Anthracoidea transberingiana M. Piątek, 2014

Piątek, Marcin, 2014, Anthracoidea transberingiana, a new smut species on Carex pauciflora from Beringia, Phytotaxa 174 (2), pp. 105-110 : 106

Anthracoidea transberingiana M. Piątek , sp. nov. ( Fig. 1 )

MycoBank # MB 809064

Type: — U.S.A. Alaska: Kenai Peninsula, below Lookout Mountain , NE of Homer , 59°43´N, 151°21´W, on Carex pauciflora , 23 Aug. 1951, J. A . Calder (holotype BPI 171459 !, isotype DAOM 28243 ) .

Sori in single ovaries of the inflorescences, forming black, globose or subglobose bodies around the achenes, about 1.5–1.8 mm in diameter, semi-hidden by the perigynium, exposed only from one side and enclosed by the other side of perigynium; sori composed of semi-agglutinated spores, powdery on the surface. Spores small-sized, flattened, reddish-brown, rather regular in shape and uniform in size, globose, subglobose, or sometimes weakly polyangular or elongated, (13.0–)13.5–19.5(–20.0) × (10.0–)11.0–17.5(–18.0) µm [av. ± SD, 16.6 ± 1.6 × 14.1 ± 1.7 µm, n = 170/3]; wall even, 1.0–1.5 µm thick, darker than the rest of spore, without protuberances and light refractive spots, but sometimes with 2–3 weakly visible internal swellings; surface finely verruculose as seen by LM, spore profile smooth, surface finely verruculose as seen by SEM, with very low warts up to 0.2 µm high (measured from SEM micrographs), warts usually single, rarely confluent, interspaces finely punctate.

Other specimens examined (paratypes): — RUSSIA. Kamchatka: Uzernaja River , on Carex pauciflora , 12 Aug. 1921, E . Hultén ( S F-41990!) . U.S.A. Alaska: Kenai Peninsula, 3 miles north of Lower Summit Lake , 60°43´N, 149°28´W, on Carex pauciflora , 18 Aug. 1951, J. A . Calder 6848 ( S F-51667! ex DAOM 28242 ) .

Etymology: — The specific epithet refers to the occurrence of this smut on both sides of the Bering Sea in the Beringia [Latin trans-, across, and Bering Sea].

Host and distribution: — On Carex sect. Leucoglochin : Carex pauciflora Lightf. Known from Russia (Kamchatka) and U.S.A. (Alaska).

Figures

FIGURE 1. Anthracoidea transberingiana on Carex pauciflora (holotype BPI 171459). A. Sorus in the ovary. B–F. Spores seen by LM, median and superficial views, note internal swellings indicated by arrows. G–I. Spores seen by SEM. J. Spore wall seen by SEM. Bars: A = 1 mm, B–F, H = 10 µm, G = 20 µm, I = 5 µm, J = 2 µm.