Coral Spot
Nectria cinnabarina
The Coral Spot is a widespread ascomycete fungus characterized by its striking cinnabar-red to orange fruiting bodies. It acts as a saprobe on dead wood but can also function as a weak parasite on living deciduous trees, often causing dieback of twigs. The fungus exhibits a distinct alternation of generations between a pale red asexual stage and a darker red, warty sexual stage.
Details
Identification
Cinnabar-red, cushion-shaped fruiting bodies (1-4 mm) on the bark of deciduous wood; asexual stage (Tubercularia vulgaris) is smooth and pale red; sexual stage is dark red, rough, and clustered in warty pustules.
Diet
Feeds saprobically by decomposing lignin and cellulose in dead hardwood or parasitically on weakened plant tissue.
Overwintering
Overwinters as mycelium within the wood or in the form of fruiting bodies (perithecia).
Ecology
Ecological role
Important primary decomposer of dead wood in forest ecosystems; contributes to humus formation and the nutrient cycle.
Natural predators
Various fungivorous insect larvae, mites, and snails.
Competitor species
Other wood-decaying fungi such as Diatrype disciformis.
Ecosystem service
Acceleration of wood decomposition and provision of nutrients for the soil.
Threats
No significant threats known, as the species is highly adaptable and widespread.
Scientific profile
Profile
Distinguishing features
Characteristic is the simultaneous or sequential appearance of pink cushions (anamorph) and red pustules (teleomorph) on hardwood. Microscopically, the ascospores are elliptical, two-celled (uniseptate), and measure approximately 12-20 x 4-6 µm. The conidia of the asexual stage are unicellular, hyaline, and ellipsoid (5-7 x 2 µm).
Habitat
Deciduous mixed forests, parks, gardens, avenues, and hedges; ubiquitously distributed throughout the temperate zone.
Reproduction
Asexual reproduction via conidia (dispersed by wind and rain) and sexual reproduction via ascospores produced in sacs (asci) within the perithecia.
Protection & threats
Main threats
No known threats; the species is very common and widespread.
Conservation measures
No conservation measures required; in forestry contexts, removal of infected branches is recommended to reduce infection pressure.