Scaphyglottis

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Scaphyglottis
Scaphyglottis stellata
Scaphyglottis stellata
Scientific classification
Domain: Eukaryota
Kingdom: Plantae
Division: Magnoliophyta
Class: Liliopsida
Order: Asparagales
Family: Orchidaceae
Subfamily: Epidendroideae
Tribe: Epidendreae
Subtribe: Laeliinae
Genus: Scaphyglottis
Poepp. & Endl. 1836
Type species
Fernandezia graminifolia
Ruiz & Pavón 1798
Species
Synonyms

Scaphyglottis is an orchid genus formed by almost seventy species characterized by the habit of shooting new pseudobulbs both from the apex and from the base of older ones. A great variety of different plant and flower morphologies which have been described as distinct genera through the years are today considered synonyms of Scaphyglottis. Many species are similar and hard to distinguish, while a few are easy to recognize. Scaphyglottis is a genus widespread throughout the tropical New World. Their flowers are usually small and pale dull colored, however, some species have bright red, purple or green flowers. As they usually bloom again, during several years, on the same pseudobulbs they become interesting plants to the orchid enthusiasts and are occasionally found in orchid collections. Further than the hobbyist interest, Scaphyglottis species were used by popular medicine as pain relievers and, in 2007, it was reported that extracts of S. livida, had antinociceptive and anti-inflammatory properties in mice.[1]

Distribution

The sixty nine currently accepted Schaphyglottis species[2] are spread throughout wide area from South of Mexico to South of Bolivia an all Brazil except south region, from sea level to high altitudes on the Andes. They exist in several Caribbean islands, where, usually, are endemic species. The South of Central America, where most of the species occur, can be considered their center of distribution.[3]

Schaphyglottis are epiphytes, occasionally rupicolous, which often form large desorganized colonies, sometimes ascending or pending from the tree branches. They habit both warm and humid forests of low altitudes from the coastal areas and Amazon as, less frequently, dry jungles on the plateaus. Few species are occasionally found in cloud montane forests in the Andes and Costa Rica, then ordinarily in open sunny areas or on the top of the trees.[4]

Description

The size of Schaphyglottis plants is highly variable. There are delicate tiny species that barely surpass a few centimeters to large and robust ones also reaching one meter heigh. All species show elongated narrow pseudobulbs, on the base protected by several ephemeral sheaths which remain for long time after dried. The pseudobulbs grow both superposed from the apexes and occasionally from the bases of older pseudobulbs forming a long chain; they bear up to three apical leaves.[4] The leaves generally are thin and flat, narrow and elongated although some species have almost terete fleshy leaves.

The inflorescence shoots from the extremity of the pseudobulbs and, different from most orchids, which just bloom once each pseudobulb, Scaphyglottis blooms during several years from older ones. As the pseudobulbs are superposed giving the impression of a long stem, and the older ones bloom again the flowers appear to be along this stem and not on the apexes of each pseudobulb as they really are. The inflorescences may be panicles or racemes, bearing one, few or many, clustered or spaced flowers, which open simultaneously or in succession.

Their flowers are small, generally pale white, cream, green, pinkish, but pale, the exception are the flowers of species that belonged to the genus Hexisea, mostly red;[4] the petals and sepals present similar lengths however the petals usually are wider and the labellum the largest floral structure, frequently with its apex reflected, the base attached to the salient column foot forming a chin, often articulated but sometimes fused to it. The anther is terminal and may contain four or six pollinias.

Scaphyglottis can be separated from its closest genera, among which Jacquiniella is the most noted, because the other genera present cauline pseudobulbs covered by alternating leaves and flowers of columns without a foot.[4]

Most of Scaphyglottis species are pollinated by short tongue insects because almost all produce nectar that accumulates in the mentioned chin. The species of red flowers possibly are also pollinated by hummingbirds, birds which have a preference for red flowers.[3]

Taxonomic notes

The genus Scaphyglottis was proposed by Eduard Friedrich Poeppig and Stephan Ladislaus Endlicher,[5] in 1835. In 1960 Robert Louis Dressler designated Fernandezia graminifolia as its type species, which became Scaphyglottis graminifolia.[6] Scaphyglottis comes from the Greek skaphe, hollow, and glotta, tongue, a reference to the shape of the labellum of its flowers.[5]

Before the current definition of Scaphyglottis, the genus was uncertain for a long time.[7] There is a large group of species clearly belonging to this genus, besides others that where occasionally classified under the genera Tetragamestus, Leaoa and Hexadesmia which were subordinated to Scaphyglottis decades ago, however, many species still were classified under the genera Hexisea and Platiglottys until recently. Every group of species of each one of these genera show some morphological particularities and not always are easily identified as Scaphyglottis species. In 1993, a revision of Scaphyglottis was published and, although the genera submitted to it after this date were not treated on this paper, it is very useful to elucidate the majority of the similar species that form this genus.[7] However, as this paper is not readily available and no comprehensive book has ever been published, the majority of the core species of Scaphyglottis remains not easy to identify to the lay person. This happens both because there is no bibliography and because there are many similar species some spread by wide areas and highly variable with many intermediate morphologies and also endemic variations that have been described as distinct species.

