Asterella palmeri

Asterella palmeri, also known as Palmer's asterella, is a species of liverwort native to southwestern North America that can be found growing between roughly 30° and 40° north latitude. The plant is found in the U.S. state of California as far north as Redding, and in the Mexican state of Baja California as far south as Punta Baja, as well as in the northwestern corner of U.S. state of New Mexico. According to California bryologists William T. Doyle and Raymond E. Stotler, Palmer's asterella is typically found around chaparral, conifers, and in oak woodland in "exposed to lightly shaded summer-dry soil; usually on gentle to steep slopes." This liverwort is usually found below 950 m elevation, but in the southern Sierra Nevada can be found at up to 1250 m above sea level.

The holotype was collected by Dr. Edward Palmer on Guadalupe Island off the Pacific coast of Mexico in 1875. The range of A. palmeri overlaps somewhat with the range of Asterella californica. A. palmeri is morphologically most similar to A. saccata, A. muscicola and the East Asian species A. grollei.