Laccaria laccata

   

History of Name:
Laccaria laccata var. pallidifolia

(Peck) Peck. Figures 12-14, 54d-f, 68c.

Clitocybe laccata var. pallidifolia Peck, Annual Rep. New York State Bot. 43: 274. 1890. Laccaria laccata var. pallidifolia (Peck) Peck, Annual Rep. New York State Bot. 157: 92. 1912. Laccaria laccata var. decurrens Peck, Annual Rep. New York State Bot. 157: 92. 1912. Laccaria laccata f. minuta Imai, J. Fac. Sci. Hokkaido Imp. Univ., Ser. 5, Bot. 18: 90. 1938. Laccaria laccata var. minuta (Imai) Hongo, Mem. Shig. Univ. 9: 58. 1959.

Laccaria laccata var. anglica Singer, Bull. Soc. Mycol. France 83: 110-111. 1967.

Laccaria anglica (Singer) Bon, Doc. Mycol. 11: 22. 1981 [not val. publ., basionym lacking]. Laccaria affinis var. anglica (Singer) Bon, Doc. Mycol. 13: 50. 1983.

Laccaria laccata var. affinis Singer, Bull. Soc. Mycol. France 83: 111. 1967.
Laccaria affinis (Singer) Bon, Doc. Mycol. 13: 49. 1983.

Laccaria laccata var. chilensis Singer, Bull. Soc. Mycol. France 83: 109. 1967. Laccaria laccata var. subalpina Singer, Pl. Syst. Evol. 126: 365. 1977. Laccaria tetraspora var. peladae Singer, Bull. Soc. Mycol. France 83: 117. 1967. Laccaria laccata var. peladae (Singer) Singer, Pl. Syst. Evol. 126: 366. 1977.

Laccaria laccata var. tatrensis Singer, Pl. Syst. Evol. 126: 367. 1977.
Laccaria laccata var. intermedia Singer, Pl. Syst. Evol. 126: 368. 1977.
Type: U.S.A.: New York, Selkirk, October, C. H. Peck s.n. (NYS!, holotype).

Species Synopsis:



Pileus mostly 10-45 mm broad, not striate to striate, orange brown when fresh, becoming buff. Lamellae pinkish flesh color. Stipe mostly 20-65 mm long, often finely striate, concolorous with pileus; basal mycelium white. Pileipellis interwoven with scattered fascicles of ± perpendicular hyphae. Basidia 4-sterigmate. Cheilocystidia 23-55 X 2.5-7.5 µm, undifferentiated to subclavate, absent to abundant. Basidiospores mostly 7.5-10 X 7-10 µm (excluding ornamentation), globose to subglobose, occasionally broadly ellipsoid, echinulate; spines mostly 1-2 µm long, * 1 µm wide at base. Found throughout North America.

Habitat and Distribution:



Solitary to gregarious, occasionally caespitose, associated with Pinaceae, Fagaceae and Betulaceae; cosmopolitan; abundant. Collected throughout North America. See Specimens Examined for a list of specimens studied.

Observations:



Laccaria laccata var. pallidifolia is characterized by having small- to moderate-sized, orange-brown, glabrous to finely scaly basidiomata, and basidia that bear four globose to subglobose, moderately echinulate basidiospores.
Mueller and Vellinga (1986) and Mueller (1991a) included collections now treated as L. ohiensis (= L. tetraspora) within the concept of this taxon. Reasons for this given by Mueller and Vellinga (1986) included: 1) the macro- and micromorphology of several of the proposed varieties intergraded between the two putative species; 2) basidioma and basidiospore size, as well as basidiospore ornamentation length, appeared to form a continuum for collections in this group; and 3) somatic culture mat morphology did not appear to vary between isolates referable to either of these taxa. It was not possible for Fries and Mueller (1984) to distinguish between collections of the two intersterility groups (Mating groups III & IV) that they detected within the tested Swedish material of L. laccata using basidioma and basidiospore size and basidiospore ornamentation length.
Several additional intersterility groups have since been detected within North America (Mueller, 1991c). Each of these groups were found to differ markedly in RFLPs of mtDNA and rDNA (Gardes et al., 1990, 1991a). Subsequent morphometric analyses have shown that collections of some of these intersterility groups, but not others, were segregated during morphometric analyses of basidiospore data (Mueller, 1991c). Two groups were clearly delimited during morphometric analyses; one group consisted of collections with globose basidiospores with echinulae > 1.5 µm long and > 1.2 µm wide at the base while the other group consisted of specimens with globose to subglobose basidiospores with echinulae 0.7-2 µm long and * 1 µm wide at the base (Mueller, 1991c). The first group consisted of collections referable to L. ohiensis and L. striatula while collections in the second group are referable to either L. laccata var. pallidifolia, L. laccata var. moelleri, or L. longipes.
Laccaria laccata var. pallidifolia is differentiated primarily from L. ohiensis by having narrow basidiospore echinulae. Collections of L. laccata var. pallidifolia with small basidiomata and globose basidiospores (characteristics of L. ohiensis) are occasionally encountered.
Laccaria laccata var. pallidifolia is differentiated from L. striatula on differences in basidiospore ornamentation and macromorphological features. Collections of L. striatula have relatively long, glabrous stipes which are usually darker than the strongly striate pileus.
Laccaria laccata var. pallidifolia is differentiated from L. longipes by having shorter stipes and larger basidiospores.
Laccaria laccata var. pallidifolia is the most commonly encountered taxon in the complex and can be found throughout the United States and Canada. No apparent habitat preference could be determined from the material collected during this study.

