1. INTRODUCTION
Closely related to the Lycastes is the Genus Anguloa, commonly referred to as the 'tulip'
or 'cradle' orchids. While very similar to lycastes in their growth and culture, their spectacular flowers are
both distinctive and desirable. Between the individual species of the genus, the form of the flowers is very similar,
although their colour ranges from white, pink, yellow to mottled red/brown. For reasons best known to themselves,
some of their most brilliant colouration is hidden in the interior of the flower, notwithstanding their bright
exteriors. While not showing the finely intricate structures of many orchids, they have a solid character and appeal
of their own. Additionally they have a fascinating mobile lip like our native pterostylis, designed to trip the
pollinating insect (a male bee) against the column to facilitate pollination. If the flower is gently shaken, the
sound of the lip hitting the sepals can be quite clearly heard.
Flower cut open to show mobile lip
Hinged lip closed (top) and open (lower photo)
Anguloas are listed in the literature as naturally growing as either epiphytes (growing on trees) or as terrestrials
(in the ground). Dunsterville (G. C. K. Dunsterville The Anguloas of Venezuela', AOS Bulletin 48: 2 February 1979) notes... "The consensus of general opinions coming our
way seems to be that it is... basically terrestrial. " Naturally growing in the Andean regions of Colombia,
Ecuador, Peru and Venezuela, they occur at comparatively high altitudes - 600 to 2200 metres above sea level, with
some species growing over a wide latitudinal range.
The Genus Anguloa was founded by the Spanish botanists Ruiz and Pavon on the species unifora, in 1794, being amongst some of the very earliest orchids described. They named the genus in honour
of an amateur botanist Don Francisco de Anguloa, the then Director of General Mines in Peru. Williams (B. S. Williams,
Orchid Growers Manual, 1894) notes it is called 'El
Torito' in its native South America, because of the flowers fancied resemblance to a bulls head. The plants remained
largely unknown in European collections until they were rediscovered in their native habitats by the orchid collector
M. Linden during his 1841-43 journey. Linden's collecting trip was in part paid for by two English orchid growers,
a Mr Rucker and the Rev. John Clowes. Two species were subsequently first flowered in their collections in the
1840s, the species being subsequently named in their honour (A. ruckeri and A. clowesii).
Fowlie (J. A. Fowlie, 1970, The Genus Lycaste) believes that both lycaste and anguloa evolved from a common 'anguloid'
ancestor, the genus lycaste evolving into a successful 'modern' genus, leaving the anguloa as a relect over-specialised
form. Within the orchid family, both genera are included in the Vandoideae sub-family, being considered amongst
the most highly evolved orchids in evolutionary terms, both being included in the Lycastinae Sub-tribe in the Dresler
system (Robert L. Dresler, The Orchids. Natural History and Classification). Dresler notes both lycaste and anguloa have 40 2n chromosomes. These two genera have been hybridised
together a number of times to create the artificial intergeneric hybrid 'angulocaste' A number of these have been very successful, especially in the second generation back crossed to
a lycaste.
Angulocaste Olympus 'Glory'
The taxonomy of the genus is somewhat confused. The number of species considered valid by
various botanists ranges from 2 to about 10. While there is a considerable colour range (white, yellow, pink, red/brown),
the actual morphology (form) of the flowers is very similar, the species differentiation often involving only intricate
variations in the lip details. Many botanists agree on at least 3 species - clowesii (yellow coloured flowers), uniflora
(white) and ruckeri (red/brown). Clowesii and ruckeri are sometimes considered
the same species, being just distinctly different colour forms. Most growers will find the nomenclature based on
the three colour groupings adequate for most purposes. Kennedy (George C. Kennedy, "The
Genus Angoloa", 1
Orchid Digest July/August 1976, and ''Further Notes on the Genus Anguloa - Confused Species of the Anguloa ruckeri
Section', 2 Orchid Digest July/August 1978) has
suggested a finer division of the genus, primarily based on the work of the great German botanist Schlechter, as
published in Orchid, 1916, pp. 122-145. This analysis will also be presented for those who may wish to consider
this detail. Schlechter has indicated two white species (uniflora and virginalis) and three yellow (clowesii, cliftoni and dubia). The ruckeri alliance (red/brown mottled
flowers) additionally includes hohenlohi, macroglossa and
goldschmidtiana, with brevilabris being added later. Kennedy, 2 has
published drawings of the flattened lips, which will also be illustrated here. His articles also include a number of excellent colour photographs, which are worth referring to.
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