Laccaria nobilis

 

History of Name:
Laccaria nobilis

Smith apud G. M. Mueller, Mycotaxon 20: 105-108. 1984. [Laccaria nobilis Smith, nom. herb.]. Type: U.S.A.: Colorado, Larimer Co., Roosevelt National Forest, Rayah Wilderness, Blue Lake Trail, 13 September 1981, G. M. Mueller 1198 (TENN 42527) (TENN!, holotype).

Species Synopsis:



Pileus 16-85 mm broad, not striate, fibrillose-scaly, becoming scaly to squarrose, reddish brown to brownish orange. Lamellae vinaceous to pinkish flesh color. Stipe up to 110 (-160) X 10 (-16) mm, strongly fibrillose, longitudinal striate, occasionally reticulate, concolorous with pileus; basal mycelium violet. Basidia 4 sterigmate. Cheilocystidia lacking. Basidiospores mostly 6.5-10 X 6-9 µm (excluding ornamentation), most subglobose to broadly ellipsoid, echinulate; spines <0.5-1.4 µm long. Western North America east to the Great Lakes, under conifers.

Habitat and Distribution:



Solitary to scattered. Infrequently encountered under Pinaceae in western North America and areas adjacent to the Great Lakes. See Specimens Examined for the list of specimens studied.

Observations:



Laccaria nobilis can be distinguished easily from other members of the L. bicolor complex by its large size, scaly to squarrose pileus, scaly stipe, and lack of obvious cheilocystidia. A. H. Smith proposed the name in an unpublished manuscript along with several other taxa including L. pisciodorus nom. prov.(Smith no. 18812) and L. sphagnicola nom. prov. (Smith no. 4573). The latter two taxa were not judged sufficiently distinct, based on available material, to justify valid publication as discrete taxa.
The concept of L. nobilis used here has been broadened from that originally published by Mueller (1984; 1985). Interpretation of lamellae and basal mycelium colors was difficult in many of the collections included in the original description because the specimens were mature and weathered. Additional material was collected subsequently which differed from the original collections in having vinaceous lamellae and violet mycelium at the base of their stipe. Since all of these collections had large-sized, robust basidiomata which became quite scaly in age, strongly striate to nearly reticulate stipes, similar micromorphology and somatic culture mat morphology, they were treated as a single taxon, L. nobilis. Isolates of more recently collected specimens were included among the material studied by Mueller and Gardes (1991).
Laccaria nobilis is well delimited from L. bicolor and L. trichodermophora based on intercollection pairing studies, phenetic analyses, and analyses of mtDNA and rDNA RFLPs (Mueller and Gardes, 1991) (see OBSERVATIONS under L. bicolor).
Laccaria nobilis has been identified among material collected throughout much of western North America (e.g., California, Colorado, Idaho, New Mexico, Oregon and Washington) and from Michigan and Ontario.

Macromorphology:



Pileus 16-85 mm broad, convex to plane, occasionally becoming uplifted, depressed to deeply depressed, not striate, fibrillose-scaly becoming scaly to squarrose, reddish brown (8C7-8D7) to brownish orange ("Sanford's Brown" or "Cinnamon- Rufous") (6C7, 7C6-7D7), occasionally darker at disc ("Hazel"); margin incurved, decurved or plane, occasionally upturned, entire to eroded; context thin, concolorous with lamellae. Lamellae sinuate to adnate, close to distant, thick, vinaceous (8B2-9B3) to pinkish flesh color ("Flesh Color," "Pale Flesh Color" or "Orange-Pink") (7A2-7A3). Stipe (21-)26-110(-160) x 4-10(-16) mm, equal, slightly bulbous or subclavate, dry, fibrillose, with prominent longitudinal striations or reticulate ridges, often with apical recurved scales at maturity, concolorous with pileus; striations concolorous with stipe ground color or somewhat darker reddish brown. Basal mycelium violet, soon becoming white. Basidiospores white in mass.

Micromorphology:


Pileipellis of interwoven hyphae with scattered fascicles of ± perpendicular hyphae; fascicles composed of 15-30 or more hyphae; terminal cells of fascicular hyphae 34.5-75 x 4-19 µm, subclavate, clavate, broadly clavate or capitate; walls up to 0.5 µm thick, light yellowish brown; contents hyaline to light yellowish brown. Pileus trama tightly interwoven, morphologically undifferentiated, hyaline, light yellowish brown toward pileipellis. Lamellar trama parallel; hyphae mostly 3-10 µm diam, thin-walled, hyaline to light yellowish brown; cells barrel-shaped. Subhymenium morphologically undifferentiated. Basidia 32-55 x 8-14 µm, clavate, hyaline; sterigmata 4, up to 9 µm long. Cheilocystidia lacking. Basidiospores (excluding ornamentation) [122/8] (6.2-)6.6-9.7(-10.6) x (5-)6.2-8.7 µm [ = (7-)7.4-8.8 x (6-)6.3-7.8 µm], Q = 1-1.26(-1.39) [ = (1.03-)1.16-1.22], subglobose to broadly ellipsoid, occasionally globose or ellipsoid, hyaline, echinulate; echinulae 0.5-1.4 µm long ( = 0.9 ± 0.2 µm), crowded; hilar appendix 1.3-2 µm long, prominent, truncate; plage present; contents occasionally uniguttulate. Basal mycelium hyphae mostly 2-12 µm diam, tightly interwoven, hyaline; cells filamentous to barrel-shaped.

Somatic Culture Mat Morphology
(n=2; Appendix B):



PDA: Radius at week 3 = 23-31 mm, week 6 = 35-43 mm; mat felty, thick, tightly interwoven, almost crustose, tightly appressed to agar surface, with time forming pruinose aerial layer away from plug, not translucent, at first bright violet, by week 6 violet color restricted to a 7-9 mm band near margin, rest of mat light orange-brown; pruinose aerial hyphae light grayish purple becoming light orange-brown; margin 3-4 mm broad, subfelty, thin, uneven, light violet to white, plug concolorous with mat; hyphae morphologically undifferentiated, occasionally irregularly swollen, purplish brown in mass. MMN: Radius at week 3 = 40-47 mm, week 6 = 67-78 mm; mat subfelty, thin, slightly thicker with age, loosely to tightly interwoven, tightly appressed to agar surface, translucent, light violet, in time color restricted to 3-4 mm band at midpoint, remainder of mat white; margin 3-6 mm broad, silky to subfelty, thin, parallel to loosely interwoven, entire, light violet to white; plug concolorous with mat; hyphae morphologically undifferentiated, rarely irregularly swollen near margin. MEA: Radius at week 3 = 33-47 mm, week 6 = 47-77 mm; mat subfelty, thin to slightly thicker near plug, loosely interwoven, tightly appressed to agar surface, translucent, white; margin 1-2 mm broad, subfelty, thinner than mat, undulate; hyphae morphologically undifferentiated.