Hypoxylon anthochroum Berk. & Broome

TELEOMORPH | CULTURES AND ANAMORPH | SPECIMENS EXAMINED | NOTES

NOTES

Hypoxylon anthochroum was considered to be a synonym of H. rubiginosum by Miller (1961), as were H. albostigmatosum, H. guarapiense, and H. murcidum which are considered to be synonyms of H. anthochroum in this study. Hypoxylon anthochroum has dull reddish brown or blackish granules containing greenish or olivaceous KOH-extractable pigments as mentioned in Petch (1924), whereas H. rubiginosum has yellowish brown or brown granules containing orange KOH-extractable pigments.

Hypoxylon anthochroum shares most teleomorphic as well as anamorphic characteristics with H. placentiforme. The main differences lie in the latter taxon having massive basal tissue, long tubular perithecia, and a larger ascospore size range. The anamorph of H. subrutilum is very similar to that of H. anthochroum. Their teleomorphs are primarily separable by their ascospore size range and by the conspicuousness of the perispore ornamentation. Hypoxylon duranii and H. anthochroum have similar ascospore size ranges, but the conspicuousness of the coil-like perispore ornamentation and the conidium size range are useful for separating these two taxa. Also see H. fuscum for comparison.

In the protologue of H. anthochroum, two specimens of Thwaite, nos. 160 and 269, were cited. Miller (1961) cited only no. 160 as the type which is accordingly accepted as the lectotype of H. anthochroum. Shear (1945) reported that the type specimen of H. albostigmatosum was lacking at Spegazzini's herbarium of LPS. He then selected Balansa no. 2781 as a "substitute type" [lectotype].

A collection from Taiwan [Ping-tung Co., Heng-chun, Ken-ting, 11.9.1991, Ju, Y.-M. 80091101 (CULTURED), decorticated wood (JDR; NTU)] generally agrees with H. anthochroum in both the teleomorph and anamorph, except for having smaller perithecia, 0.1-0.2 mm diam x 0.4 mm high, having slightly larger ascospores, 12-14 (-15) x 6-7 mm, having longer ascal stipes, 115-135 mm long, and having smoke gray (105) sporulating regions on colonies. Another collection from Taiwan [Ping-tung Co., Heng-chun, Kong-ko, 24.8.1988, Ju, Y.-M. 77082404 (CULTURED), dead wood (JDR; NTU)] highly resembles H. anthochroum in the teleomorph except for having smaller perithecia, 0.1-0.2 mm diam x 0.3-0.4 mm high. Despite the fact that the colonies are much like those of H. anthochroum, the conidiogenous structure is Periconiella-like. These two collections are probably distinct from H. anthochroum, but are tentatively referred to it until more collections are studied.