Fleshy Fungi of New Brunswick >> Gymnopus androsaceus

Gymnopus androsaceus (L.) J.L. Mata & R.H. Petersen

Two collections:

• 1. Solitary on a branch of Acer saccharum in forest dominated by Abies balsamea, Acer saccharum, Populus grandidentata and Picea rubens, Spednic Lake Protected Natural Area, New Brunswick (12-08-17/04).

  • Basidiospores white in spore print, dacryoid, smooth, inamyloid, 6.4-7.5 X 3.1-4.5 µm, Q = 1.45-2.22 (average[28]: 6.8 X 3.6 µm, Q = 1.89). Cheilocystidia occurring as a continuous layer of broom cells, strongly coralloid. Pileipellis a repent and interwoven layer of hyphae bearing scattered brown broom cells.

• 2. Gregarious (2) on a highly rotted and moss-covered conifer log in forest dominated by Abies balsamea and Picea mariana, arising from needles of Abies balsamea accompanied by thin rhizomorphs, Kennedy Lakes Protected Natural Area, New Brunswick (30-06-19/05).

  • Basidiospores not forming a spore print, dacryoid, smooth, neither amyloid nor dextrinoid, 5.5-8.1 x 3.0-3.9 µm, Q = 1.74-2.19 (average[40]: 7.0 x 3.5 µm, Q = 2.01. Cheilocystidia not seen (but they should be there – Gilliam [Mycotaxon 4:1-144, 1976] and Noordeloos [Flora Agaricina Neerlandica 3:146, 1995] both illustrate “broom cells” at the edges of the lamellae – maybe this material is overmature). Pleurocystidia lacking. Pileipellis a thin cutis, loosely interwoven in surface view, with hyphae brown-encrusted toward the disc and hyaline and unencrusted elsewhere, with lobed to coralloid protuberances. Basidia 4-spored, not clamped at the base.

Often called the "horsehair fungus" because of the hair-like rhizomorphs accompanying its basidiomata, Gymnopus androsaceus is commonly found in our forests growing on the fallen needles, leaves and twigs of conifers and hardwoods. It is a rather unusual species of its genus, more closely resembling a species of Marasmius than a Gymnopus. However, Mata and Petersen (Mycoscience 45:214-221. 2004), using DNA sequences, showed that it fell in with other species of Gymnopus rather than those of Marasmius.

Microscope mounts of the lamellae of Collection 30-06-19/05 failed to reveal any cheilocystidia. This is in contrast to Collection 12-08-17/04 and to specimens described from North America and Europe by Gilliam (Mycotaxon 4:1-144, 1976) and Noordeloos (Flora Agaricina Neerlandica 3:146, 1995). It is possible that these basidiomata were overmature and their cheilocystidia had disintegrated.

Photo: D. Malloch (12-08-17/04, 30-06-19/05).