Macromorphology:



Pileus 10-45(-60) mm broad, obtuse to convex, often becoming plane to uplifted, often depressed, striate to not striate, occasionally strongly striate to plicate-striate, sometimes translucent-striate when fresh, finely fibrillose to fibrillose-scaly, infrequently slightly scaly, hygrophanous, orange-brown when fresh, becoming buff color ("Sanford's Brown," "Orange Rufous," "Hazel," "Cinnamon Rufous," "Pinkish Cinnamon" or "Light Vinaceous-Cinnamon"), fading lighter ("Apricot Buff," "Salmon Color," "Light Pinkish Cinnamon" or "Pinkish Buff"), finally to buff ("Pale Ochraceous Buff"); disc occasionally darker orange-brown or red-brown ("Hay's Russet," Ochraceous Tawny" or "Buckthorn Brown"); margin incurved to decurved, becoming plane to uplifted, entire to undulate, occasionally becoming eroded in age; context thin, tapering quickly to margin, concolorous. Lamellae sinuate, adnate or arcuate, rarely decurrent, close to distant, narrow to broad, relatively thin to thick, pinkish flesh color ("Flesh Color," "Salmon-Buff," "Pale Salmon Color," "Flesh-Pink" or "Light Vinaceous-Cinnamon"), some becoming slightly vinaceous with age (near "Light Grayish-Vinaceous"). Stipe (12-)20-65(-106) x 2-4(-8) mm, equal, subclavate or tapering towards base, occasionally slightly bulbous, dry, fibrillose, not striate to finely longitudinally striate, rarely with pronounced striations, concolorous with stipe; context stuffed, becoming hollow, concolorous with pileus context. Basal mycelium sparse to copious, always white. Basidiospores white in mass.

Micromorphology:


Pileipellis of interwoven hyphae with widely scattered fascicles of ± perpendicular hyphae; fascicles composed of 5-15(-30) hyphae; terminal cells of fascicular hyphae 6-101 x 3-37.5 µm, filamentous, subclavate, clavate, subcapitate or ventricose-rostrate; 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 2-17.5 µm diam, thin-walled, hyaline to light yellowish brown; cells filamentous to barrel-shaped. Subhymenium morphologically undifferentiated. Basidia 27.5-55 x 7.5-13.5(-16.5) µm, clavate, hyaline; sterigmata 4, up to 7 µm long. Cheilocystidia 23-55 x 2-7.5 µm, filamentous to subclavate, occasionally strangulate, absent or scattered to abundant, thin-walled, hyaline. Basidiospores (excluding ornamentation) [1000/65] (6.4-)7.4-10(-13) x (6-)7-10(11.5) µm [ = (7.3-)8.2-9(-9.6) x (6.7-)7.6-8.6 µm], Q = 1-1.13(-1.3) [ = 1-1.15(-1.2)] , globose to subglobose, occasionally broadly ellipsoid, hyaline, echinulate; echinulae (0.5-)1-2 µm long, * 1 µm wide at base, relatively scarce to crowded; hilar appendix 1.3-2.2 µm long, prominent, truncate; plage present; contents occasionally uniguttulate or biguttulate. Basal mycelium hyphae mostly 3-10.5 µm diam, tightly interwoven, hyaline; cells filamentous to barrel-shaped.

Somatic Culture Mat Morphology
(n=11; Appendix B):


PDA: Radius at week 3 = 7-23 mm or 62-73 mm, week 6 = 18-27 or 90 mm (agar surface covered); mat felty, thick, tightly interwoven, some appearing almost crustose, tightly appressed to agar surface, occasionally forming cottony to felty aerial layer away from plug, not translucent, white, in some becoming dark olive brown or light chocolate color away from plug; margin narrow to moderately broad, silky to subfelty, thin, white, entire to undulate; plug occasionally covered with cottony white hyphae or with long serial aggregations of hyphae growing away from top of plug, white, often becoming dark olive brown or light chocolate color; hyphae morphologically undifferentiated, rarely irregularly swollen. MMN: Radius at week 3 = 13-19 mm or (25-) 29-52 mm, week 6 = 26-45 mm or 75 mm to covering agar surface; mat subfelty, felty or silky, moderately thick, interwoven, in one isolate (TENN 42964) with several radially arranged pie shaped thicker sectors, tightly appressed to agar surface, translucent, white; margin narrow, silky to subfelty, not well differentiated, even to undulate, occasionally somewhat serrate, white; plug white; hyphae morphologically undifferentiated, occasionally coralloid. MEA: Radius at week 3 = 12-33 mm or 53-62 mm, week 6 = 23 54 mm or covering agar surface; mat silky to subfelty, thin to moderate, appearing combed to loosely interwoven, occasionally becoming thicker near plug, tightly appressed to agar surface, translucent, white; margin not well differentiated, thin, entire to slightly serrate, white; plug white; hyphae morphologically undifferentiated.