[ticolichen-Logo] provisional
determination keys
for the Graphidales
of Costa Rica
[bgbm-Logo] [graphidales-Logo] by H. Sipman
BGBM
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

Acanthotrema, Ampliotrema, Chapsa, Gyrotrema, Fibrillithecis, Leptotrema, Leucodecton, Melanotrema, Myriotrema, Ocellularia, Ramonia?, Redingeria, Reimnitzia, Stegobolus, Thelotrema

The species of Thelotrema in Costa Rica


Thelotrema adjectum Nyl. - Thallus pale tannish or whitish grey, over 5 cm diam., epiphloeodal, grainy to minutely verruculose, continuous, surface shiny, with distinct, not filmy cortex, not oily; medulla indistinct, whitish; ascocarps immersed in the thallus or in slightly raised, 0.6-1.0 mm wide warts with semi-erect, jagged margin and 0.2-0.3 mm wide pore filled by the free, flesh-coloured inner excipulum; hymenium ? mu, clear; spores hyaline, muriform, 8/ascus, I-, ca. 35-50 x 12-15 mu, ca. 8-12 x 1-2 celled; chemistry: no substance. NOTE: Description after Hale (1978). Not yet known from Costa Rica, but reported from Panama (Hale 1978).
[T. adjectum] [T. adjectum]
Florida (Harris 23316); picture length = 4 mm. El Salvador (Sipman 37885); picture length = 4 mm.

Thelotrema cryptotrema Nyl. - Thallus greenish grey, over 5 cm diam., epiphloeodal, continuous, surface shiny, with distinct, not filmy cortex, not oily; medulla indistinct, whitish; ascocarps immersed in very slightly raised, 1.0-1.4 mm wide warts with 0.2 mm wide, impressed pore with thallus-coloured margin, sometimes showing the free, white inner excipulum; hymenium 250 mu, clear; spores hyaline, muriform, ca. 4?/ascus, I+ pale blue, ca. 60-65 x 25-30 mu, ca. 14 x 5 celled, with thick outer wall and ca. 7 primary septa, with halo; chemistry: psoromic acid. Specimens studied: Sipman 42269.
[T. cryptotrema]
Costa Rica (Sipman 42269); picture length = 3.5 mm.

Thelotrema dissutum (Hale) Hale [Chapsa or Fissurina?] - Thallus greenish, ca. 10 cm diam., epiphloeodal, continuous, surface slightly shiny, with indistinct cortex, oily; medulla indistinct; ascocarps immersed, often triangular, ca. 0.5 mm wide, with pale brownish discs, (sometimes?) aggregated, with margin of usually three incurved to erect slips, without externally visible inner excipulum or forming an inner row of slips; hymenium 60 mu, clear; spores hyaline, transversely septate, 8/ascus, I-negative (pale violet), ca. 15 x 6 mu, 4 celled, with rather thin septa; chemistry: no substance. Specimens studied: Sipman 51103A.
[T. dissutum]
Costa Rica (Sipman 51103A); picture length = 3.5 mm.

Thelotrema esslingeri (Hale) Hale - Thallus greenish grey, over 3 cm diam., epiphloeodal, minutely verruculose, continuous?, surface slightly shiny?, with distinct?, not filmy cortex, not oily; medulla indistinct, whitish; ascocarps immersed in the thallus, 0.7-1.1 mm wide, with thick, erect or slightly recurved, not split, apically pulverulent to subsorediate margin and flesh-coloured, slightly white-pruinose, exposed disc, without externally visible inner excipulum; hymenium ca. 90 mu, clear; spores hyaline, transversely septate, 8/ascus, I+ blue?, ca. 18-21 x 5-6 mu, 5-6 celled; chemistry: unidentified P- compound. NOTE: Description after Hale (1978). Not yet known from Costa Rica, but reported from Panama (Hale 1978).
in prep.

Thelotrema expallescens Nyl. - Thallus pale greenish grey, over 3 cm diam., epiphloeodal, continuous, surface slightly shiny, with distinct, not filmy cortex, not oily; medulla distinct, white; ascocarps immersed in the thallus or in slightly raised, 0.6-1.0 mm wide warts with 0.1-0.4 mm wide, round or elongate pore with pale margin, showing the small, pinkish white disc with free inner excipulum forming a white rim around the disc; hymenium 100 mu, clear; spores hyaline, muriform, 8/ascus, I-negative, ca. 12-15 x 6-7 mu, ca. 4 x 1-2 celled chemistry: stictic acid with associated spots, incl. constictic. Specimens studied: Sipman 37291, 12104 (U), 12174 (U). NOTE: nr. 12104 and 12174 identified by M. Hale, 1980.
[T. expallescens] [T. expallescens]
Costa Rica (Sipman 12174); picture length = 3.5 mm. Costa Rica (Sipman 12104); picture length = 3.5 mm.
[T. expallescens]
Costa Rica (Sipman 47892); picture length = 3.5 mm.

