Magnaporthales » Pseudohalonectriaceae

Pseudohalonectria

Pseudohalonectria Minoura & T. Muroi

 

Asexual morph: Hyphomycetous, phialidic. Phialides hyaline, micronematous, flask-shaped. Conidia allantoid, hyaline, aseptate. Sexual morph: Ascomata immersed or partially immersed, with a long neck, globose to subglobose. Peridium membranous. Paraphyses numerous, septate, hyaline. Asci unitunicate, cylindrical, straight or curved, with J-, thimble-shaped apical ring. Ascospores overlapping uniseriate to biseriate, multi-seriate, filiformes, septate.

Type species: Pseudohalonectria lignicola Minoura & T. Muroi, Trans. Mycol. Soc. Japan 19(2): 132 (1978)

Notes: The genus Pseudohalonectria was introduced to accommodate P. lignicola (Minoura & Muroi 1978). Hongsanan et al. (2017) introduced Pseudohalonectriaceae as a new family within Magnaporthales to accommodate Pseudohalonectria. Sixteen species are accepted in this genus, of which six species have been reported from freshwater habitats worldwide (Minoura and Muroi 1978; Shearer 1989a, b; Hyde et al. 1998; Cai et al. 2002).

 

References

Cai L, Tsui CKM, Zhang KQ, Hyde KD (2002) Aquatic fungi from Lake Fuxian, Yunnan, China. Fungal Divers 9:57–70.

Hongsanan S, Maharachchikumbura SSN, Hyde KD, Samarakoon MC et al. 2017 – An updated phylogeny of Sordariomycetes based on phylogenetic and molecular clock evidence. Fungal Diversity 84, 25–41.

Hyde KD, Goh TK (1998) Tropical Australian freshwater fungi XIII. A new species of Anthostomella and its sporodochial Geniculosporium anamorph. Nova Hedwig 67:225–233.

Minoura, K.; Muroi, T. 1978. Some freshwater ascomycetes from Japan. Transactions of the Mycological Society of Japan. 19:129-134.

Shearer CA (1989a) Pseudohalonectria (Lasiosphaeriaceae), an antagonistic genus from wood in freshwater. Can J Bot 67:1944–1955

Shearer CA (1989b) Aniptodera (Halosphaeriaceae) from wood in freshwater habitats. Mycologia 81:139–146

Tsui CKM, Hyde KD, Fukushima K (2001) Fungi on submerged wood in the Koito River, Japan. Mycoscience 44:55–59

 

Figs. 1-6. Pseudohalonectria lignicola. Fig. 1. Developing and mature asci and paraphyses. x410. Fig. 2. Attachment of asci and a paraphysis to ascogenous hyphae. X775. Fig. 3. Ascus mounted in water showing thimble-shaped ascus apparatus. x450. Fig. 4. Ascus fixed and stained in lactic acid with azure A and showing free basal end. x480. Fig. 5. Immature ascus with partially ruptured wall mounted in water and showing thimble-shaped ascus apparatus and frill of ascogenous hyphae attached to basal end. x633. Fig. 6. Ascospores mounted in water showing cells filled with lipid droplets. x595. Figs.7 and 8. P. adversaria. Fig. 7. Ascospores mounted in water showing cells filled with lipid droplets. x997. Fig. 8. Developing asci and paraphyses attached to ascogenous hyphal system. x550.

 

Fig. 9. Pseudohalonectria adversaria; Ascus showing thimble-shaped ascus apparatus and free basal end. x590. Figs.10-15. P. falcata; Fig. 10. Mature ascus mounted in water. x574. Fig. 11. Falcate ascospore mounted in water showing cells filled with lipid droplets. x608. Fig. 12. Ascus mounted in lactic acid with azure a showing flattened ascus apical apparatus. x737. Fig. 13. System of ascogenous hyphae and developing tortuous paraphyses. x440. Fig. 14. Paraphysis mounted in water showing the large, pseudoparenchymatic cells of which it is comprised. x827. Fig. 15. Asci and paraphyses attached to the system of ascogenous hyphae. x737. FIG. 16. P. longirostrum; Filiform and sigmoidal ascospores. x800.

 

Figs.17and 18. Pseudohalonectria longirostrum. Fig. 17. Asci mounted in lactic acid and azure a showing sigmoidal shape and the thimble-shaped apical apparatus. X780. Fig. 18. Thimble-shaped apical apparatus. x2960. Figs.19-22. P. lutea. Fig. 19. Ascospore mounted in lactic acid with azure A showing prominent septa. x1033. Fig. 20. Ascospore mounted in water showing cells filled with lipid droplets and different consistency of cell contents of the end cells. x944. Fig. 21. Ascus with free basal end. x 605. Fig. 22. Ascus apex with thimble-shaped ascus apparatus. x990. Figs.23-26. P. phialidica. Fig. 23. Ascus with free basal end. X878. Fig. 24. Asci and paraphyses attached to the system of ascogenous hyphae. x428. Fig. 25. Filiform ascospore with cells filled with lipid droplets and characteristic regions devoid of lipid droplets. x600. Fig. 26. Phialides with developing falcate conidia. x2000.

 

Fig. 27. Pseudohalonectria lignicola. Longitudinal section through the beak showing (A) the outer layer of outwardly directed hyphae of enlarged cells; (B) the inner layer of compressed, parallel hyphae of narrow, elongate cells; and (C) periphyses. x910. Fig.28. P. phialidica. Longitudinal section through the beak showing (A) the outer layer of loosely woven hyphae (arrow indicates orange, amorphous material deposited on the surface of ascomata); (B) the inner layer of parallel hyphae comprising narrow, elongate cells; and (C) periphyses. x950. Fig. 29. P. falcata. Longitudinal section through the venter showing (A) the outer layer of loosely woven hyphae; (B) the middle layer of pseudoparenchyma; and (C) the hymenium. x625. Fig. 30. P. lignicola. Longitudinal section through the venter showing (A) the outer layer of compressed pseudoparenchyma; (B) the middle layer of pseudoparenchyma; and (C) the hymenium. x780. Fig.31. P. phialidica. Longitudinal section through the venter showing (A) the outer layer of loosely woven hyphae; (B) the middle layer of pseudoparenchyma with slightly elongate and laterally compressed cells; and (C) the inner layer of tightly compressed pseudoparenchyma x935. Fig. 32. P. lignicola. Face view of peridium tissue. x1190.

 

Fig. 33. Pseudohalonectria species. (A-D) P. falcata. A, ascoma; B, ascospores; C, ascus; D, ascus apex. (E-H) P. lignicola. E, ascoma; F, ascus; G, ascus apex; H, ascospores. (I-L) P. adversaria. I, ascoma; J. ascus; K, ascus apex; L, ascospores. (M-Q) P. phialidica. M, ascoma; N, ascus; 0, ascospores; P, ascus apex; Q, phialidic state. (R-T) P. lutea. R, ascoma; S, ascospores; T, ascus. (U-X) P. longirostrum. U, ascoma; V, ascus; W, ascus apex; X, ascospores. Scale bars for all figures except A, E, I, M, R, and U = 10 µm; scale bars for A, E, I, M, R, and U = 100 µm.

 

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