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Rinodina spp.
Family: Physciaceae
Rinodina image
Stephen Sharnoff  
Life habit: lichenized or rarely lichenicolous, evanescent Thallus: crustose, or subumbilicate; areoles or verrucae: discrete at first, becoming contiguous; or thallus: continuous, becoming rimose or rimose-areolate surface: plane to rugose, light to dark gray, or ochraceous, gray-brown to brown; margin: determinate or indeterminate; prothallus: rarely present, lightly or darkly pigmented, entire or fimbriate; vegetative propagules: sometimes present as soredia, consoredia, blastidia, or isidia Ascomata: apothecial, innate, more usually adnate or sessile, usually frequent, except when vegetative propagules present disc: brown to black, rarely pruinose, rarely concave, plane to convex margin: lecideine in R. insularis only, otherwise lecanorine, concolorous with thallus, sometimes partially developed or absent, rarely biatorine or becoming biatorine, or becoming pigmented, entire, rarely crenulate or flexuose, persistent or becoming excluded; excipular ring: sometimes present, raised or confluent thalline exciple: typically with a narrow, cellular cortex laterally, sessile apothecia usually with a wider cortex below, cellular or comprised of intricate or columnar hyphae; epinecral layer: sometimes present laterally; cortical cells: pigmented or not photobiont: primary one a Trebouxia species, secondary one absent; cells: spherical or elongate by compression of radiating medullary hyphae proper exciple: hyaline or rarely pigmented brown, sometimes continuous below hypothecium, widening at periphery hymenium: sometimes inspersed; paraphyses: free or more rarely conglutinate, mostly unbranched except in epihymenium, with apical cells mostly swollen, usually with a darkly pigmented cap forming a brown epihymenium, or sometimes immersed in dispersed pigment to form a red-brown or rarely a blue-gray epihymenium; hypothecium: hyaline, rarely lightly or darkly pigmented, sometimes inspersed with oil drops asci: clavate, Lecanora-type (except Bacidia-type in R. insularis), 4-8 spored ascospores: brown, 1-septate, or 3septate to pseudomuriform in R. intermedia only, ellipsoid, type A or B development (Fig. 62), various types ( Fig. 63), sometimes constricted at septum at maturity; torus: present or absent; walls: ornamented or not Conidiomata: pycnidial: mostly immersed; conidiophores: types I, II, V or VI; conidia: bacilliform Secondary metabolites: not detected, or atranorin in cortex, and combinations of triter-penes, anthraquinones and xanthones, aliphatic acids, depsides, and depsidones present in the medulla Geography: world-wide Substrate: on calcareous or acidic rocks, corticolous on deciduous and coniferous species but rarely substrate specific, frequently on twigs and small branches, or over mosses in boreal or arctic-alpine habitats. Notes: Spore size and structure are very important characters in distinguishing among Rinodina species. Internal spore structure is often obscured by oil drops in freshly collected material. Spores are best observed by mounting apothecial sections in Lugol's Iodine solution and freeing them from their asci by applying pressure to the cover slip. This solution clears the spores without changing their dimensions. Separate sections should be prepared and mounted in K to observe the presence or absence of wall swelling in the septal region of spores. Spore dimensions are quoted as a range, within which the mean can be expected to fall with 95% confidence, the outer figures in brackets represent the range, in that 95% of the population is expected to occur. These measurements differ from those quoted in Sheard and Mayrhofer (2002) by being rounded outwards to the nearest 0.5 ┬Ám. It is necessary to measure 10 to 20 mature spores, recognized by the full development of wall pigmentation, in order to estimate the mean size. Overmature spores are characterized by wrinkled or buckled walls and loss of internal structure, and should not be measured. Observations of spore structure are also made on mature spores when septal and apical wall thickening define the shape of the internal lumina and their canals, on which the classification of spore types below is largely based. Spore development is also important: type A spores have apical wall thickenings developing after septum formation, while type B spores have apical wall thickening developing prior to septum formation (Fig. x1). The latter may be a very transient stage and difficult to observe in some species. The presence or absence of a torus is a variable feature within spore types, but it is a useful character at the species level. Observation of torus and wall ornamentation must be made under an oil immersion objective. Beltraminia-type: lacks internal wall thickenings; R. athallina. Bicincta-type: pigmented band present around each cell but may be very faint in some species and is absent in R. zwackhiana; septal and apical wall thickenings; often swollen around septum when immature; separate wall layers visible at septum, and sometimes apex, at maturity; R. castanomela, R. constrictula, R. luridata, R. zwackhiana. Bischoffii-type: pigmented band around septum; septal wall thickening; separate wall layers visible at septum; R. bischoffii, R. guzzinii. Dirinaria-type: type B development usually present; often swollen around septum at some stage of development, more so in K; septal and apical wall thickenings; separate wall layers may be visible at septum; R. californiensis, R. endospora, R. gennarii, R. insularis, R. marysvillensis, R. metaboliza, R. oregana, R. santae-monicae. Milvina-type: septal and apical wall thickenings but lumina less sharply angular than Physcia-type; typically broadly ellipsoid and waisted at maturity; R. milvina, R. rinodinoides. Mischoblastia-type: septal and apical wall thickenings very pronounced, lumina becoming triangular, walls usually lightly pigmented; R. oxydata. Pachysporaria-type: walls laterally and apically thickened, lumina becoming rounded, walls often lightly pigmented; R. coloradiana, R. griseosoralifera, R. isidioides, R. perreagens, R. poeltiana, R. roboris, R. verruciformis. Physcia-type: septal and apical wall thickenings forming sharply angular lumina; R. aurantiaca, R. badiexcipula, R. boulderensis, R. capensis, R. confragosa, R. glauca, R. hallii, R. innata, R. juniperina, R. laevigata, R. mniaraea. Physconia-type: septal wall thickening similar to Physciatype but apical thickening lost at maturity; R. grandilocularis, R. archaea, R. pacifica, R. pyrina, R. trevisanii. Submuriform-type: 1-3-septate when immature, to more than four lumina at maturity, with thick walls; R. inter-media. Teichophila-type: septal and apical wall thickening to form lumina of variable shape, Mischoblastia-, to Physcia-, to Pachysporaria-type during development; sep