Red-orange coloration extends through the inner forward half of the forewing, the hindwing bases, and a small central patch subtended by black.

In the early 1900s, the isolated dune habitat in the Sacramento-San Joaquin River Delta began to experience a dramatic change as human development expanded.

Gypsum dust built up on the butterfly’s food plants, harming its larvae, which were already vulnerable due to the deficient population levels of the species.

[2] According to preliminary research, the Apodemia mormo langei exposed to dust lived a three-day shorter lifespan than those that weren’t.

These difficulties hinder the evaluation of how dust exposure affects various life stages, particularly how it can influence how larvae eat contaminated plants.

Although the subspecies are geographically isolated at the Antioch Dunes, genetic studies suggest it shares significant similarities with other populations within the Apodemia mormo species complex across California.

Traits once believed to be exclusive to Apodemia mormo langei have been observed in other populations, prompting ongoing discussions regarding its classification as an Evolutionarily Significant Unit (ESU).

[3] As a result of these genetic research findings, there is an ongoing debate among conservationists about the optimal management strategy for the species.

All the life stages of Lange's metalmark butterflies are found close to the larval food plant, buckwheat (Eriogonum nudum ssp.