Ilex anomala

In the lush, verdant ecosystems of the Hawaiian Islands grows a unique and lesser-known member of the holly family—Ilex anomala, commonly known as Hawaiian holly. This evergreen tree is not only notable for its distinct botanical features, but also as a symbol of the extraordinary evolutionary paths of island flora.As part of the genus Ilex, which includes more than 400 species worldwide, Ilex anomala is one of the rare few that evolved independently on isolated islands. Unlike many of its cousins from temperate zones, this species is adapted to the wet, tropical climates of Hawaii.

Ilex anomala is endemic to Hawaii, meaning it is found nowhere else in the world. It occurs on all of the main Hawaiian Islands, from Kauaʻi to Hawaiʻi (Big Island), thriving in a range of environments—from wet montane forests to cloud forests, typically between 400 to 2,000 meters in elevation.

It is commonly found growing alongside koa and other native trees in mixed mesic to wet forests. These ecosystems are often shrouded in mist and nourished by consistent rainfall, creating the perfect microclimate for this moisture-loving species.Ilex anomala is an evergreen tree or large shrub that can reach up to 10–15 meters in height, though it is often smaller depending on habitat conditions. It has a straight trunk, dense crown, and smooth, grayish bark.The leaves are oval to oblong, leathery, and dark green with a glossy finish. Unlike the iconic spiny leaves of many holly species, Hawaiian holly leaves are entire or slightly toothed, with a more subdued, gentle appearance—likely an evolutionary result of having no large herbivores to deter on the islands.