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 Add this item to the list  814982 Original description
Remarks (public):Hypoxylon lilloi might be confused with H. vogesiacum due to their similar purplish gray or vinaceous grey stromatal surfaces. However, H. lilloi differs in having livid purple KOH-extractable pigments, smaller ascospores and in lacking a dotted band in the centre of the ascospores. This new taxon resembles the group of species with purplish KOH-extractable pigments, such as H. lienhwacheense, H. lividicolor, H. lividipigmentum and H. texcalense. Those can be easily differentiated from H. lilloi by the color of the stromatal surface and granules. In addition H. lienhwacheense has smaller ascospores (6-7.5 x 3-3.5 µm vs. 7.4-9.7 x 3.6-4.6 µm) and a smooth perispore. Hypoxylon lividicolor differs in having longer perithecia (0.5-1.3 x 0.2-0.4 mm vs. 0.5-0.8 x 0.2-0.3 mm), larger ascospores (11-12.5 x 4.5-5 vs. 7.4-9.7 x 3.6-4.6 µm) and sporothrix-like conidiogenous structures and H. lividipigmentum can be differentiated by its larger ascospores (10-15 x 4.5-6 µm vs. 8.5-10 x 4-4.5 µm) and nodulisporium-like conidiogenous structures. In comparison with H. texcalense the latter has also much larger ascospores (17-24 x 6.5-9.5 µm vs. 7.4-9.7 x 3.6-4.6 µm), absent apical rings and nodulisporium-like conidiogenous structures. The type of secondary metabolites produced in the stromata seems to be a unique feature of the species, because they were not detected in more than 1000 studied specimens. Only BNT could be identified, which is common in hypoxyloid genera of the Xylariaceae. In the phylogenetic reconstruction based on β-tubulin gene sequences (cf. Fig, 4) H. lilloi forms a separated clade. The latter is located between the H. fragiforme clade and H. lenormandii clade. Besides huge morphological differences of those species compared to H. lilloi, they can be easily distinguished by their orange KOH-extractable pigments due to the production of azaphilones-type natural products such as the mitorubrins (H. fragiforme, H. rickii, H. jecorinum, H. cinnabarinum) and the lenormandins (H. lenormandii, H. jaklitschii). 
Description type:Original description 
Description:Differs from Hypoxylon vogesiacum by livid purple stromatal pigments in 10% KOH, as well as in having an amyloid apical apparatus and smaller ascospores. Sexual morph: Stromata effused-pulvinate, 14-30 mm long x 5-26 mm broad x 1 mm thick; plane or with inconspicuous perithecial mounds; surface Purplish Gray (128) or Vinaceous Grey (116); pruinose; brown to dark red granules immediately beneath surface and between perithecia; with KOH-extractable pigments Livid Purple (81), the tissue below the perithecial layer inconspicuous, black, 0.2-0.5 mm thick. Perithecia obovoid to lanceolate-tubular 0.5-0.8 mm high x 0.2-0.3 mm diam; ostiolar openings lower than the stromatal surface, umbilicate with white area surrounding ostioles. Asci 8-spored, cylindrical, 92-134.5 µm total length, the spore-bearing parts 56-46 µm long x 5-6.5 µm broad, the stipes 40-82.5 µm long; with amyloid, discoid apical apparatus 0.7-0.9 µm high x 1.9-2.3 µm broad. Paraphyses 2-4 µm wide at base, tapering above asci. Ascospores brown to dark brown, unicellular, ellipsoid-inequilateral, with narrowly rounded ends, slightly curved, 7.4 - 8.9 (9.7) x 3.2 - 4.2 µm (N = 60, Me = 8.3 x 3.8 µm); with straight germ slit spore-length on convex side; perispore dehiscent in KOH; with inconspicuous coil-like ornamentation by light microscopy, revealing reticulate ornamentation by SEM (5000x); epispore smooth. Asexual morph in culture: Conidiophores with virgariella-like branching pattern, usually borne on aerial hyphae, hyaline, smooth. Conidiogenous cell hyaline, smooth, 10-27 x 1-2.5 μm. Conidia ellipsoid, hyaline, smooth, 4-5 x 1.5-2.5 μm. Culture: Colonies on OA covering Petri dish in 2 week, at first whitish, becoming Olivaceous Grey (121) to Dull Green (70), felty, zonate, with entire margin; reverse Apricot (42), later turning Dark Green (21) in places. Sporulating regions scattered over entire surface of colony. Secondary metabolites: Stromata of this species contain two unknown major metabolites in its stromatal extracts (Fig. 3) in addition to some other yet unknown minor metabolites, besides binaphthalene tetrol (BNT). 
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