"Thelotrema" glaucopallens Nyl. - Thallus greenish grey, over 5 cm diam., epiphloeodal, continuous, surface shiny, with filmy cortex, not oily; medulla indistinct, whitish; ascocarps immersed in thallus or in very slightly raised, 0.2-0.3 mm wide warts with 0.1 mm wide, white-rimmed pore, without carbonized parts, without externally visible inner excipulum; hymenium 70-120 mu, clear; spores hyaline, muriform, (6-)8/ascus, I-negative, 20-25 x 9-12 mu, 8-10 x 3-4 celled, with thick outer wall, juv. with thin septa; chemistry: tr. norstictic, stictic, tr. cryptostictic, ?constictic acids. Specimens studied: Sipman 48389B, 51166, 51172A, 41985, 42240, 42244, 42314, 51630, Aptroot 60175, 60199, 60139. NOTE: The spores have unusually small cells. Norstictic acid was found as only substance in specimens 48389B, 51166, 51172A. Nr. 60199 and 60139 have additionally menegazziaic acid.
[T. glaucopallens] [T. glaucopallens]
Costa Rica (Sipman 51623); picture length = 3.5 mm. Costa Rica (Sipman 47892); picture length = 3.5 mm.
[T. glaucopallens] [T. glaucopallens]
Costa Rica (Sipman 48389B); picture length = 3.5 mm. Costa Rica (Sipman 48389B); picture length = 3.5 mm.

Thelotrema hypoprotocetraricum (Hale) Hale - Thallus pale creamish white, ca. 2-4 cm diam., epiphloeodal, finally fissured, surface slightly shiny?, with indistinct cortex?, not oily; medulla indistinct; ascocarps single or with 2-3 immersed in slightly to distinctly raised, 0.8-1.4 mm wide warts with thick, rarely erect. apically pulverulent and white margin, with ? mm wide, round pore showing the free inner excipulum rim, without carbonisation or columella; hymenium 310-320 mu, clear; spores grey, muriform, 1-2/ascus, I-negative, ca. 150-210 x 33-36 mu, ca. ? x ? celled (densely muriform); chemistry: hypoprotocetraric and 4-O-demethylnotatic acids. NOTE: Description after Hale (1978). Not yet known from Costa Rica, but reported from Panama (Hale 1978).
in prep.

Thelotrema lepadinum (Ach.) Ach. - Thallus pale greenish grey, over 3 cm diam., epi- to endophloeodal, continuous, surface slightly shiny, with indistinct cortex, not oily; medulla indistinct; ascocarps immersed in distinctly raised, 0.5-1.0 mm wide warts with 0.1-0.5 mm wide, round pore with thallus-coloured margin, showing the pinkish white disc, with free inner excipulum forming a low white rim around the disc; hymenium 120-190? mu, clear; spores hyaline, muriform, 2-4/ascus, I-negative, ca. 50-110 x 20 mu, ca. 17 x 3-4 celled, with thick outer wall; chemistry: no substance. Specimens studied: Sipman 20591, 11609 (U).
[T. lepadinum]
Costa Rica (Sipman 11609); picture length = 3.5 mm.

"Thelotrema" leucomelanum Nyl. (incl. Thelotrema stylothecium Vain.) - Thallus pale tannish grey, 3-10 cm diam., endophloeodal with epiphloeodal cortex or more completely epiphloeodal, continuous, surface slightly shiny, with indistinct to distinct cortex, not oily; medulla indistinct; ascocarps immersed in low, 0.3-0.7 mm wide warts with 0.1-0.5 mm wide, rounded pore showing the grey, wide, carbonized columella with flat top, with carbonized excipulum, without externally visible inner excipulum; hymenium ca. 90-100 mu, clear; spores hyaline, muriform, 8/ascus, I-negative, ca. 25-35 x 12-14(-18) mu, 6-10 x 2-4 celled, juv. with thick septa; chemistry: stictic acid present, or no substance. Specimens studied: Sipman 20444, 48040A, 47818A, 48018H; Kalb Lich. Neotr. 433, Aptroot 60597. NOTE: The species grows on thin, smooth bark.
[T. leucomelanum] [T. leucomelanum]
Costa Rica (Sipman 48032E); picture length = 3.5 mm. Costa Rica (Sipman 48040A); picture length = 3.5 mm.
[T. stylothecium] [T. stylothecium]
Costa Rica (Sipman 51925); picture length = 3.5 mm. Costa Rica (Aptroot 60597); picture length = 3.5 mm.

