Structure and diversity
The 2010 account described Lymanbensonia stems as initially upright, then spreading or hanging. They retain the ability to continue growing, and older segments remain part of the plant. Branches also develop in the middle portions of the stem. The margins of flattened segments are crenate, and the areoles bear spines, bristles and hairs. [Korotkova et al. 2010, p. 166]
The flowers are usually solitary, radially symmetrical and narrowly bell-shaped to tubular. Their tepals spread mainly at the apex. In the four species discussed in 2010, colours included pink, red, orange and magenta, with white in L. brevispina. Fruit surfaces are smooth and lack spines. [Korotkova et al. 2010, p. 166]
Identifying the species
The comparison covers the diagnostic features of four species in the 2010 key. The fifth, L. choquequiraensis, described in 2020, has a separate nomenclatural note. [Korotkova et al. 2010] [3-WWW]
| Species | Cecha diagnostyczna |
|---|---|
| L. brevispina | White flowers, flower-bearing areoles not deeply embedded in the stem |
| L. crenata | Orange to magenta flowers, shorter than in L. micrantha, without a distinct receptacular tube |
| L. incachacana | Deeply set flower-bearing areoles with dense tufts of hairs and bristles |
| L. micrantha | Flowers 3–4 cm long with a well-developed receptacular tube |
Mountains and the independent origin of epiphytism
The genus includes plants of southern Ecuador, Peru and the Bolivian Andes. It contains epiphytic species and rock-dwelling forms. For L. micrantha, field studies in the Sandia valley document growth on lichen-covered rocks and steep faces at elevations of 2200–3200 m. [Korotkova et al. 2010, Korotkova et al., p. 166. Hoxey, pp. 191–192] [Hoxey 2016, Korotkova et al., p. 166. Hoxey, pp. 191–192]
The earlier placement of these species in Rhipsalis, Lepismium or Pfeiffera reflected similarities in stem features and growth habits. The 2010 analyses distinguished these similarities from evolutionary relationship. Epiphytism in the Lymanbensonia lineage arose independently of epiphytism in many other cacti. The analysis is described in the article on its relationship to Calymmanthium. [Korotkova et al. 2010]