Freshwater Ascomycetes - Species Monograph
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| Genus |
Species |
Author |
| Isthmosporella |
pulchra |
Shearer & J.L. Crane |
| Class |
Order |
Family |
| Dothideomycetes |
Pleosporales |
Phaeosphaeriaceae |
MycoBank ID:
450566
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| Synonymy: |
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Description
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| Habit: |
Saprobic on submerged, decorticated wood. |
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| Ascomata: |
Ascomata scattered on decorticated wood, immersed obliquely, becoming erumpent to superficial, globose, black, membranous, glabrous, rostrate 310-330 x 225-240. |
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| Peridium: |
Ascomal wall 2-layered, inner layer composed of 5-7 rows of fusoid, subhyaline to light brown, compressed cells 11-20 x 2-3.5 µm; outer 3-4 cell layers composed of brown, pseudoparenchymatic, fusoid-cylindric cells 2-6.5 µm long. |
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| Beak: |
Beak short, cylindrical, periphysate, 60 µm long, 55 µm wide. |
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| Hamathecium: |
Hamathecium sparse, of broad, septate, interascal pseudoparaphyses. |
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| Ascus: |
Asci in a broad basal layer, fissitunicate, ventricose to clavate, broadly rounded at apex, short-stalked, 8-spored, persistent, (95-) 135-160 (-175) x (25-) 30-45 (-60) µm. |
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| Ascospore: |
Ascospores tri- to tetraseriate, hyaline, filled with lipid droplets that merge to form large guttules, cylindrical to fusoid, isthmoid at center, sometimes bent at isthmus and becoming u- or v-shaped, end cells tapering, 12-17-phragmoseptate, constricted at septa, 80-105 (-110) x (-7) 8-10 µm; isthmus 1-septate, 2-5.5 x 2.0-4.5 µm, frequently fragmenting to form part spores, surrounded by a gelatinous sheath. |
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| Sheath: |
Sheath gelatinous, as a thin layer at first; enlarging to a globose shape. |
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| Appendage: |
None observed. |
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| Culture: |
Colonies on yeast soluble starch agar (YPSS) containing balsa wood sticks effuse, white. Hyphae hyaline, septate. |
| Anamorph: |
Anamorph not observed. |
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Other info
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| Type & Location: |
USA. NEW YORK: Adirondack Park, Piercefield. Tupper Lake at public boat launch from Rt. 30, UTM Zone 18, 539840mE, 4892100mN; 44 10 59 N, 80 31 6 W, on submerged, decorticated wood, 7 Jul 1994, J.L. Crane & C.A. Shearer A-254-1, ILLS 53086. |
| Other Specimens: |
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| Substratum: |
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| Habitat: |
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| Distribution: |
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| Pertinent Literature: |
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| Comments: |
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Additional Pictures
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Ascospore
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Ascospore
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Ascus
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Ascus
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Sheath outlined in India ink
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Sheath showing dense region near midseptum
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