Zhang, B.C.; Minter, D.W. 1988: Two new species of Labyrinthomyces from New Zealand, with notes on the taxonomy of the genus. Systema Ascomycetum 7(1): 45-55.
![Figs 1-5. Labyrinthomyces phymatodeus (holotype). Fig. 1. View of ascoma in section, showing the labyrinthine fertile chambers remaining full(bar = 5 mm). Fig. 2. Peridial structure (bar = 200 µm). Fig. 3. Fertile chamber lined with hymenium (bar = 200 µm).Figs 4-5. Light micrographs of ascospores, showing optical section (Fig. 4) and surfaceornamentation (Fig. 5) (bar = 10 µm). © All rights reserved. [Image: A67]](https://data.landcareresearch.co.nz/Image/A67/SysPortalThumb)
![Figs 6-10. Labyrinthomyces turbinatus (holotype). Fig. 6. Ascoma (bar = 10 mm).Fig. 7. View of ascoma in section, showing the labyrinthine fertile chambers remaining full(the dark holes are areas eaten by insects) (bar = 5 mm). Fig. 8. Peridial structure (bar = 200 µm).Fig. 9. Fertile chamber lined with hymenium (bar = 200 µm). Fig. 10. Light micrograph of ascospores in optical section (bar = 10 µm). © All rights reserved. [Image: A68]](https://data.landcareresearch.co.nz/Image/A68/SysPortalThumb)
![Figs 11-14. Scanning electron micrographs of ascospores of Labyrinthomyces species (bar =10 µm). Fig. 11. Labyrinthomyces phymatodeus (holotype). Figs 12-14. Labyrinthomyces turbinatus (holotype).Fig. 12. Ascospores covered with ascus walls. Fig. 13. Young ascospore with early stages of ornamentation.Fig. 14. Older ornamented ascospore. © All rights reserved. [Image: A66]](https://data.landcareresearch.co.nz/Image/A66/SysPortalThumb)
![Figs 1-5. Labyrinthomyces phymatodeus (holotype). Fig. 1. View of ascoma in section, showing the labyrinthine fertile chambers remaining full(bar = 5 mm). Fig. 2. Peridial structure (bar = 200 µm). Fig. 3. Fertile chamber lined with hymenium (bar = 200 µm).Figs 4-5. Light micrographs of ascospores, showing optical section (Fig. 4) and surfaceornamentation (Fig. 5) (bar = 10 µm). © All rights reserved. [Image: A67]](https://data.landcareresearch.co.nz/Image/A67/SysPortalPreview)
![Figs 6-10. Labyrinthomyces turbinatus (holotype). Fig. 6. Ascoma (bar = 10 mm).Fig. 7. View of ascoma in section, showing the labyrinthine fertile chambers remaining full(the dark holes are areas eaten by insects) (bar = 5 mm). Fig. 8. Peridial structure (bar = 200 µm).Fig. 9. Fertile chamber lined with hymenium (bar = 200 µm). Fig. 10. Light micrograph of ascospores in optical section (bar = 10 µm). © All rights reserved. [Image: A68]](https://data.landcareresearch.co.nz/Image/A68/SysPortalPreview)
![Figs 11-14. Scanning electron micrographs of ascospores of Labyrinthomyces species (bar =10 µm). Fig. 11. Labyrinthomyces phymatodeus (holotype). Figs 12-14. Labyrinthomyces turbinatus (holotype).Fig. 12. Ascospores covered with ascus walls. Fig. 13. Young ascospore with early stages of ornamentation.Fig. 14. Older ornamented ascospore. © All rights reserved. [Image: A66]](https://data.landcareresearch.co.nz/Image/A66/SysPortalPreview)
Details
Details
Descriptions
Peridium 500-1000(-1300) µm thick, including warts 300-450 µm high, with two distinct layers. Outer layer 200-300 µm thick, pale brown, composed of brown pigmented cells up to 24 µm diam, forming a textura angularis. Inner layer 300-700(-1000) µm thick, including the inner part of the warts, pale yellowish brown, composed of hyphae up to 5 µm diam, forming a very loosely interwoven textura intricata, often giving rise to empty irregular locules.
Gleba yellowish brown, with paler sterile veins composed of pale brown hyphae up to 8 µm diam forming a loose textura intricata, separating the fertile chambers. Fertile chambers numerous, lined with hymenium, completely filled with ascospores and the remnants of asci. Paraphyses cylindrical, nearly colourless, slender, the same length as asci, hard to observe.
Asci cylindrical, about 200 x 35 µm, thin-walled, fragile, with only the remnants of their walls visible in older ascomata, mostly 8-spored, not turning blue in Melzer's reagent, with a cyanophilic wall.
Ascospores uniseriate within the asci, globose, pale brown, 17.5-22 µm diam excluding ornamentation, with walls up to 1.5 µm thick, coarsely ornamented with strongly cyanophilic, hemispherical and sometimes confluent warts up to 3 µm high and 4 µm diam at the base.
Labyrinthomyces phymatodeus differs from all other species in the subgenus in having ascomata with conspicuous warts on which parallel lines are present, and in having ascospores ornamented often with larger hemispherical warts. It also differs from L. varius and Labyrinthomyces sp. (PDD 48338) in having its glebal fertile chambers remaining filled with ascospores; from L. turbinatus in having dark brown ascomata which are not turbinate, but which have a thicker and differently structured peridium; and from L. tesselatus in having larger ascomata again with a thicker and differently structured peridium.
