Microdon is a genus of flowering plants in the family Scrophulariaceae. It includes seven species of subshrubs or shrubs native to the Cape Provinces of South Africa.

Microdon dubius, synonymously known as Agathelpis adunca, Agathelpis angustifolia, Agathelpis brevifolia, Agathelpis dubia, Agathelpis mucronata, Eranthemum angustatum, Eranthemum angustifolium, Selago angustifolia or Selago dubia and commonly known as Cats’ Tail or Snake Catstailbush, is a South African endemic perennial found in the Northern Cape and Western Cape provinces. It grows into a densely leafy shrublet with wand-like, hairy stems up to 60cm. The leaves are oblong-linear. From August to January it bears long spikes of yellow flowers, often with maroon to brown petals. These are sharply scented at night, suggesting moth pollination.