Probably a larval food plant for the Texas crescent (Anthanassa texana) and maybe other butterflies since most plants in the Acanthaceae are larval food plants. Flowers provide for a number of nectar-seeking insects and hummingbirds.
There are 3 species of Henrya with of native range from Arizona to Central America. The genus Henrya is named for Aimé Constant Fidèle Henry (1801–1875), a German bookseller and member of the German National Academy of Sciences Leopoldina. The species, insularis, is from Latin meaning “of or belonging to an island”.
Mostly in canyons and riparian areas, in Sycamore canyon in Arizona, and south throughout Mexico.
Island Renegade
Henrya insularis
Family: Acanthaceae
Small, evergreen shrub to about 2’ tall, 3’ wide. Yellow flowers in warm weather followed by dehisive capsules
Full sun to moderate shade, moderate water, hardy to around 25°F. Best in a protected spot.
Photo by Efraín Octavio Aguilar Pérez, iNaturalist
Henrya insularis on SEINET
Plants can often appear with or without leaves, usually depending on resources (water). Like many related Acanthaceae, they are often found growing out of cracks in the rocks, photo by rpmundo on iNaturalist
Flower detail, photo by Glenn Ehrenberg, iNaturalist