History of Name:
Laccaria trichodermophora

G. M. Mueller, Mycotaxon 20: 112-114. 1984. Type: U.S.A.: Mississippi, Harrison Co., DeSoto National Forest, Harrison Experimental Forest, Road H-6, 5 December l98O, G. M. Mueller 1062 (TENN 42523) (TENN!, holotype).

Species Synopsis:


Pileus 9-66 mm broad, not striate, often becoming fibrillose-scaly, brownish orange. Lamellae pinkish flesh color. Stipe 20-115 mm long, moderately striate, concolorous with pileus; basal mycelium violet when fresh, soon becoming white. Pileipellis of numerous large fascicle of ± perpendicular hyphae. Basidia 4-sterigmate. Cheilocystidia 20-60 X 2-6.5 µm, filamentous, absent to abundant. Basidiospores mostly 7-8.5 X 6-8 µm (excluding ornamentation), subglobose to broadly ellipsoid, echinulate; spines 0.5-1.8 µm long. Southeastern North America, normally associated with pines.

Habitat and Distribution:


Scattered to gregarious; commonly encountered in southeastern North America; temperate coniferous or mixed coniferous deciduous forests, apparently usually associated with species of Pinus. See Specimens Examined for the list of specimens studied.

Observations:


Laccaria trichodermophora differs from L. laccata by having violet basal mycelium and smaller basidiospores. Its culture mat morphology differs by displaying a faster growth rate and violet coloration on PDA and MMN. Because of the ephemeral nature of the violet pigment in the basal mycelium and the slight overlap of basidiospore size and shape with those of L. laccata var. pallidifolia, it is occasionally difficult to differentiate between dried herbarium specimens of the two taxa.
Laccaria trichodermophora can be distinguished from L. bicolor and L. nobilis by its distribution, basidioma coloration and scant basal mycelium. Additionally, the three taxa have distinct culture mat morphologies. Laccaria bullifera Singer from Mexico is characterized by the occurrence of large, swollen cheilocystidia.
Mueller and Gardes (1991) summarized the results of intercollection pairing studies, phenetic analyses, and analyses of mtDNA and rDNA RFLPs for the L. bicolor complex. They concluded that collections of L. trichodermophora were well delimited from L. bicolor and L. nobilis (see OBSERVATIONS under L. bicolor). The concept of L. trichodermophora used here includes material termed Bi1 and L. trichodermophora in previously published phenetic analyses (Mueller, 1985).
Singer and Moser (1965) and Singer (1973, 1977, 1986) used the name L. farinacea for the taxon herein referred to as L. trichodermophora. No type exists for A. farinaceus and Hudson (1798) listed A. laccatus under A. farinaceus implying that A. farinaceus was only a new name for A. laccatus. Fries (1821) placed A. farinaceus in synonymy under A. laccatus var. "a." In addition, neither Hudson nor Persoon (1801) mentioned the color of the basal mycelium in their description. It was necessary, therefore, to propose a new name for this taxon.
All of the collections of L. trichodermophora observed from the southeastern United States appeared to be associated with Pinus. Laccaria trichodermophora has not been reported from western or midwestern North America. To date, no material referable to L. bicolor sensu stricto nor L. nobilis has been encountered in southeastern North America. Material from the northeastern United States or Atlantic Coast Canada was not included in Mueller and Gardes (1991) and the occurrence of these three taxa in that area is not known. Collections of L. bicolor sensu lato are commonly collected in northeastern North America and are currently treated as L. bicolor. Aguirre-Acosta and Pérez-Silva (1978) and Montoya-Bello et al. (1987) reported L. trichodermophora (as L. farinaceae sensu Singer) from Mexico. Mueller and Strack (1992) have collected L. trichodermophora beneath neotropical species of Quercus in Costa Rica.

