Habitat and Range
There are at least nine other Coccomyces species in the Pacific Northwest. 1) Coccomyces arbutifolius was described from BC on Arbutus menziesii leaves (apparently living leaves). The leaves are marked by a faint superficial bloom but there is no bleaching or encircling line, and both ascospores and asci are larger. 2) Coccomyces arctostaphyli, recorded from OR, AB, and Europe, is inconspicuous on leaves of Arctostaphylos uva-ursi (kinnikinnick). 3) Coccomyces castanopsidis, found in OR and CA, is up to 0.4cm across with a bright yellow hymenium, and grows on dead bark and wood of Castanopsis (chinquapin) and Quercus chrysolepis (Canyon Live Oak). 4) Coccomyces heterophyllae occurs on twigs of Tsuga heterophylla (Western Hemlock) in the coastal forests of BC and WA in spring and summer. 5) Coccomyces ledi grows on living twigs of Rhododendron groenlandicum (Labrador-tea) and R. tomentosum (northern Labrador-tea), late summer and early fall, and is common in arctic and alpine localities (including BC, OR, MB, NT, NH, Europe, and Asia). 6) Coccomyces leptideus is common on living and recently killed twigs of Vaccinium myrtillus (bilberry), V. vitis-idaea (lingonberry), Rhododendron macrophyllum (Pacific rhododendron), and Gaultheria shallon (salal). Spores are either 4-spored, with spores 60-90 x 4(5) microns, or 8-spored, with spores 60-90 x 3.0-3.5 microns. It grows in summer and fall, in WA, OR, and Europe. Coccomyces gaultheriae is distinguished from C. leptideus by its shorter, broader ascospores 19-22 x 6-6.5 microns. [C. gaultheriae has been recorded from twigs of Gaultheria shallon from BC by Adolf and Oluna Ceska]. 7) Coccomyces parvulus grows on decorticated wood of various conifers in WA and OR. The colonies look like charred wood and the fruitbodies are only 0.03-0.08cm across and round to elongate, up to twice as long as they are wide. 8) Coccomyces pseudotsugae produces black fruitbodies 0.06-0.12cm across on bark of Pseudotsuga menziesii (Douglas-fir) and Abies grandis (Grand Fir), and has been found in BC, WA, and CA, 9) Coccomyces tumidus produces relatively large, fleshy, rugose, dark brown fruitbodies 0.1-0.2cm across, round to elongated, with a dull yellow to yellowish tan spore-bearing surface. They grow on long dead leaves of a variety of hardwood trees especially oak and beech and other plants including salal and Rubus. The fruitbodies are on bleached areas of the leaf, usually surrounded by a black line. Distribution includes WA, OR, MA, ME, NH, NY, VA, NS, ON, and Europe. 10) Coccomyces coronatus of Europe and eastern North America, with which C. dentatus is frequently confused, "has inflated paraphyses, longer asci and ascospores, less regular apothecia, and rarely occurs on leaves of evergreens". (Sherwood). Kroeger(5) reported C. tumidus from salal in Haida Gwaii, BC.on "dead (rarely living) leaves of a wide variety of angiosperms, notably on Fagaceae and Ericaceae, widespread and common, chiefly in warm temperate areas, summer and fall in the northern part of its range, throughout the year in subtropical areas", (Sherwood)