The North American Species of Crepidotus

28. Crepidotus applanatus var. applanatus (Pers.) Kummer, Der Führer in Pilzk., p. 74. 1871  sensu Josserand.

Agaricus applanatus Pers., Myc. Eur. 3: 30. 1828.

Illustrations: Figs. 5, 6, 78, 79.

Pileus 1-4 cm broad, sessile, flabelliform, petaloid, spathulate, reniform or semi-orbicular, glabrous, at times more or less pubescent, villose or fibrillose at the base, white becoming brownish or somewhat vinaceous to buff or dull cinnamon as the spores mature, hygrophanous, margin striatulate when wet. Context thin, white; odor and taste mild.

Lamellae narrowly adnate-decurrent, white at first, then brownish, close or crowded, narrow, lamellulae numerous, edges fimbriate to even.

Spores in deposit: "Sayal brown" to "cinnamon brown," 4-5 (5.5) µ, globose, punctate. Basidia 22-27 x 6-7 µ, 4-spored. Pleurocystidia none; cheilocystidia 20-40 (50) x 5-10 (12) µ, clavate to ventricose, at times capitate. Gill trama subparallel, hyphae 5-9 µ broad. Pileus trama interwoven. Cuticle of repent hyphae, at times with scattered, erect hyphae and pileocystidia , 25-65 x 5-10 (12) µ, clavate or ventricose. Clamp connections present.

Habit, Habitat, and Distribution: On hardwood, more rarely on conifers, temperate North America and the world, summer.

Material Studied: IDAHO: Smith 53413; MAINE: Bigelow 4113 (MASS), 10572, 10625, 11314, 11328; MASSACHUSETTS: Bigelow 6269 (MASS), 6828, 6829, 6835, 7076, 7077, 9467, 7928; Smith 67283; MICHIGAN: Imshaug 4797 (MICH); Miller 1062 (MICH); Smith 1374, 1500, 16172, 23427, 33225, 33679, 33825, 39518, 41652, 41800, 41811, 57771, 57941, 61199, 63833, 66857, 66858, 66870, 67005, 67074, 67110, 67144, 67146, 67147, 67148, 67149, 67150, 67235; Thiers 3001 (MICH), 3118, 3172, 3475; NEW HAMPSHIRE: Bigelow 12072, 12085, 12168, 12169; NEW YORK: Hesler 9034; Shaffer 513 (MICH); NORTH CAROLINA: Hesler 5115, 21902, 22080, 23089; OHIO: Cooke 32165; TENNESSEE:  Hesler 3673, 8099, 21400, 24852; VERMONT: Bigelow 9907 (MASS); FRANCE: Josserand (TENN 25188).

Observations: We are following Josserand's (1937) concept of the type variety of C. applanatus. The distinguishing characters include a white, sessile pileus, gills white (at first), close and narrow, small spores (4-5.5 µ), no pleurocystidia, and clavate to ventricose cheilocystidia.

The species embraces a complex of forms, some of which are being assigned to proposed new varieties. For those individuals with the above characters but with septate cheilocystidia, we propose the name var. phragmocystidiosus; for those with non-septate, forked or contorted cheilocystidia and pileocystidia , we propose var. diversus. For individuals which have all the characters of var. applanatus except for larger spores (5.5-7.5 µ), we assign the name var. globigera (Berk.) Sacc.

Within the type-variety one finds the usual, or normal, variations. In one Tennessee collection for example (TENN 24852), the fresh pilei had a slightly pungent odor and astringent taste; in a Michigan collection (MICH 57771) a pseudostipe is present, and the cheilocystidia are somewhat longer (up to 67 µ) than usual, as are the pileocystidia . An inconspicuous temporary stipe is reported by several authors.