Freshwater Ascomycetes - Species Monograph
Click on the pictures below to view them at their full size.
| Genus |
Species |
Author |
| Pseudohalonectria |
phialidica |
C.A. Shearer |
| Class |
Order |
Family |
| Sordariomycetes |
Inc. sed. |
Magnaporthaceae |
|
| Synonymy: |
|
Description
|
| Habit: |
Saprobic, ascomata immersed or partially immersed in submerged, dead woody debris. |
|
| Ascomata: |
Ascomata 129-366 x 257-426 µm, on wood solitary to somewhat aggregated, immersed, partially immersed, or superficial; venter flattened globose, yellow becoming greyish yellow. |
|
| Peridium: |
Peridium membranous, of textura angularis in surface view, brownish yellow, inner layer of laterally compressed hyphae, yellow, paler towards venter cavity, cells of outer layer less compressed and surrounded on the outside by loosely interwoven hyphae bearing orange-brown amorphous material. |
|
| Beak: |
Beaks 614-1946 x 89-129 µm, beaks cylindrical, long, periphysate, wall comprising an inner layer of parallel hyphae with elongated cells, middle layer of outwardly divergent hyphae, and an outer layer of loosely interwoven hyphae on which orange-brown amorphous material is deposited. |
|
| Hamathecium: |
Paraphyses 132-168 µm long, 4.8-9.6 µm wide at base, longer than asci, broad at base and tapering to a gently rounded point, attached to ascogenous hyphae. |
|
| Ascus: |
Asci 82-99 x 5-7.9 µm, pale yellow, cylindrical, straight or sigmoid, with IKI-negative thimble shaped apical apparatus, 3.2-5 x 2-3.5 µm, that stains bright blue in slightly acidic aqueous cotton blue; detaching from ascogenous hyphae at the basal septum and lying free in venter cavity. |
|
| Ascospore: |
Ascospores 64.5-79 x 2 µm, hyaline, yellow becoming orange in mass, filiform, slightly curved or sigmoid, 0 to 4 septate, with oil droplets interrupted at regular intervals by nonrefractile regions. |
|
| Sheath: |
None observed. |
|
| Appendage: |
None observed. |
|
| Culture: |
ATCC. Colonies on cornmeal agar floccose, appressed, cream colored, becoming tinged with grey, colony reverse yellow. Hyphae septate, smooth walled, branched, hyaline to pale yellow, 1-3.5 µm in diameter. |
| Anamorph: |
Hyphomycetous, phialidic. Phialides hyaline, micronematous, flask shaped, 9.9-26.7 x 2-4 µm, collarette 2-3 µm wide. . Conidia allantoid, hyaline, nonseptate, 2-4 x 0.5-1 µm. |
|
Other info
|
| Type & Location: |
USA. Illinois: Vermilion County, Salt Fork of the Vermilion River, A dried culture grown on balsa wood, derived from a single ascospore from an ascoma on submerged woody debris, C. A. Shearer, CS-719-1, Apr 1983. NY |
| Other Specimens: |
|
| Substratum: |
Wood |
| Habitat: |
Lotic |
| Distribution: |
USA (IL) |
| Pertinent Literature: |
Shearer, C.A. 1989. Pseudohalonectria (Lasiosphaeriaceae), an antagonistic genus from wood in freshwater. Canadian Journal of Botany 67: 1944-1955. |
| Comments: |
|
Additional Pictures
|
Ascospore 1
|
|
|
Back
|
|
