Collybiopsis melanopus R. H. Petersen, Mycotaxon 2021
Creators: name: Kumla, Wiphawanee Phonrob Jaturong
name: Suwannarach, Nakarin
name: Khuna, Surapong
name: Nutaratat, Pumin
name: Wannathes, Nopparat
name: Lumyong, Saisamorn
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Fungi
Basidiomycota
Agaricomycetes
Agaricales
Marasmiaceae
Collybiopsis
Collybiopsis melanopus

description: Collybiopsis melanopus (A.W. Wilson, Desjardin & E. Horak) R.H. Petersen,
Mycotaxon 136(2): 342 (2021) FIGURE 7 Index Fungorum number: IF556191
Pileus 12–20 mm diam., convex, expanding to plano-convex, rugulose-striate surface dull, dry, glabrous, disc brownish orange (7C5–7), margin paler to light orange (6A3–4) to beige (5A3). Context up to 1 mm thick, soft. Lamellae adnate, close to sub distant with 2–3 series of lamellulae, narrow, pale cream (4A3). Stipe 21–38 × 1.5–2 mm, central, cylindrical to tapering upwards, fistulose-stuffed, tough, sub insititious; surface dull, dry, white-pruinose overall, apex brownish grey (5–6C3), base dark brown to black; rhizomorphs absent. Odor and taste indistinct.
Basidiospores [25/1/1] 7–8.5 × 3.5–4.5 μm, [x̄ = 7.72 ± 0.56 × 3.9 ± 0.28 µm, Q = 1.75–2.43, Q m = 1.98 ± 0.19], ellipsoid, smooth, hyaline, inamyloid, thin-walled. Basidia 23–30 × 5–7 μm, clavate, smooth, hyaline, inamyloid. Pleurocystidia absent. Cheilocystidia 43–68 × 21–28 μm, clavate to fusiform, broadly obtuse, hyaline, inamyloid, thin-walled. Pileipellis a cutis of radially arranged, repent hyphae 4–6 μm, cylindrical, non-diverticulate, smooth or brown-incrusted, hyaline, inamyloid, non-gelatinous, thin-walled; terminal cells undifferentiated. Pileus trama radially arranged to interwoven; hyphae similar to pileipellis but up to 10 μm diam. Lamellar trama regular; hyphae 3.5–16 μm diam., cylindrical to inflated, hyaline, inamyloid, thin-walled. Stipitipellis a cutis with numerous clustered caulocystidia; cortical hyphae 2.5–8 μm diam., cylindrical, non-diverticulate, smooth or weakly brown-incrusted, hyaline to brown, inamyloid, thin-walled; medullary hyphae 4–16 μm diam., cylindrical to inflated, smooth, hyaline, inamyloid, thin-walled. Caulocystidia 43–54 × 5.5–9 μm, irregularly cylindrical to clavate, flexuose, hyaline, inamyloid, thin-walled. Clamp connections are present in all tissues.
Habitat and known distribution:—Fruiting scattered to gregarious on bark. Known from Africa (São Tomé) (Desjardin & Perry 2017), China (Hu et al. 2022), India (Dutta et al. 2015), Indonesia (Java) (Desjardin et al. 2004), and Thailand (This study).
Material examined:— THAILAND, Chiang Mai Province, Chiang Mai University, 18°48´7´´N 98°57´23´´E, elevation 330 m, on bark, 10 August 2022, W. Phonrob, SDBR-CMUWP072.
Notes:—Thai materials have macroscopic and microscopic features well agree with descriptions of previous studies (Desjardin et al. 2004, Dutta et al. 2015, Desjardin & Perry 2017). Thai materials were grouped with C. melanopus with strong statistical support (BS = 100% and PP 1.00) (FIGURES 2 and 3). Collybiopsis melanopus forms a sister clade to C. juniperina; however, C. juniperina differs from C. melanopus by its darker reddish-brown pileus, wider basidiospores (7.2–9.6 × 4.0–5.2 μm) and presence of diverticula of pileipellis (Mata et al. 2004b). In addition, C. juniperina was distributed in Argentina, Jamaica, and the USA (Horak 1968, Singer 1973, Mata et al. 2004b, Petersen & Hughes 2016, 2021).
description: Published as part of Kumla, Wiphawanee Phonrob Jaturong, Suwannarach, Nakarin, Khuna, Surapong, Nutaratat, Pumin, Wannathes, Nopparat & Lumyong, Saisamorn, 2024, Five new records of Collybiopsis (Agaricales, Omphalotaceae) in Thailand: a significant addition to the species diversity and global distribution of the genus, pp. 213-235 in Phytotaxa 650 (3) on pages 228-229, DOI: 10.11646/phytotaxa.650.3.3, http://zenodo.org/record/13367205