Floral adaptations to nocturnal moth pollination inDiplomorpha(Thymelaeaceae)

Melampyrum koreanum (Orobanchaceae) was described recently as an endemic species in Korea. This study examined the distribution range, relationship with the host plant, flower developmental pattern, pollinator, pollination mechanism, and seed development of M. koreanum (Orobanchaceae) on the island of Somaemul-do, Korea. M. koreanum is hemiparasitic and a strong candidate for its host plant is Pinus thunbergii, with which it is distributed sympatrically. The flower of M. koreanum represents a typical hawk moth pollination syndrome. Macroglossum pyrrhostictum Butler (Sphingidae, Lepidoptera), a diurnal hawk moth, is the only efficient pollinator. The proboscis length of M. pyrrhostictum and the floral tube length of M. koreanum are well coordinated, and the positions of the anther and stigma of M. koreanum are mechanically conformed to hawk moth pollination. The results suggest that adaptation to the pollinator is the main factor that has affected the evolution of the longer floral tube of M. koreanum compare to other species. Pollinator conservation in the native range of M. koreanum is an important issue for the conservation of endemic plant species, and it is necessary to establish a conservation plan for the host plant, Pinus thunbergii, as well as M. koreanum.

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The trichotomosulcate asparagoids: pollen morphology of Hemerocallidaceae in relation to systematics and pollination biology

Australian Systematic Botany ◽

10.1071/sb13046 ◽

2013 ◽

Vol 26 (6) ◽

pp. 393

Author(s):

Carol A. Furness ◽

John G. Conran ◽

Thomas Gregory ◽

Paula J. Rudall

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Pollen Morphology ◽

Pollination Biology ◽

Molecular Analyses ◽

Moth Pollination ◽

Transmission Electron ◽

Pollen Surface ◽

Scanning Electron

We examined pollen of 19 genera of Hemerocallidaceae by using scanning electron microscopy (SEM), and one genus (Dianella) by using transmission electron microscopy (TEM). Pollen was generally small in size, with a rounded triangular outline when hydrated, and a characteristic three-armed aperture, a distal trichotomosulcus. The pollen surface was finely sculptured and the exine was thin. Microreticulate pollen is a potential synapomorphy for several species of the ‘crown phormioid’ subclade recognised in molecular analyses. Perforate and fossulate pollen supports a relationship between several species of Dianella. Microrugulate pollen is more frequent in the johnsonioids than in the phormioids. Hemerocallis is distinguished by elongated monosulcate pollen, a relatively thick exine with a pronounced reticulate surface, and large globules of attached pollenkitt. We hypothesise that Hemerocallidaceae are ancestrally buzz-pollinated, and their pollen morphology is an adaptation to this pollination type. A reversal to butterfly or moth pollination occurred in Hemerocallis, with associated changes in pollen morphology.

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