In 2004, other genera were subordinated to Scaphyglottis to fulfill the current phylogenetic concepts.[8] The differences which motivated the description of these genera, today its synonyms, are the following:

Hexadesmia: Is a genus that subordinated twenty seven names, among them fifteen good species. It was described by Adolphe Théodore de Brongniart,[9] in 1842. It was formed by species different from Scaphyglottis because its flowers have six pollinia instead of four. As all these species show in a basal placement on Scaphyglottis clade, it is supposed that this is the ancestral condition of this genus.[3]. Several taxonomists subordinated species to Hexadesmia, among them Schlechter and Reichenbach.

Leaoa: in 1922 Rudolf Schlechter and Paulo de Campos Porto [10] described this small genus for one species that so far was called Hexadesmia monophylla, which presents a very long solitary inflorescence, again with six pollinia, instead of short multi fascicles with several flowers. More species were added to this genus by Leslie Andrew Garay, in 1955,[11] and by Brieger,, in 1976,[12] raising to three the number of species classified under this genus.

Tetragamestus: was described in 1854, by Heinrich Gustav Reichenbach,[13] to Tetragamestus modestus. Four were the species attributed to this genus, the last by Schlechter em 1818.[14] The plants of this group have flowers with a labellum that has a chin les salient than the ones submitted to the other genera. The most noted species was the type species, Tetragamestus modestus, A name that causes confusion with Reichenbachanthus modestus, as both had the same name and are both Scaphyglottis now. The later is now called Scaphyglottis brasiliensis. Tetragamestus still is widely used by enthusiasts who ignore the unification of this genus with Scaphyglottis.[15]

References

  1. Déciga-Campos, M. et al. (2007) Antinociceptive and anti-inflammatory effects of compounds isolated from Scaphyglottis livida and Maxillaria densa in J. Ethnopharmacol 114:161-8.
  2. R. Govaerts, M.A. Campacci (Brazil, 2005), D. Holland Baptista (Brazil, 2005), P.Cribb (K, 2003), Alex George (K, 2003), K.Kreuz (2004, Europe), J.Wood (K, 2003, Europe) (accessed March 2009). World Checklist of Orchidaceae. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet.
  3. 3.0 3.1 3.2 Robert Dressler (2001). Scaphyglottis in A. M. Pridgeon, P. J. Cribb, M. W. Chase, and F. N. Rasmussen eds., Genera Orchidacearum vol. 4: 310-3. Oxford University Press, Oxford, UK ISBN 0198507127.
  4. 4.0 4.1 4.2 4.3 Hoehne, Frederico Carlos (1940). Orchidaceae - introduction in Flora Brasílica vol. 12-1. São Paulo.
  5. 5.0 5.1 Poeppig, Eduardus and Endlich, Stephano (1835). Scaphyglottis in Nova genera ac species plantarum, quas in regno Chilensi Peruviano et in terra Amazonica, (Leipzig) F. Hofmeister (Editor), 1835-45. 1: 58.
  6. Robert Louis Dressler (1994). Proposal to conserve Scaphyglottis against Hexisea (Orchidaceae) in Taxon 43: 665-6.
  7. 7.0 7.1 Adams, Bryan Roger (1993). A taxonomic revision of the genus Scaphyglottis (Orchidaceae - Epidendroideae). Southern University at Carbondale, IL.
  8. Dressler, Robert Louis, Whitten and N.H. Williams (2004). Phylogenetic relationships of Scaphyglottis and related genera (Laeliinae: Orchidaceae) based on nrDNA ITS sequence data in Brittonia 56: 58–66.
  9. Brongniart, Adolphe Théodore de (1842). Hexadesmia in Annales des Sciences Naturelles; Botanique, sér. 2, 17: 45.
  10. Schlechter, Rudolf and Porto, Paulo de Campos (1922). Leaoa in Archivos do Jardim Botânico do Rio de Janeiro 3: 292.
  11. Garay, Leslie Andrew (1955). Leaoa reedii in Archivos do Jardim Botânico do Rio de Janeiro 13: 45.
  12. Brieger, Friedrich Gustav (1976). Leaoa hondurensis in Orchideen 8(29-32): 488
  13. Reichenbach, Heinrich Gustav (1854). Tetragamestus in Bonplandia (Hanover) 2: 21.
  14. Schlechter, Rudolf (1818). Tetragamestus antillanus in Beihefte zum Botanischen Centralblatt 36(2): 400.
  15. Archives of Coordenadoria das Associações de Orquidófilos do Brasil (2008). Orchid shows reports of 2008.