Nectria Cinnabarina

or to give it it's common name, Coral Spot Fungus.

With the weather awful again ahead of Barney I thought I'd look for something for Tiny Tuesday. Sat in the office I could see a glint of orange on the quince bush - I was hoping for lichen - but instead I got something remarkably similar.
This tiny fungus (these fruiting pustules are the sexual, reproductive stage of a two part, or polycyclic, life cycle) are approx 1mm diameter. The fungus is now accepted as being a symbiotic complex of four species - so very similar to, but not, a lichen.
Sadly, whilst beautiful, its not good news for the quince bush - some aggressive pruning will be called for in the spring. Whilst it initially colonises dead twigs and branches (transported by wind or rain) and takes hold in the bark's pores or existing weaknesses, thus being saprophytic in nature,  the fungus will migrate to living tissue (usually via pruning snags or broken branch joints) and live as a (admittedly weak) parasite. The thread like hyphae (the filament growth structure of the fungus - again very like lichens which share a similar construction) of the fungus will then block the plant's xylem (think veins) vessels & prevent the flow of water - causing it to die back, and thus the cycle is complete.