Macrocybe titans (H.E. Bigelow & Kimbr.) Pegler, Lodge & Nakasone, 1998

Zambrano-Forero, Cristian J, Davila-Giraldo, Lina R, Motato-Vasquez, Viviana, Villanueva, Paula X, Rondon-Barragan, Iang S & Murillo-Arango, Walter, 2023, Diversity and distribution of macrofungi (Ascomycota and Basidiomycota) in Tolima, a Department of the Colombian Andes: an annotated checklist, Biodiversity Data Journal 11, pp. 104307-104307 : 104307

Macrocybe titans (H.E. Bigelow & Kimbr.) Pegler, Lodge & Nakasone, 1998

Materials

Type status: Other material. Occurrence: catalogNumber: LRD 150 ; occurrenceRemarks: coming out under cement plate; occurrenceID: 069737A7-B8EA-5E0C-8C02-ECE1878FB89C; Location: higherGeography: Colombia; Tolima; Municipality of Líbano; verbatimElevation: 1622 m; verbatimCoordinates: 4°55'21.2"N 75°04'32.8"W; Event: eventDate: 25 May 2021; Record Level: collectionCode: FUT

Notes

Macrocybe titans could be confused with Clitocybe gigantea (Fr.) Quélet, but the latter presents a funnel-shaped crown and decurrent lamellae ( Bigelow and Kimbrough 1980, Corrales and López-Q 2005). Macrocybe titans is distinguished macroscopically from other species because the surface of the stipe is visibly squamulose and, microscopically, by having numerous spindle-shaped pseudocystidia, with refractive content ( Pegler et al. 1998). The species has been collected normally in disturbed environments of the Neotropics and has been recorded as edible. At the moment, this species has only been collected in the Departments of Antioquia and Santander in Colombia. This is the first record of the species for Tolima.

Diagnosis

Pileus 4-25 cm broad, hemispherical, broadly convex to flattened; margin incurved at first and later uplifted; abhymenial surface dry, smooth, not hygrophanous, cracking into small appressed squamules, cream to pale yellow (Fig. 1 B). Context thick on disc, compact and whitish. Lamellae crowded, sinuate to adnate with a decurrent tooth, with lamellulae of four different lengths, whitish to cream. Stipe 6-20 × 5-10 cm, cylindrical, central, solid, fleshy; surface white to pale yellow, with numerous and reflexed darker squamules. Pileipellis as a cutis, composed of emerging to erected hyphae 4-6 μm wide. Hymenophoral trama of parallel hyphae, cylindrical to inflated. Generative hyphae with clamps. Pseudocheilocystidia fusoid, with subacute to rostrate or rounded apices, lanceolate to lageniform. Caulocystidia absent. Basidia 4-spored, sterigmata prominent. Spore print cream. Spore s subglobose to ovoid or broadly ellipsoid, smooth, thin-walled, negative in Melzer’s Reagent, 5.8-6.3 × 4.4-5.0 μm, Q = 1.2-1.4 µm.

Figures

Figure 1. Fresh basidiomata of species as new records for the Department of Tolima. A Basidiomata of Nigelia martialis (ZF 27); B Basidiomata of Macrocybe titans (LRD 150); C Basidiomata of Auricularia fuscosuccinea (LRD 36); D Basidiomata of Protomerulius caryae (LRD 117); E Basidiomata of Dacryopinax spathularia (PXVB 10); F Basidiomata of Cotylidia aurantiaca (LRD 138); G Basidiomata of Gloeoporus thelephoroides (LRD 130); H Basidiomata of Irpex rossettiformis (LRD 145); I Basidiomata of Physisporinus lineatus (ZF 35). Scale bars B, C, G = 5 cm; Scale bars A, D, E, F, H, I = 1 cm. Photos by: Cristian Zambrano (A, D, F, G); Lina Davila (B, C); Paula Villanueva (E, H, I).