - - - 5
Ascocarps aggregated in pseudostromas, densely branched and/or intertwined, or with fissured disc - - - Sarcographa

5A Ascocarps with thick carbonized lateral excipulum and/or hypothecium - - - 6
Ascocarps with thinly carbonized or uncarbonized excipulum - - - 7

6A Carbonisation mainly in lateral exciple; Graphis-like though usually with exposed disc - - - Platygramme
Carbonisation mainly in hypothecium; ascocarps raised with thick, pale margins - - - Thecaria

7A Ascocarps with thick, carbonized hypothecium, becoming very prominent with age - - - Leiorreuma
Ascocarps with thin, not or slightly carbonized hypothecium, hardly raised above the thallus surface with age - - - Phaeographis

8A (2) Carbonization restricted to a thin layer in the lateral excipulum; ascocarps slit-like, with sunken, usually hidden disc - - - Fissurina
Carbonisation throughout the lateral excipulum, sometimes restricted to the apical part, sometimes also in the hypothecium; ascocarps not slit-like but either with firmly closed excipular labiae or with exposed disc - - - 9

9A Ascospores hyaline only when young, later pale grey to grey, often becoming dark brown when old - - - 10
Ascospores continuously hyaline - - - 11

10A Ascospores hyaline for much of their development, I+ blueviolet, for a while with very thick outer walls much thicker than the septa, finally pale grey with thin outer walls - - - Aulacographa
Ascospores hyaline only when young, soon pale grey to grey, I+ purplish, with outer walls about as thick as septa, becoming dark brown when old - - - Phaeographis

11A Ascospores I-negative - - - 12
Ascospores I+ dark violet to dark brown-violet - - - 13

12A Ascospores variously septate; ascocarps C- - - - Carbacanthographis
Ascospores 3-septate; ascocarps covered with white, C+ red layer - - - Dyplolabia

13A Disc usually exposed, with brown powdery cover; paraphyses anastomosing, with 2-3 mu thick walls - - - Glyphis
Disc usually not visible, without brown powdery cover; paraphyses hardly anastomosing, with thin walls much thinner than lumina - - - Graphis

14A (1) Hymenium inspersed with oil-like droplets ca. 1-5 mu in diam. - - - 15
Hymenium clear - - - 17

15A Ascocarp margins thick, uncarbonized; disc invisible - - - "Hemithecium"
Ascocarp walls thin, often slightly carbonized, or low; disc exposed - - - 16

16A Ascospores grey, brown when old - - - Phaeographis
Ascospores colourless (cf. also Fissurina cf. nitidescens) - - - Anomomorpha

17A Hymenium jelly tough and paraphyses not spreading when a section is squashed; paraphyses with indistinctly delimited, thick, gelatinized walls, only lumina visible in sections; thallus surface dull, without cortex - - - 18
Hymenium jelly soft and paraphyses easily spreading when squashing; paraphyses with distinct, thin walls thinner than the lumina; thallus surface mostly slightly shiny and with cortex - - - 19

18A Disc with whitish powdery cover or flesh-coloured to pale brown - - - Diorygma
Disc brown or purplish to black - - - "Thalloloma"

19A Paraphyse tips warty to spinulose - - - 20
Paraphyse tips smooth - - - 21

20A Ascospores 3-septate - - - Fissurina
Ascospores pluriseptate - - - Acanthothecis

21A Ascospores grey, dark brown with age - - - 22
Ascospores colourless - - - 23

22A Ascospores with rounded lumina, variously septate, usually with more than 3 septa, over 14 mu long; thallus surface slightly shiny and with cortex - - - Phaeographis
Ascospores with cylindrical lumina, 3-septate, up to ca. 13 mu long; thallus surface dull, without cortex - - - Phaeographopsis

23A Ascocarp margins prominent, raised above and often covering the disc, often swollen and grooved; ascospores I+ or I- - - - 24
Ascocarp margins low, hardly exceeding the widely visible disc; ascospores I+ violet - - - 25

24A Ascospores I- or I+ pale bluish, often 3-septate - - - Fissurina
Ascospores I+ dark violet, always with more than 3 septa - - - Hemithecium

