Collybiopsis orientisubnuda J.S. Kim & Y.W. Lim, 2022

Kim, Ji Seon, Cho, Yoonhee, Park, Ki Hyeong, Park, Ji Hyun, Kim, Minkyeong, Kim, Chang Sun & Lim, Young Woon, 2022, Taxonomic study of Collybiopsis (Omphalotaceae, Agaricales) in the Republic of Korea with seven new species, MycoKeys 88, pp. 79-108 : 79

Collybiopsis orientisubnuda J.S. Kim & Y.W. Lim sp. nov.

Fig. 3G-H

Etymology.

Epithet " Collybiopsis orientisubnuda " meaning the new species has originated from the East and is morphologically similar to Co. subnuda .

Holotype.

The Republic of Korea, Gyeongsangbuk-do: Ulleung-gun, 37°31'21"N, 130°53'14"E, alt. 757 m, 19 July 2016, Changmu Kim, Jinsung Lee, Jae Young Park, NIBRFG0000500990 (GenBank accession no. ITS: OL467262; nrLSU: OL546546).

Diagnosis.

It features a brownish, 15-50 mm pileus, orangish cream-colored lamellae, greyish to brownish orange, tomentose, 20-80 × 2.5-6 mm stipe, subcylindrical to fusoid, 6.7-8.6 × 1.8-3.2 μm basidiospores, and cylindrical, flexuose, sometimes irregular or curved, 26.3-52 (63) × 3.5-6.5 μm caulocystidia. This species is morphologically similar to Co. subnuda .

Description.

Pileus: 15-50 mm, convex to plano-convex, sometimes subumbonate; Surface smooth, brownish orange (6C5 to 7C4), becoming paler to the margin (5A2). Lamellae: distant, L = 16-28, l = 3-7, adnexed, pale yellow (4A3) to orange white (5A2). Stipe: 20-80 (100) × 2.5-6 mm, central to eccentric, cylindrical, tomentose, often twisted, greyish orange (6B4) to brownish orange(7C4), becoming paler and thinner to the base. Basidiospores: 6.7-8.6 × 1.8-3.2 μm (average 7.5 × 2.5 μm), Q = 2.5-3.2 (mean = 2.92), cylindrical to fusoid, smooth, hyaline, non-dextrinoid, with drops. Basidia: (17) 19.8-28.7 (29) × 3.7-7.3 μm, 4-spored, narrowly clavate, often constricted. Cheilocystidia: variable in shape and size, 21-33.3 × 4.7-8.2 μm, lobed, clavate, slightly sphaeropendunculate, sometimes constricted or with rostrate apex. Pleurocystidia: 24.7-52.3 × 5.1-9.1 μm, narrowly utriform, clavate, sometimes clavate with rostrate apex. Trama hyphae: cylindrical, often subinflated, smooth, branched, non-dextrinoid, 2.0-7.0 μm wide. Pileipellis: a cutis made up of cylindrical, 2-8 μm wide hyphae; terminal elements adpressed, cylindrical, often subinflated, with weak annular ornamentation, 3-6 μm wide. Stipitipellis: a cutis of cylindrical, smooth, 2.5-7 μm wide hyphae. Caulocystidia: 26.3-52 (63) × 3.5-6.5 μm, cylindrical, flexuose, sometimes irregular or curved. Clamp connections: present in all tissues.

Other specimens examined.

The Republic of Korea, Chungcheongnam-do: Yesan-gun, Mt. Gaya , 35°48'14"N, 128°5'49"E, alt. 863 m, 23 August 2017, Hae Jin Cho, Ki Hyeong Park, SFC20170823-39. The Republic of Korea, Gangwon-do: Pyeongchang-gun, Mt. Odae , 37°43'54"N, 128°35'42"E, alt. 683 m, 8 July 2017, Nam Kyu Kim, SFC20170708-14. The Republic of Korea, Gyeongsangbuk-do: Ulleung-gun, 37°31'30"N, 130°52'21"E, alt. 718 m, 2 September 2015, Jae Young Park, SFC20150902-01 .

Habit and habitat.

Scattered to gregarious on the ground covered with dead and decaying leaves of broadleaf forest, from summer to autumn.

Distribution.

The Republic of Korea.

Remark.

Collybiopsis orientisubnuda is morphologically similar to Co. peronata (Bolton) R.H. Petersen and Co. subnuda (Ellis ex Peck) R.H. Petersen. Collybiopsis peronata can be distinguished from Co. orientisubnuda by fewer and buff lamellulae (1-3), a thicker stipe (3-8 mm), smaller Q value (2.3), longer basidia (20-40 μm), and longer cheilocystidia (25-90 × 5-10 μm) ( Noordeloos et al. 1999). Collybiopsis subnuda differs from Co. orientisubnuda with thinner stipe (~3 mm), larger basidiospores (8-11 × 3-4.5 μm) and the absence of pleurocystidia ( Tekpınar and Acar 2020).

Figures

Figure 3. Basidiomata and microscopic characters of the four new Collybiopsis species A, B Co. albicantipes (SFC 20170725 - 35) C, D Co. clavicystidiata (SFC 20180705 - 84) E, F Co. fulva (KA 15 - 0210) G, H Co. orientisubnuda (NIBRFG 0000502862). Scale bars: 1 cm (A, C, E, G); 20 µm (B, D, F, H). Abbreviations: s basidiospores; b basidia; ch cheilocystidia; p pleurocystidia; ca caulocystidia.