Hopkins, H.C.F. & Y. Pillon (2020). Virotia azurea (Proteaceae: Macadamieae), a striking new species endemic to New Caledonia and notes on V. francii and V. leptophylla. In English, English and French abstracts. Candollea 75: 89–98.
Virotia azurea H.C. Hopkins & Pillon (Proteaceae), the seventh species in the endemic genus Virotia L.A.S. Johnson & B.G. Briggs from New Caledonia is described and illustrated. A distribution map and preliminary conservation assessment are provided. This new species occurs principally on non-ultramafic substrates in a restricted area of central Grande Terre. It has relatively long narrow leaves, often with distally undulate-sinuate or bluntly toothed margins and a pointed apex, plus blue flowers and laterally flattened, markedly beaked fruits containing seeds with blue to mauve cotyledons. Its characters are compared with those of other species of Virotia and a key to species is provided. A handful of specimens previously identified as Virotia francii (Guillaumin) P.H. Weston & A.R. Mast are determinated mostly as Virotia leptophylla (Guillaumin) L.A.S. Johnson & B.G. Briggs and other species; the former is now confined to ultramafic substrates in southern Grande Terre and the latter is more widespread, principally occurring on non-ultramafic substrates though occasionally found on ultramafic ones in the south of the island as well.