History of Name:
Laccaria vinaceobrunnea

G. M. Mueller, Mycotaxon 20: 114-115. 1984. Type: U.S.A.: Louisiana, Tammany Parish, Fountainbleu State Park, under Quercus virginiana, 9 December l98O, G. M. Mueller 1120 (TENN 42525) (TENN!, holotype).

Species Synopsis:


Pileus mostly 7-25 mm broad, not striate, hygrophanous, bright purple when young and fresh, soon becoming vinaceous to reddish brown, eventually fading to buff. Lamellae purple. Stipe 7-56 X 2-7 mm, fibrillose, concolorous with pileus; basal mycelium violet. Pileipellis interwoven with very numerous ± perpendicular individual large hyphae, almost a palisadoderm. Basidia 4-sterigmate. Cheilocystidia 31-92 X 5.5-11 µm, undifferentiated to clavate, very abundant. Basidiospores mostly 7.4 -10 X 6.4-9.2 µm (excluding ornamentation), subglobose to broadly ellipsoid, echinulate; spines 0.5-1.8 µm long, * 1 µm wide at base. Gulf Coast States under live oak.

Habitat and Distribution:


Scattered to gregarious, often caespitose. Growing in sandy soil under Quercus virginiana Miller along the Gulf Coast. See Specimens Examined for the list of specimens studied.

Observations:


Laccaria vinaceobrunnea can be distinguished from L. amethystina and L. amethysteo-occidentalis by habitat, coloration, unique pileipellis and subglobose to broadly ellipsoid basidiospores. The abundant, large cheilocystidia makes a reliable character to use in identifying herbarium collections which lack notes on macromorphology.
Homokaryotic isolates of L. vinaceobrunnea were intersterile with tested isolates of other taxa, including L. amethystina and L. amethysteo-occidentalis.
Material referable to this taxon has not been reported from outside of the Gulf Coast area. Although not yet reported, I would expect it to be found in northeastern Mexico.

Macromorphology:


Pileus 7-25(-42) mm broad, obtuse to convex, becoming plane to uplifted, often depressed, not striate or finely striate when wet, finely fibrillose, occasionally finely fibrillose-scaly, hygrophanous, when immature violaceous (near "Purplish Lilac"), becoming vinaceous (Dark Vinaceous-Brown," "Hay's Brown" or "Vinaceous-Brown"), reddish brown ("Cameo Brown" to "Walnut Brown") then fading to orange-brown or buff ("Cinnamon-Rufous" to "Light Ochraceous-Buff"); margin decurved to plane, entire to eroded; context thin, tapering to margin, light vinaceous ("Light Brownish Vinaceous" to near "Vinaceous-Fawn"). Lamellae adnate to arcuate, subdistant to distant, broad, thick, waxy, purple ("Purplish Lilac" or "Purplish Vinaceous"). Stipe 7-56(-98) x 2-7 mm, equal, subclavate or slightly bulbous, dry, fibrillose, occasionally with recurved fibrils or finely striate, concolorous with pileus; fibrils ("Hazel" or "Vinaceous-Brown"). Basal mycelium violet. Basidiospores white in mass.

Micromorphology:


Pileipellis of interwoven hyphae with very
numerous ± perpendicular hyphae; terminal cells 32-78 x 7-14.5 µm, filamentous to clavate, hyaline to light vinaceous; walls up to 0.5 µm thick; contents hyaline. Pileus trama tightly interwoven, morphologically undifferentiated, hyaline to light olive brown in mass. Lamellar trama parallel; hyphae thin-walled, hyaline; cells barrel-shaped. Subhymenium morphologically undifferentiated. Basidia 33-60 x 8.5-9 µm, clavate, hyaline; sterigmata 4, up to 9 µm long. Cheilocystidia 31.5-92 x 5.5-11 µm, filamentous to clavate, abundant, hyaline. Basidiospores (excluding ornamentation) [60/4] (7-)7.4-10(-10.6) x 6.4-9.2(-9.7) [ = 8.2-8.9 x 7.3-8.3 µm], Q = 1-1.26 [ = 1.07-1.15], subglobose to broadly ellipsoid, occasionally globose, hyaline, echinulate; echinulae 0.5-1.8 µm long, * 1 µm wide at base; hilar appendix 1.3-1.8 µm long, prominent, truncate; plage present; contents occasionally uniguttulate. Basal mycelium hyphae mostly 3-8 mm diam, filamentous, tightly interwoven, hyaline.