Pollination of Habenaria tridactylites (Orchidaceae: Orchidinae) on the Canary Islands
Fecha
2019
Tipo
artículo original
Autores
Claessens, Jean
Bacallado, Juan José
Bogarín Chaves, Diego Gerardo
Dedroog, Liliane
Heijungs, Reinout
Langelaan, Rob
van Nieukerken, Erik J.
van den Berg, Kees
Gravendeel, Barbara
Título de la revista
ISSN de la revista
Título del volumen
Editor
Resumen
We investigated the pollination of Habenaria tridactylites, an endemic orchid of the
Canary Islands. The entirely green, widely open flowers have a long spur containing
nectar. We carried out fieldwork, a molecular clock analysis, herbarium surveys, identified
pollinators by both morphology and DNA barcoding, and measured the length
of floral spurs and insect tongues using a combination of traditional and innovative
micro-CT scanning methods to 1) determine the pollinator of this orchid and 2)
investigate correlations between local mean spur length and age, altitude and longitude
of the island. Habenaria tridactylites was found to be pollinated on Tenerife by both
small and intermediate sized moth species with variable tongue lengths and mostly
belonging to Geometridae and to a lesser extent Crambidae, Erebidae, Noctuidae and
Tortricidae. Of the sixteen moth species identified, nine are endemic to the Canary
Islands or Macaronesia. The different local populations of H. tridactylites on the islands
of Gran Canaria, El Hierro, La Gomera, La Palma and Tenerife with different ages and
distances from mainland Africa, did not show a significant correlation of mean spur
length and altitude, but did show a significant and positive linear correlation with longitude
and the geological age of the island. The latter is congruent with the evolutionary
arms race theory first proposed by Darwin, suggesting that flowers gradually evolve
longer spurs and pollinators longer tongues.
Descripción
Palabras clave
Endemics, Free spur space (FSS), Lepidoptera, Orchids, Spur, Tenerife