Pennellia

Pennellia is a genus of flowering plants belonging to the family Brassicaceae (also known as the mustard family). These plants are native to western North America, primarily found in the southwestern United States and Mexico.

Pennellia species are typically annual or perennial herbs characterized by their slender, often erect stems and alternate leaves. The leaves can vary in shape and size depending on the species. The flowers are usually small and white or pale yellow, arranged in racemes or panicles. The fruit is a silique, a dry, dehiscent capsule characteristic of the Brassicaceae family, containing numerous seeds.

The genus Pennellia is relatively small compared to other genera within the Brassicaceae. Species identification can sometimes be challenging, requiring careful examination of morphological characteristics like leaf shape, flower structure, and fruit details.

Pennellia plants are often found in arid or semi-arid habitats, including deserts, scrublands, and rocky slopes. They play a role in the local ecosystems as a food source for insects and other herbivores.

The classification and taxonomy of Pennellia have been subject to some revision over time, and ongoing research may lead to further changes in the understanding of the relationships among the different species within the genus.