The dark brown, warty ascomata, the glebal structure and the distribution of L. phymatodeus made it so similar to the description of the monotypic genus, Dingleya Trappe (Trappe, 1979), that the specimen was found filed under the name "Dingleya sp." in K. Examination of type material, however, showed that ascospores of D. verrucosa Trappe (PDD) are ellipsoid, with an amorphous, ridged ornamentation. Labyrinthomyces phymatodeus is thus sufficiently different in ascospore morphology that it cannot be placed in Dingleya. The globose ascospores ornamented with hemispherical warts and glebal structure of L. phymatodeus do, however, agree well with the circumscription of Labyrinthomyces.
Labyrinthomyces turbinatus differs from L. tesselatus in having larger, pale brown, often turbinate ascomata, often with flattened polygonal warts, and in having ascospores ornamented with sparse, irregular, smaller warts (figs 10, 14-15). It differs from L. varius in having ascomata which are not tomentose, glebal fertile chambers remaining filled with paraphyses, asci and ascospores, paraphyses equalling the length of asci, and much thinner ascus walls.
The collection of Labyrinthomyces sp. from New Zealand (PDD 48338) comprised a single ascoma. We consider this does not provide enough information to resolve its taxonomic status. Based on Dr. Beaver's [sic] unpublished descriptions and our examination of the specimen, a short description follows.
Ascomata globose, about 20 mm diam, dark brown, surface covered with poorly defined, minute warts (up to 500 µm in the largest dimension at the base). Peridium 1-1.5 mm thick, of two distinct layers. Gleba yellowish white to brown, composed of elongated, straight, sinuous or rounded, labyrinthine chambers lined with hymenium but. becoming empty. Paraphyses about 150 x 3 µm. Asci not seen. Ascospores globose, (18-)19-21(-22) µm diam excluding ornamentation, with walls about 1 µm thick, often containing one large droplet or two smaller ones, smooth when young, later becoming irregularly ornamented with hemispherical warts up to 3.5 µm diam.
In both gross and microscopic morphology this collection seems rather similar to L. varius, especially in glebal structure and ascospores. Its uneven ascomatal exterior is, however, somewhat different from L. varius. We cannot confidently recognise this fungus as a distinct taxon on the basis of this single collection. Information about the asci and paraphyses would be needed from further collections to resolve its taxonomic status. It seems probable, however, that like the other two species described earlier, it belongs in the subgenus Labyrinthomyces.
Peridium 400-650 µm thick (including warts 80-250 µm high), with two distinct layers and a very variable structure. Outer layer ca 100 µm thick, pale brown, composed of hyphae to 13 µm diam with walls up to 2 µm thick, forming a textura angularis to epidermoidea, both types of structure sometimes being visible in the same section. Inner layer 300-550 µm thick, not clearly distinct from the gleba, slightly pigmented or nearly colourless when close to the gleba, usually composed of hyphae up to 16 µm diam, forming a textura angularis, often also with thinner hyphae about 8 µm diam, mixed with a few thicker (up to 12 µm diam), more pigmented, straight, septate hyphae with walls about 1.5 µm thick, forming a textura intricata.
Gleba pale yellowish-brown, solid with paler labyrinthine veins separating individual closed fertile chambers completely filled with asci and hyphae and lined with hymenium. Hyphae in the veins 4-6 µm diam, colourless, septate, forming a textura intricata, but, sometimes up to 16 µm diam and forming a textura globulosa. Paraphyses cylindrical, colourless, about 5 µm diam, with rounded, free, slightly swollen tips, the same length as the asci or often elongated and anastomosing with the paraphyses arising from the opposite side of the fertile chamber.
Asci cylindrical, tapering towards the base, 250-300 x ca 35 µm, with walls up to 1.5 µm thick, not turning blue in Melzer's reagent, 8-spored, often with 1-2 spores aborted.
Ascospores uniseriate within asci, globose, 18-25 µm diam excluding ornamentation, with walls up to 3 µm thick, often with one droplet in each ascospore; young ascospores smooth, colourless, becoming pigmented and ornamented with strongly cyanophilic warts when older; at first slightly pigmented with minute warts about 1 µm high and 1 µm diam at the base, later pale brown, with sparse hemispherical warts up to 1.5 µm high and 2 µm diam at the base.
Etymology: turbinatus (Latin, "turbinate") describing the ascomaaal shape.
Notes on New Zealand Labyrinthomyces species
Labyrinthomyces phymatodeus differs from all other species in the subgenus in having ascomata with conspicuous warts on which parallel lines are present, and in having ascospores ornamented often with larger hemispherical warts. It also differs from L. varius and Labyrinthomyces sp. (PDD 48338) in having its glebal fertile chambers remaining filled with ascospores; from L. turbinatus in having dark brown ascomata which are not turbinate, but which have a thicker and differently structured peridium; and from L. tesselatus in having larger ascomata again with a thicker and differently structured peridium.
The dark brown, warty ascomata, the glebal structure and the distribution of L. phymatodeus made it so similar to the description of the monotypic genus, Dingleya Trappe (Trappe, 1979), that the specimen was found filed under the name "Dingleya sp." in K. Examination of type material, however, showed that ascospores of D. verrucosa Trappe (PDD) are ellipsoid, with an amorphous, ridged ornamentation. Labyrinthomyces phymatodeus is thus sufficiently different in ascospore morphology that it cannot be placed in Dingleya. The globose ascospores ornamented with hemispherical warts and glebal structure of L. phymatodeus do, however, agree well with the circumscription of Labyrinthomyces.
Labyrinthomyces turbinatus differs from L. tesselatus in having larger, pale brown, often turbinate ascomata, often with flattened polygonal warts, and in having ascospores ornamented with sparse, irregular, smaller warts (figs 10, 14-15). It differs from L. varius in having ascomata which are not tomentose, glebal fertile chambers remaining filled with paraphyses, asci and ascospores, paraphyses equalling the length of asci, and much thinner ascus walls.