25A Hypothecium becoming thick with age; ascocarps finally strongly raised above the thallus - - - Platythecium
Hypothecium thin; ascocarps remaining flush with thallus - - - Thalloloma

The species of Acanthothecis in Costa Rica

1A Ascospores muriform - - - Acanthothecis hololeucoides
Ascospores transversely septate - - - Acanthothecis subclavulifera

Acanthothecis hololeucoides (Nyl.) Staiger & Kalb - Ascocarps rounded to oval, 1-3 x 0.6-1 mm, with swollen, crenate margins, with more or less exposed disc; hymenium 100-130 mu; ascospores 2-8/ascus, 50-90(-90) x 12-19 mu, 20-35 x 2-4 celled; protocetraric acid present. Specimens studied: Sipman 51576, 53295, 53405B.
[A. hololeucoides]
Costa Rica (Sipman 51796); picture length = 7 mm.

Acanthothecis subclavulifera Staiger & Kalb - Ascocarps ca. 3-5 x 0.5-0.7 mm; hymenium 120-160 mu; ascospores 4-8/ascus, ca. 70-90 x 10-12(-16) mu, transversely septate, 20-30-celled. Specimens studied: Sipman 48136k, 51039A, 51979, 52041.
[A. subclavulifera] [A. subclavulifera]
Costa Rica (Sipman 51039A); picture length = 7 mm. Costa Rica (Sipman 51045D); picture length = 7 mm.

The species of Anomomorpha in Costa Rica

1A Thallus with schizidia-covered, ca. 1 mm tall and wide warts; ascocarps short and much raised - - - Anomomorpha "tuberculatum"
Thallus without prominent warts, without schizidia; ascocarps elongate and initially level with thallus - - - Anomomorpha sordida

Anomomorpha sordida Staiger - Ascocarps ca. 0.5-3.5 x 0.2-0.7 mm, with covered or exposed disc; hymenium 60-90 mu; ascospores 8/ascus, transversely septate, occasionally submuriform, I+ violet, (8-)10-12 x 4.5-6.5 mu, 4-(x 1-2) celled. Specimen studied: Aptroot 60440.
[A. sordida]
Brazil (Kalb, Lich. Neotrop. 371); picture length = 7 mm.

Anomomorpha "tuberculata" - Ascocarps roundish and deeply lobed, strongly raised, with ca. 0.5 mm wide lobes; margins forming a low thalloid rim around the exposed, pinkish, flat disc; hymenium 60 mu, inspersed; ascospores 8/ascus, submuriform, ca. 6-10 x 6 mu, 3 x 1-2 celled. Protocetraric acid present. Specimens studied: Sipman 48109C, 51789. Also available in B from the Tepui area of Guyana and Venezuela.
[A. tuberculata] [A. tuberculata]
in prep.

The species of Aulacographa in Costa Rica

1A Ascocarps 0.2-0.3 mm wide - - - Aulacographa elegans
Ascocarps 0.4-0.6 mm wide - - - Aulacographa "pittierii"

Aulacographa elegans (Sm.) Leight. - Thallus thin, whitish. Ascocarps elongate, (1-)2-5 mm long. longer sections usually brooken in 1-2 mm long parts and 0.4-0.6 mm wide, occasionally branched, semi-exserted; labiae black, without thalline cover, in larger ascocarps once or a few times sulcate; hymenium c. 120 mu, clear; ascospores 8/ascus, transversely septate, in hyaline stage with swollen lateral walls I+ dark-violet 50-60 x12-14 mu, when old pale grey, I-, c. 14-celled. Specimens studied: France, Sipman 14531, 14776. No CR specimens studied by this author.
[A. elegans] [A. elegans]
France, Sipman 14531; picture length = 7 mm. France, Sipman 14531; hymenium with juvenile, thinwalled (left), old, grey (right) and thickwalled spores (upper right) picture length = 100 mu.

