Pachyphysis ozarkana R.C.Harris & Ladd
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Family
Lecideaceae (Ascomycota)
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Scientific Name
Pachyphysis ozarkana R.C.Harris & Ladd
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Description
Type: - MISSOURI. BARRY CO.: Roaring River State Park, Roaring River Hills Wild Area along state highway F, 36°34'50"N, 93°50'00"W, dolomite glade with Juniperus, 3.xi.2000, Harris 44707 (NY, holotype).
Description: (From Harris & Ladd 2007) - Thallus endolithic, not visible when on fine-grained dolomite/limestone (Ozarks), or traces of whitish epilithic thallus when on more pervious sandstone (Wisconsin); no substances detected by TLC. Photobiont chlorococcoid, not abundant, in a +/- discontinuous layer; cells globose, 7-13 µm. Apothecia black, 0.5-1.2 mm across, usually with patches of diffuse white pruina, sessile (or in some Kansas specimens +/- immersed, forming shallow pits in limestone), slightly to strongly constricted at the base, initially +/- flat becoming swollen and hemispherical, initially with thick, slightly raised margin which is usually excluded with age; apothecial initials in pits in dolomite. Exciple of radiating hyphae with large lumina embedded in well developed gelatinous matrix, +/- colorless streaked with purple or with purple-black pigment masses or entirely purple, K+ red-purple; inner part often continuous with hypothecium and sometimes scarcely distinguishable from hypothecium. Hypothecium very gelatinous, dark brown to blackish purple, purple coloration more intense in K, red in HNO3. Epihymenium grayish to olive or greenish (K-, N+ red) with numerous small colorless crystals on surface. Hymenium brownish (K- or K+ weakly purplish, N+ red-orange) in upper part, shading into and sometimes obscured by red-purple pigment (K+ intensely red-purple, N+ purple) in lower part (subhymenium?). Paraphyses of two kinds, some clavate, to ca. 10 µm thick (including thick gelatinous sheath); lumen toward base ca. 2 µm across, at top to ca. 7 µm across, others not or little expanded at tips with lumen 3-4 µm across, both types branched and anastomosed, sometimes so gelatinized as to be indistinguishable. Ascus Porpidia-type, +/- clavate, with eight, irregularly arranged spores. Ascospores broadly ellipsoid to globose, not halonate, 10-13 x 8-10 µm or 10-12 µm across. Pycnidia with blue-green wall, ca. 0.1 mm diameter, mostly immersed. Conidia +/- bacilliform although sometimes tapered at one or both ends, 6-8 x 1-1.5 µm.
Etymology: (From Harris & Ladd 2007) - Pachyphysis from pachys = thick and -physis from paraphysis, in reference to the distinctive thick paraphyses, ozarkana from region of the taxon's discovery and source of the majority of known collections.
Distribution and ecology: (From Harris & Ladd 2007) - Frequent on exposed limestone and dolomite throughout the range of these substrates in the Ozarks, growing on both small pebbles and cobbles and on massive outcrops and boulders, usually on horizontal surfaces. The most typical habitat for this species in the Ozarks is dolomite glade. This species is known from carbonate bedrock regions of the Interior Low Plateau of Kentucky and Tennessee, westward through the Ozarks and into the Tallgrass and mixed grass regions of the central Great Plains of Kansas and Oklahoma, southwest into Texas. It is also known from the driftless area of southwestern Wisconsin, where it occurs on calcareous sandstone. It is interesting that all known sites for this species are in landscapes that remained unglaciated during the last glacial interval.
Discussion: (From Harris & Ladd 2007) - Pachyphysis is distinctive in the very thick paraphyses and the often globose ascospores. We have been unable to assign Pachyphysis ozarkana to any known genus of Porpidiaceae or match it with any known species of Lecidea s. lat. The ascus after KI treatment shows a definite dark staining 'tube' in the tholus (sometimes seen as a stack of rings), which seems to fit the Porpidia type ascus. It is primarily on this basis that Pachyphysis is assigned to the Porpidiaceae s. lat. Buschbom (2004) found that Pachyphysis was not included within a narrow Lecideaceae/Porpidiaceae clade but was in a clade with Farnoldia and Melanolecia, differing from them in paraphyses and apothecial pigmentation. This is interesting as both are strong calciphiles. One collection (Buck 32057) hosts a lichenicolous fungus tentatively identified as Muellerella pygmaea (Körber) D. Hawksw. var. athallina (Müll. Arg.) Triebel. Unfortunately this taxon has a wide host range and is not informative as to the familial position of the host. In the field Pachyphysis ozarkana closely resembles Lecidella stigmatea (Ach.) Hertel & Leuckert but can be distinguished by the large apothecia with patchy white pruina. It can also be mistaken for less pruinose forms of Sarcogyne regularis Körber which lacks the highly colored tissues of Pachyphysis and has polysporous asci. Species of Clauzadea are rare in the Ozarks and lack pruina on the apothecia as well as lacking a grayish to olive or greenish epihymenium. Despite the paucity of lichen work in middle portions of North America, Pachyphysis is sufficiently common and widely distributed that it must have been collected earlier but it remains something of a puzzle as to what it might have been named. Alan Fryday in his review suggested misidentified specimens of Lecidea phylliscina Nyl. (= Porpidia macrocarpa (DC.) Hertel & Knoph) as a possibility to be investigated.
- Sorry, no descriptions available for this record.