Bulbophyllum pygmaeum
A very small orchid, usually found growing on tree trunks, along with mosses. Leaves are about 5mm long and 3mm wide.
The round yellow-green things are pseudobulbs, and these are linked by rhizomes to form a mat.
The flower is tiny - about 1.5–2mm across, and often does not open, being self-pollinating. It took me weeks of looking at many plants before I found this one with an open flower.
Flowers Dec-Jan.