Aulacographa "pittierii" - Thallus thin, whitish. Ascocarps elongate, 1-2 mm long and 0.2-0.3 mm wide, occasionally branched, sessile with somewhat constricted base; labiae black, without thalline cover, in larger ascocarps once or a few times sulcate; hymenium c. 135 mu, clear; ascospores 8/ascus, transversely septate, in hyaline stage with swollen lateral walls I+ dark-violet ca. 40 x 20 mu, when old pale grey, I-, ca. 50 x 14 mu, 12-celled. Specimen studied: Aptroot 60981. NOTE: Reminiscent of Graphis species with "Melaspilea"-type ascocarps like G. ruiziana, but deviating by the ascospores with swollen lateral walls, finally grey, and ca. 2 mu thick, short-celled paraphyses typical of Aulacographa.
in prep.

The species of Carbacanthographis in Costa Rica

Carbacanthographis marcescens (Fée) Staiger & Kalb (Graphina marcescens (Fée) Müll. Arg.) - Ascocarps ca. 3-5 x 0.2-0.3 mm, with whitish powdery cover; hymenium 80-100 mu; ascospores 8/ascus, ca. 13-15 x 7-8 mu, muriform, 4-6 x 1-2 celled, juv. with thick central septum. Specimens studied: Sipman 46566, 46568.
[C. marcescens] [C. marcescens]
Costa Rica (Sipman 46566); picture length = 7 mm. Costa Rica (Sipman 46568); picture length = 7 mm.
[C. marcescens] [C. marcescens]
Costa Rica (Sipman 53268); picture length = 7 mm. id., young and ripe spores in asci; note angular thickening of primary septum in young spores; picture length = 130 mu.

The species of Dyplolabia in Costa Rica

Dyplolabia afzelii (Ach.) A. Massal. (Graphis afzelii Ach.) - Ascocarps ca. 3-5 x 0.5-0.7 mm; hymenium 90-100 mu; ascospores 8/ascus, 16-22 x 7-10 mu, transversely septate, 4-celled. Specimens studied: Sipman 48163L, 48382K. NOTE: The available specimens lack ascospores and therefore the identification is tentative.
[D. afzelii] [D. afzelii]
Costa Rica (Sipman 48382K); picture length = 7 mm. Costa Rica (Sipman 48163L); picture length = 7 mm.

The species of Glyphis in Costa Rica

1A Ascocarps elongate, Graphis-like with disc reduced to fissure - - - Glyphis substriatula
Ascocarps rounded, with one or more brownish, rounded or elongate discs - - - 2

2A Ascocarps with single disc, rounded, apothecium-like - - - Glyphis scyphuliferum
Ascocarps with several discs embedded in raised brown stroma-like body - - - Glyphis cicatricosa

Glyphis cicatricosa Ach. - Hymenium 70-100 mu, clear; ascospores 8/ascus, transversely septate, colourless, I+ violet, 28-60 x 7-10 mu, 8-13-celled.
[G. cicatricosa] [G. cicatricosa]
El Salvador (Sipman 37897); picture length = 7 mm. El Salvador (Sipman 38030); picture length = 7 mm.

Glyphis scyphuliferum (Gyrostomum scyphuliferum Nyl.) - Hymenium 90-130 mu, clear; ascospores 8/ascus, muriform, colourless, I+ weakly brown-violet, 30-45 x 12-16 mu, 8-13 x 3-4 celled.
[G. scyphuliferum] [G. scyphuliferum]
El Salvador (Sipman 38031); picture length = 7 mm. Costa Rica (Sipman 51739); picture length = 7 mm.

Glyphis substriatula (Nyl.) Staiger - Hymenium 100-140 mu, clear; ascospores 8/ascus, muriform, colourless, I+ violet, ca. 45 x 12-17 mu, 12-14 x 4 celled. Specimens studied: Sipman 52061, 51009E.
[G. substriatula] [G. substriatula]
Costa Rica (Sipman 52061); picture length = 7 mm. id., detail showing brown, linear disc; picture length = 3.5 mm.
[G. substriatula]
Costa Rica (Sipman 51009E), old plant with dense ascocarps; picture length = 7 mm.