Fruiting body 0.5-1.0 cm tall, 0.75-1.0 mm thick, a simple, erect, strand, only occasionally branched, straight or with a basal bend, equal to tapering to a slightly enlarged apex; upper two-thirds fertile, glabrous, oval in cross-section, cream-buff to pale peach-buff, in age or on drying tawny-brown; sterile lower portion scarcely distinct from fertile area, usually pallid to white, with occasional sparse hairs; context pliant, solid to stuffed, cream-colored, incorporating clumps of algal cells; odor and taste mild.
Spores 6.0-7.5 x 2.0-3.0 µm, oblong-ellipsoid, thin-walled, smooth, inamyloid, with variously sized vacuoles; spore print not seen.
Gregarious, sometimes forming large colonies on algae covered banks or bark-free logs; fruiting from mid to late winter.
Unknown; too small to have any culinary value.
Multiclavula mucida is one of a relatively small number of lichen-forming basidiomycetes, i.e. fungi that incorporate cells of a green alga within their tissues. These cells are found throughout the fruiting body but are concentrated in the cortical region of the sterile base, though not in sufficient numbers to give the fruiting body a greenish tinge. This is among the smallest of California coral fungi. It is recognized by a slender, usually unbranched, cream-buff fruiting body. Macrotyphula juncea is somewhat similar but grows on the leaves of tanbark oak (Lithocarpus densiflora) and redwood (Sequoia sempervirens). While unrelated, species of Mucronella, a genus of tooth fungi, have fruiting bodies that bear a resemblance, but are pendulous not erect.