Thelotrema monosporum Nyl. - Thallus pale tannish grey, ca. 2 cm diam., endophloeodal, continuous, surface slightly shiny, with indistinct cortex, not oily; medulla indistinct; ascocarps immersed in distinctly raised, 0.4-1.0 mm wide warts with 0.2-0.6 mm wide, round pore with erect margin of thallus colour, showing the grey disc, with free inner excipulum forming a low white rim around the disc; hymenium 125-180 mu, clear; spores grey, muriform, 1(-4)/ascus, I-negative or + pale violet, ca. 45-120 x 17-30 mu, ca. 6-30 x 1-8 celled, with thick outer wall; chemistry: no substance. Specimens studied: Sipman 48042E, 51135B, Aptroot 60324. NOTE: superficially very similar to T. pachysporum, but with muriform instead of transversely septate spores. The spores of 48042E have much smaller cells (ca. 16 x 4) than 51135b (6-8 x 1-3).
[T. monosporum] [T. monosporum]
Costa Rica (Sipman 48042E); picture length = 3.5 mm. Costa Rica (Sipman 51135B); picture length = 3.5 mm.
[T. monosporum]
Costa Rica (Aptroot 60324); picture length = 3.5 mm.

Thelotrema neei (Hale) Hale? - Thallus whitish grey, over 5 cm diam., mainly endophloeodal, continuous, surface slightly shiny?, with indistinct cortex?, not oily; medulla indistinct; ascocarps immersed in the thallus, 0.4-0.7 mm wide, with erect or slightly recurved, low, entire thalline margin, with dark rusty or white-pruinose, exposed disc surrounded by a low, free inner excipulum; hymenium 60-70 mu, clear; spores hyaline, transversely septate, 8/ascus, I-negative, ca. 10-14 x 5 mu, 4 celled; chemistry: stictic and constictic acids. Specimens studied: Sipman 51108. NOTE: said to be chroodiscoid, but the picture by Hale shows a lepadinoid structure. Specimen 51108 lacks ascospores and has a 125 mu high hymenium. Description completed with data from Hale (1978).
[T. neei?]
Costa Rica (Sipman 51108); picture length = 3.5 mm.

Thelotrema occlusum Nyl. - Thallus whitish to ivory, 3-8 cm diam., epiphloeodal, continuous, surface shiny, with distinct cortex, not oily; medulla indistinct; ascocarps immersed in slightly raised, 0.6-1.0 mm wide warts with 0.2-0.4 mm wide, round, white-rimmed pore filled by the free inner excipulum, without carbonisation or columella; hymenium ? mu, clear; spores hyaline, muriform, -1/ascus, I+ blue?, ca. 100-220 x 15-40 mu, ca. ? x ? celled (densely muriform); chemistry: hypoprotocetraric and 4-O-demethylnotatic acids. NOTE: Description after Hale (1978). Not yet known from Costa Rica, but reported from Panama (Hale 1978).
in prep.

Thelotrema pachysporum Nyl. [Thelotrema lacteum Kremp.] - Thallus pale tannish or whitish grey, ca. 3 cm diam., endophloeodal or partly epiphloeodal, continuous, surface slightly shiny, with indistinct cortex, not oily; medulla indistinct; ascocarps immersed in slightly to distinctly raised, 0.4-0.8 mm wide warts with 0.2-0.4 mm wide, round pore with erect margin of thallus colour, showing the grey disc, with free inner excipulum forming a low white rim around the disc; hymenium 150-180 mu, clear; spores grey, transversely septate, -8/ascus, I-negative?, ca. 45-80(-100) x 8-15 mu, ca. 12-16(-24) celled, with thick outer wall; chemistry: no substance. Specimens studied: Sipman 48392j, 41543, 51959, 51802.
[T. lacteum] [T. lacteum]
Costa Rica (Sipman 51959); picture length = 3.5 mm. Costa Rica (Sipman 51802); picture length = 3.5 mm.
[T. lacteum] [T. lacteum]
Costa Rica (Sipman 48392j); picture length = 3.5 mm. Costa Rica (Sipman 53333); picture length = 3.5 mm.