Macromorphology:

Pileus 9-66 mm broad, convex to
plane, occasionally becoming uplifted, often depressed, not striate, strongly pruinose to fibrillose, becoming fibrillose-scaly to scaly due to cuticular diffraction, hygrophanous, brownish orange, occasionally reddish brown ("Hazel," "Vinaceous-Rufous," "Auburn," "Orange Rufous," "Cacao Brown" or "Cinnamon-Rufous"), fading light brown to buff color ("Flesh-Ocher" to "Apricot Buff"), occasionally darker reddish brown at disc ("Hay's Russet" to "Kaiser Brown"); margin incurved decurved or plane, entire to undulate, occasionally becoming eroded; context 1-2 mm thick, tapering quickly to margin, pinkish flesh color ("Light Congo Pink" to "Pale Vinaceous-Pink"). Lamellae sinuate to adnate, close to distant, broad, relatively thin to thick, flesh color ("Vinaceous-Pink," "Shell Pink," "Flesh Color" or "Pale Salmon Color"), at times vinaceous in age (near "Vinaceous"). Stipe 20-115 x 2-11 mm, equal, subclavate or slightly bulbous, dry, fibrillose, inconspicuously to moderately longitudinally striate, concolorous with pileus; context stuffed, becoming hollow, concolorous with pileus context. Basal mycelium violet (near "Lavender" or "Pale Violet") when fresh, strongly hygrophanous, fading to white. Basidiospores white in mass.

Micromorphology:


Pileipellis of very numerous large fascicles of ± perpendicular hyphae, often forming a trichodermium in young specimens and at the disc; fascicles composed of 15-30 or more hyphae; terminal cells of fasciculate hyphae 25-73.5 x 6-32 µm, filamentous, clavate or occasionally 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 3-18 µm diam, thin-walled, hyaline to light yellowish brown; cells filamentous to barrel-shaped. Subhymenium morphologically undifferentiated. Basidia 24.5-55 x 7-13(-20) µm, clavate, hyaline; sterigmata 4, up to 9 µm long. Cheilocystidia 17.5-60 x 2-6.5 µm, filamentous, occasionally subclavate, thin-walled, hyaline, absent, scattered or abundant. Basidiospores (excluding ornamentation) [415/20] (6.2-)6.8-8.7(-10.6) x 6-8(-9.2) µm [ = 7.1-8(-8.5) x 6.3-8 µm], Q = 1-1.24(-1.36) [ = (1.01-)1.08-1.17], subglobose to broadly ellipsoid, occasionally globose or ellipsoid, hyaline, echinulate; echinulae (0.5-)0.9-1.8 µm long, irregularly spaced to crowded; hilar appendix 1.3-1.8 µm long, prominent, truncate; plage present; contents occasionally uniguttulate. Basal mycelium hyphae mostly 3-12 µm diam, tightly interwoven, hyaline; cells filamentous to barrel-shaped.

Somatic Culture Mat Morphology
(n=8; Appendix B):

PDA: Radius at week 3 = 15-38 mm or 42-45 mm, week 6 = (23-)29-59 mm or covering agar surface; mat felty, tightly interwoven, uniformly thick or with narrow, thicker dendritic strands radiating out from plug, tightly appressed to agar surface, normally forming pruinose aerial layer away from plug with time, not translucent, bright violet, fading to violet, finally to light orange-brown near plug; aerial hyphae light grayish violet; margin 2-6 mm broad, subfelty, felty or silky, thin to thick, entire to uneven, light violet to white; plug dark violet, soon becoming light orange-brown; hyphae morphologically undifferentiated, occasionally subcoralloid or irregulary swollen. MMN: Radius at week 3 = 24-44 mm or 52-64 mm, week 6 = (43-)54-78 mm or agar surface covered; mat subfelty becoming felty or silky, thin to thick, with 2-3 narrow (2-3 mm), slightly thicker concentric zones or with slightly thicker, radially arranged, dendritic strands or uniformly thin, tightly appressed to agar surface, translucent, light violet, thicker zones somewhat darker; margin not well differentiated from mat, silky to subfelty, sinuate, light violet to white; plug concolorous with mat; hyphae same as in PDA. MEA: Radius at week 3 = 20-42 mm, week 6 = 38 mm or agar surface covered; mat silky to subfelty, thin or thick, occasionally thicker near plug, loosely interwoven or interwoven, tightly appressed to agar surface, translucent, white; margin not well differentiated from mat, silky to subfelty, entire to sulcate, white; plug white; hyphae morphologically undifferentiated, occasionally irregularly swollen.