R. simmleri Beauverd, Bull. Herb. Boiss. 11.7: 136. 1907.
Reduced to synonymy under R. cereuscula by Barthlott and Taylor Bradleya 13
Info from B&R 1923

• Stems pendent, cylindric, 2 to 3 mm. in diameter, very much branched,
• Branches dichotomous or 3 or 4-verticillate, upper short and somewhat angled, quite unlike
  lower ones;
• Flowers solitary, subterminal;
• Petals white with pink tips, oblong, 6 to 8 mm. long;
• Filaments 5 to 8 mm. long, white, filiform;
• Style exserted, 9 mm. long;
• Stigma-lobes ovate, reflexed, white;
• Ovary obconic, 3 to 3.5 mm. in diameter;
• Fruit white.

Type locality: Costa Rica.
Distribution: Costa Rica.

This species is named for Paul Simmler, chief gardener of the Boissier Collections at Geneva, Switzerland. The plant was introduced in a collection of orchids from Costa Rica and -flowered in cultivation. Dr. Rose saw it when in Geneva in 1912 and obtained a small fragment, but he did not see it in flower.