Thelotrema porinoides Mont. et v.d.Bosch apud Jungh. - Thallus ashy white, ca. 3 cm diam., thin and in part endophloeodal, continuous, surface slightly shiny, with indistinct cortex, not oily; medulla indistinct; ascocarps immersed in distinctly raised, ca. 0.7 mm wide warts with 0.2-0.4 mm wide, round pore with thallus-coloured margin, showing the free, strongly incurved inner excipulum ring, without carbonisation, without columella; hymenium ? mu, clear; spores hyaline, transversely septate, 4-8/ascus, I+ blue?, ca. 40-50(-100) x 10(-15) mu, ca. 12(-25) celled; chemistry: stictic, constictic acids. Specimen studied: Sipman 51838. NOTE: nr. 51838 lacks ascospores. Neotropical specimens seem to have smaller spores than SE Asian material, ca. 50 x 10 mu and ca. 12-celled versus ca. 100 x 15 mu and ca. 25-celled.
[T. porinoides]
The Philippines (Elmer 14927); picture length = 4 mm.

Thelotrema refertum (Hale) Hale - Thallus pale grey, over 5 cm diam., epiphloeodal, fissured, surface shiny, with indistinct cortex, not oily; medulla indistinct; ascocarps single, immersed in finally slightly raised, 0.5-0.7 mm wide warts with 0.1-0.3 mm wide pore filled by one or more partly free inner excipulum rings, without carbonisation or columella; hymenium 60-100 mu, clear; spores hyaline, transversely septate, 8/ascus, I+ brownviolet, 24-35 x 8-9 mu, 5-9 celled; chemistry: hypoprotocetraric and 4-O-demethylnotatic acids. NOTE: The material deviates from the description by Hale (1978) by its thallus lacking an olivaceous tinge and the ascocarps being always single and with larger pores. The spores are unusual by the I+ brown-violet colour reaction, large end cells and swellings at the septa.
[T. refertum] [T. refertum]
Costa Rica (Sipman 53241); picture length = 3.5 mm. Costa Rica (Sipman 53359a); picture length = 3.5 mm.

Thelotrema spondaicum (Nyl.) Hale - Thallus pale grey, ca. 3 cm diam., epiphloeodal, continuous, surface slightly shiny, with indistinct cortex, not oily; medulla indistinct; ascocarps sessile, round to elongate, ca. 0.6-0.8 x 0.8-1.2 mm, with incurved, thallus-coloured margin and rounded to elongate or stellate pore, without externally visible inner excipulum; hymenium ca. 200 mu, guttulate; spores pale grey, muriform, 2/ascus, I-negative?, ca. 100 x 35 mu, 20 x 8 celled, with thin septa; chemistry: virensic acid (acc. to Harris 1989). Specimens studied: Sipman 41588. NOTE: An unusual species perhaps identical with "Phaeographis lecanographa (Nyl.) Staiger" of Staiger 2002.
[T. spondaicum]
Costa Rica (Sipman 41588); picture length = 3.5 mm.

Thelotrema subtile Tuck. - CR ??? Thallus greenish grey, 3 cm diam., epiphloeodal, continuous, surface slightly shiny, with distinct, not filmy cortex, not oily; medulla indistinct; ascocarps immersed in strongly raised, 0.4-1.2 mm wide warts with round, 0.2-0.5 mm wide pore with thallus-coloured rim showing the strongly incurved, pale, free inner excipulum; hymenium 80 mu, clear; spores hyaline, transversely septate, -8/ascus, I+ pale blue, ca. 35 x 9 mu, ca. 7 celled, with thick outer wall; chemistry: no substance. Specimen studied: Sipman 48219.
[T. scyphuliferum]
Costa Rica (Sipman 48219); picture length = 3.5 mm.

Thelotrema turgidulum (Müll. Arg.) Hale (non Vain.) - Thallus whitish ashy grey, 5 cm diam., epiphloeodal, thin, continuous, surface shiny, with distinct, not filmy cortex, not oily; medulla indistinct; ascocarps immersed in raised, 0.5-0.9 mm wide warts with round, 0.2-0.3 mm wide pore with thallus-coloured rim showing the pale, free inner excipulum; hymenium ? mu, clear; spores hyaline, transversely septate, 4-8/ascus, I+ blue?, ca. 50-55 x 10 mu, ca. 10-12 celled; chemistry: no substance. NOTE: Description after Hale (1978). Not yet known from Costa Rica, but reported from Panama (Hale 1978).
in prep.

Acanthotrema, Ampliotrema, Chapsa, Gyrotrema, Fibrillithecis, Leptotrema, Leucodecton, Melanotrema, Myriotrema, Ocellularia, Ramonia?, Redingeria, Reimnitzia, Stegobolus, Thelotrema