Micropuntia pulchella

A stem cushion and underground store

The plant usually reaches about 20 cm tall. Numerous short branches cluster around a shared axis to form a cushion. Segments are often slender, cylindrical and more flexible than in many grusonias. Tubercle shape and prominence vary. Areoles retain wool, and small, rapidly shed leaves develop on the youngest growth. [Griffith 2002] [Bárcenas 2016]

The enlarged fleshy underground organ is an important species trait. Areoles and glochids on its parts indicate a contribution from structures of shoot character. In an anatomical description, it is therefore useful to call it an underground storage organ with shoot traits. This wording retains the observation on which Griffith based his comparison. [Griffith 2002]

Fruits, spines and segment retention

Small barbs on fruit spines point towards their tips. Griffith contrasted this trait with barbs bent towards the base in the grusonias compared. He also noted retention of terminal segments and the absence of easy rooting in fragments he observed in the field. The description indicates a different regeneration architecture from strongly clonal chollas. [Griffith 2002]

Distribution

The natural range includes the Great Basin, eastern California, Nevada and western Utah. This distribution complements morphological traits in recognising a distinct lineage. Variation in segment structure and armature was formerly described under many species names, now linked to M. pulchella. [Griffith 2002] [2-WWW]

Molecular data and name history

Griffith compared the ITS region of nuclear ribosomal DNA and obtained a distinct cluster of two samples of this taxon. He published the new combination Micropuntia pulchella in the Haseltonia volume dated 2002, which appeared in 2003. In the 2019 plastome analysis, the genus is sister to Grusonia + Cylindropuntia. [Griffith 2002] [Majure et al. 2019] [2-WWW]

Bárcenas's 2016 paper presented a different position, beside Pereskiopsis, based on three plastid markers. Comparing both results shows how reconstruction of relatedness developed and retains information needed by readers using older publications. [Bárcenas 2016] [Majure et al. 2019]