Cookeina colensoi (Cup fungi)
Species: C. colensoi
Binominal name: Cookeina colensoi
Synonyms: Boedijnopeziza colensoi, Peziza colensoi, Sarcoscypha colensoi
Common name: Cup fungi
All the Cookeina species have a deep, cup-shaped to funnel-shaped fruiting bodies (apothecia). The inner spore-bearing surface of the apothecium, the hymenium, is coloured pale cream to red depending on the species. The excipulum, the tissue making up the walls of the apothecium, is thin and flexible.
Cookeina colensoi is found in New Zealand, Australia, West Indies and Africa. In New Zealand it is usually found in the late autumn or winter on decorticated wood. It has a shallow, pale-yellow cup (apothecia) that is 1-1.5 cm. in diameter and about 5 mm. deep and is attached to a wood substrate by a short stalk.
When mature the apothecia become filled with water, the asci (sexual spore-bearing cell) absorb some of that water and develop a turgor pressure, a hydrostatic pressure within the ascus which put pressure on the tip of the ascus, held in place by the rigid ascus wall. As the water level in the cup reduces due to evaporation, the asci tips dry out, resulting in a negative vapour pressure that ultimately results in the thin tissue at the wall of the apex (operculum) breaking outward, releasing the spores.