Biology:Xenonectriella nephromatis
| Xenonectriella nephromatis | |
|---|---|
Scientific classification 
| |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Sordariomycetes |
| Order: | Hypocreales |
| Family: | Nectriaceae |
| Genus: | Xenonectriella |
| Species: | X. nephromatis
|
| Binomial name | |
| Xenonectriella nephromatis Pérez-Ort. (2020)
| |
Xenonectriella nephromatis is a little-known species of lichenicolous (lichen-dwelling) fungus in the family Nectriaceae.[1] Found in Alaska, it was described as a species new to science in 2020 by Sergio Pérez-Ortega. The type specimen was discovered in the Hoonah–Angoon Census Area in Glacier Bay National Park and Preserve, where it was growing on a Nephroma lichen. The specific epithet alludes to this host lichen.[2]
Description
Xenonectriella nephromatis produces minute, flask-shaped fruiting bodies (ascomata) that develop inside the tissue of its lichen host. At first they are completely embedded, but as they mature they burst through the surface ([[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]]) and appear as scattered, dark-red dots up to 0.6 mm wide. Each ascoma is nearly spherical to pear-shaped and lacks the external hairs sometimes seen in related fungi. Its wall is several cells thick: the outer layers consist of enlarged, brick-like cells that give the structure a reddish-orange hue, while the innermost layers are made of flattened, colorless cells. A simple spot test with potassium hydroxide (KOH) solution turns the wall a vivid violet-purple, a reaction that helps distinguish the species in the field. Around the tiny pore (ostiole) at the top, numerous slender filaments ([[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]]) 15–25 μm long form a low cone that guides the spores outward.[2]
Inside the spore chamber, the clear spore-bearing layer (hymenium) is packed with long, thin, eight-spored sacs (asci) that measure about 120–130 × 8–12 μm. The asci have a single flexible wall ([[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]]), broaden slightly at the tip, and open by a small slit rather than a lid. Their contents are arranged in a single file ([[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]]) and consist of broadly ellipsoid spores that vary somewhat in outline but are always divided by one cross-wall (1-septate). The ascospores are transparent, only faintly pinched at the septum, have rounded ends, and display a delicate surface pattern; they measure 12–16 × 5–8 μm. No sterile filaments between the asci (paraphyses) have been seen in mature material, and asexual reproductive structures are unknown for this species.[2]
References
- ↑ "Xenonectriella nephromatis Pérez-Ort.". Species 2000: Leiden, the Netherlands. https://www.catalogueoflife.org/data/taxon/B37QX.
- ↑ 2.0 2.1 2.2 Spribille, Toby; Fryday, Alan M.; Pérez-Ortega, Sergio; Svensson, Måns; Tønsberg, Tor; Ekman, Stefan; Holien, Håkon; Resl, Philipp et al. (2020). "Lichens and associated fungi from Glacier Bay National Park, Alaska". The Lichenologist 52 (2): 61–181. doi:10.1017/S0024282920000079. PMID 32788812.
Wikidata ☰ Q108479553 entry
 |  |
