Macroscopic feat.:

• Cap/Pileus: 10-22 mm diam., convex or conical to papillate, smooth, transparently striate at the margin when moist, viscid, hygrophanous, reddish brown to faded sordid pallid chamois with brownish buff to alutaceous center; pellicle separable.
• Gills/Lamellae: Sinuate-adnate or subadnate, grayish violet but with whitish edges when young.
• Stem/Stipe: 25-45 x 1-2 mm, whitish from a silky appressed covering over a gray background, becoming grayish cinereous where touched: at base soon caesious, slightly and gradually tapering upwards. Veil well formed; annulus membranous but thin, smooth, white, slightly staining blue, fragile but usually persistent.
• Context: Pallid in pileus, grayish to brownish in stipe.
• Odor: None or slightly farinaceous; taste slightly farinaceous.

Microscopic feat.:

• Basidio/Spores: Spore print deep violaceous. (8.8-) 9.9-11 (-12) x 6-6.6 (-7.1) x 5.5-6 µm, subrhomboid frontally, subelliptic in profile, yellowish brown, smooth, more or less thin walled but with complex wall and with broad truncate germ pore.
• Basidia: 15-22.4 x 7.5-9.8 µm, four-spored, hyaline, subvesiculose.
• Pleurocistidia: None.
• Cheilocystidia: 17-20 x 5-6 µm, forming a sterile band on the edge of the gill, hyaline, lageniform or vesiculose-ventricose, the neck 5-8.5 x 1-2 µm, sometimes with an oily hyaline drop at the apex.
• Subhymenium: With parallel, brownish, thin (4 µm diam.) hyphae.
• Trama: Regular, brownish or hyaline, with chestnut incrusted hyphae, 12-20 µm, thin walled. Clamp connections present.
• Hypodermium: With interwoven brownish hyphae which are broader on the average than those of the epicutis, not subcellular, but in the context below often more pigmented and darker, more irregular and with quite a few rather short elements.
• Epicutis: Hyaline, 50-60 µm thick layer of strongly gelatinized hyaline, filamentous hyphae 0.5-2.2 µm thick.

Habitat: On marshy ground or in grasslands outside the forests of Araucaria and Podocarpus, in pasture land, sometimes on dung. Known from Brazil and Uruguay.

Studied material: BRAZIL, State of Sao Paulo, near Campos de Jardao, March 8, 1971, 1600 m elevation, Guzmán 8877 (ENCB; SP). Guzmán 8916 (ENCB; SP). Santa María, 1936, Rick (PACA 15234, Type of Stropharia siccipes var. lugubris Rick). Sao Leopoldo, 1934, Rick (PACA 9362, as Stropharia inucta). Without locality: Rick (Herb. Bresadola 287; NY, as Stropharia luteonitens). URUGUAY, Maldonado, May 27, 1966, Singer B-4172 (BAFC Holotype).

Discussion: Psilocybe caeruleoannulata is close to Psilocybe stuntzii Guzmán & Ott and Psilocybe uruguayensis Sing. ex Guzmán, but differs in the shorter cheilocystidia (Psilocybe stuntzii has cheilocystidia 22-27.5 µm a Psilocybe uruguayensis 24.5-32 µm. This species was named by Singer in the herbarium BAFC based on the collection from Uruguay. Later the author of the present paper collected the same fungus in Brazil and found the species in the herbarium PACA as Stropharia siccipes Karst. var. lugubris Rick, a variety described in 1939 but not considered in Rick's later papers (1961); this material agrees well with the type of Psilocybe caeruleoannulata; the variety of Rick is considered synonymous. Bresadola confused Psilocybe caeruleoannulata with Psilocybe luteonitens (Vahl ex Fr.) Parker-Rhodes, as the author noted in one of Rick's collections (NY), identified by Bresadola as Psilocybe luteonitens, but this species has spores 15.4-18.7 (-20) x 11-13.2 x 9.9-11 µm.

source - www.mycotaxon.com [7 (2): 235-236]

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