Luerella Brass 1979

Abstract

The infrageneric systematics of the orchid genus Luerella are surveyed.

Introduction

The large genus Masdevallia was first recognised by Ruíz & Pavón in 1794. Subsequent workers, notably Luer, have extensively revised the genus and recognised several new genera, such as Dracula and Dryadella, which are commonly found in cultivation.

One species, M. pelecaniceps, described by Luer in 1976, and which is also occasionally found in cultivation, is unlike most Masdevallia in several important respects. Three years after its description, Brass erected the new genus Luerella to accommodate this species alone.

Luer himself did not appear to favour this approach, instead erecting a new subgenus, Pelecaniceps, for the species in 1986. In doing so, he did not state why he substitutes a new name rather than conserving the old, perhaps with a new rank. Without delving into the detailed laws, the general thrust of the International Code of Botanical Nomenclature (ICBN) is to conserve earlier names wherever possible. Luer's new name is therefore considered invalid.

Systematics

Kingdom Plantae

Phylum (Division) Spermatophyta

Subphylum (Subdivision) Magnoliophytina (angiosperms)

Class Liliopsida (monocotyledons)

Subclass Liliidae

Order Orchidales

Family Orchidaceae

Subfamily Epidendroideae

Tribe Epidendreae

Subtribe Pleurothallidinae Lindl. 1830

Genus Luerella Brass 1979

Type Species: Masdevallia pelecaniceps (Luer 1976) Brass 1979

Description: Flowers single; sepals thick, rugose, lacking tails; petals callous, subcarinate externally; lip with acute, erect lateral lobes and an excavate base; column terete, with a hooded ventral anther bearing two pollinia. Monotypic.

Discussion: In erecting Pelecaniceps as a new name substituting for Brass' Luerella, Luer does not state why he substitutes a new name rather than conserving the old with a new rank. This approach appears contrary to the requirements of the ICBN to conserve earlier names wherever possible, and is here treated as invalid.

References

Luer, Carlyle A. 1976: Selbyana 3:22

Luer, Carlyle A. 1986: Icones Pleurothallidinarum II – Systematics of Masdevallia. Monographs in Systematic Botany from the Missouri Botanical Garden Vol. 16.

Luer, Carlyle A. 1993: Icones Pleurothallidinarum. Monographs in Systematic Botany from the Missouri Botanical Garden Vol. 46.