Cortinarius bovarius Liimat. & Niskanen

Liimatainen, Kare & Niskanen, Tuula, 2013, Cortinarius bovarius (Agaricales), a new species from western North America, MycoKeys 7, pp. 23-30 : 26-28

Cortinarius bovarius Liimat. & Niskanen sp. nov. Figures 2 and 3

Diagnosis.

Basidiomata medium-sized to large, pileus reddish brown, smell in lamellae indistinct or slightly raphanoid. Universal veil at first white, becoming pale brown. Basidiospores 8.5-10 × 5.5 –6(– 6.5) μm, amygdaloid to weakly ellipsoid. In coniferous forests with Picea , on rich, calcareous ground. Belongs to sect. Bovini .

Description.

Pileus 3.5-7 cm diam., hemispherical at first, then low convex to almost plane, sometimes with a low, broad umbo, weakly fibrillose when young, later more apparent fibrillose only on the margin, somewhat waxy-glossy when moist; when young light reddish brown (5YR 6/4) to yellowish red (5YR 5/6-4/6) to reddish brown (2.5YR 5/4-4/4, 5YR 5/4-4/4), later dark red (2.5YR 3/6) to dark reddish brown (5YR 3/4-4/4, 2.5YR 3/3-3/4) and often with black spots; hygrophanous, soon drying from the center like Kuehneromyces mutabilis to lighter and more reddish brown, in dry condition reddish yellow (5YR 6/6, 7.5YR 7/6-6/6). Lamellae medium spaced to almost distant, adnexed to emarginate, fairly broad to broad, light reddish brown (5YR 6/4), light brown (7.5YR 6/3-6/4) to yellowish red (5YR 4/6), later dark reddish brown (2.5YR 3/4, 5YR 3/4-4/4), edge paler or concolorous. Stipe 5-11 cm long, 0.8-1.7 cm wide at apex, 1-3.5 cm wide at base, clavate to almost bulbose, rarely cylindrical, grayish white (silky) fibrillose, soon light reddish brown (5YR 6/3-6/4) to reddish brown (5YR 5/4) when older. Universal veil at first white, becoming pale brown, forming a girdle and thin sock-like sheath or rarely incomplete girdles on stipe surface, almost completely lost with age. Basal mycelium white. Context marbled hygrophanous, in pileus and upper part of the stipe light reddish brown (5YR 6/3-6/4) to reddish brown (5YR 4/4, 5/3), darkening towards the base of the stipe, in base reddish brown (5YR 5/3) when young, dark reddish brown (2.5YR 3/4 to 5YR 3/3-3/4) when old. Odor indistinct or slightly raphanoid. Exsiccatae: pileus brown (7.5YR 4/2-4/3) to dark brown (7.5YR 3/2-3/3), sometimes with a black center; stipe very pale brown (10YR 8/2) to light gray (10YR 7/2), in older basidiomes often darker, from grayish brown (10YR 5/2) to dark brown (10YR 4/2).

Basidiospores8.5-10 × 5.5 –6(– 6.5) μm, Q = 1.45-1.65, av. = 8.9-9.5 × 5.7-6.1 μm, Qav. = 1.49-1.62 (80 spores, 4 specimens, Fig. 3), amygdaloid to weakly ellipsoid, moderately verrucose, somewhat more strongly so at the apex, moderately dextrinoid. Lamellar trama hyphae smooth to very finely scabrous, sometimes with sepia colored spots. Basidia4-spored, 30-40 × 7.5-9.5 μm, almost concolorous with the background to olivaceous brownish.Pileipellis duplex, epicutis thin, hyphae 3-9 μm wide, unevenly pale brown, pigment in granules or in walls of hyphae, hypoderm distinct, elements 30-55 × 15 –25(– 30) μm, hyaline and smooth. Clamp connections present.

Ecology and distribution.

In mesic coniferous forests with Picea , on rich, calcareous soil. Known from U.S.A, Alaska and Canada, Alberta. Fruiting from late August to September.

Etymology.

bovarius for its affinity to Cortinarius bovinus .

Type.

U.S.A. Alaska: Fairbanks, University campus NW, trails starting from the end of Yukon road, mesic, mossy, partly needle/leaf covered Picea dominated forest with some Populus , Betula , Alnus and Salix , on rich ground, 64°51'33"N, 147°49'29"W, 22 Aug 2011, Niskanen & Liimatainen 11-188 (H, holotype; NY, isotype). GenBank no. KC905156 (ITS), KC905160 (rpb2).

Other specimens examined.

Canada, Alberta, Hinton, S of center, Road to Percotte Creek, old mossy Picea dominated forest with some Populus , on calcareous ground, 53°21'53"N, 117°33'29"W, 30 Aug 2011, Liimatainen & Niskanen 11-298 (H). Alberta, Hinton, N of Athabasca river, Populus dominated forest with some Picea , 53°22'48"N, 117°51'35"W, 1040 m a.s.l., 5 Sept 2011, leg. L. Gagnon, Niskanen 11-373 (H). U.S.A. Alaska, Fairbanks, Wedgewood Resort trails, mesic Picea dominated forest with some Betula and Populus , on calcareous ground, 64°51'41"N, 147°42'46"W, 25 Aug 2011, Liimatainen & Niskanen 11-255 (H).

Discussion.

Cortinarius bovarius is a typical member of section Bovini , a brown species with at first a white universal veil that later becomes brownish, indistinct or slightly raphanoid smell, and occurrence on calcareous ground. It differs from its European sister species, Cortinarius bovinus , by on average narrower, less dextrinoid and less verrucose spores (those of Cortinarius bovinus on average 6.1-6.4 μm wide, fairly strongly to strongly verrucose at the apex, and fairly strongly dextrinoid). The other known species of section Bovini s. str. from western North America, Cortinarius oulankaensis , has a more grayish brown pileus, more distant lamellae, and relatively narrower spores (Qav. = 1.61-1.65). Cortinarius bovarius is a well-defined species based on morphology and molecular data, and therefore, is here describe as new to science.