Introduction

This small fern has highly divided leaves, with small involute ultimate segments, and is more reminiscent of species of Argyrochosma than it is of most species of Notholaena. However, it has the chromosome base number (x=30) of Notholaena, farina on its gametophytes, and is well embedded within core Notholaena II based on plastid DNA sequence data (Rothfels et al., 2008). It is a gypsum specialist, endemic to the Chihuahuan Desert of northern Mexico.