The last meal of an Eocene pollen-feeding fly

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Specialization for hawkmoth and long-proboscid fly pollination in Zaluzianskya section Nycterinia (Scrophulariaceae)

The evolution of pollination systems has been investigated in Zaluzianskya section Nycterinia (Scrophulariaceae), a group characterized by very long-tubed flowers (up to 60 mm) that open either only at night (19 species) or during the day (one species). Field observations of three species: Z. natalensis , Z. elongata and Z. pulvinata , revealed that their flowers are pollinated shortly after dusk by hawkmoths. Further observations showed that Z. microsiphon , the sole species to have flowers that open only during the day, is pollinated exclusively by long-proboscid flies belonging to the family Nemestrinidae. A phylogenetic analysis of Z. sect. Nycterinia based on morphological characters indicates that Z. microsiphon evolved within a clade of night-flowering species. The shift from hawkmoth to long-proboscid fly pollination in Zaluzianskya was probably facilitated because long corolla tubes, white petals and dilute nectar in hawkmoth-pollinated flowers are pre-adaptations for pollination by long-proboscid flies. However, the autapomorphic features of Z. microsiphon , such as zygomorphy, diurnal flower anthesis and lack of scent, can be regarded as adaptations for long-proboscid fly pollination. Breeding system experiments on Z. natalensis and Z. microsiphon revealed the existence of genetic self-incompatibility. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 138 , 17–27.     

中国东北晚侏罗世虻类化石(昆虫纲:双翅目)

本文论述了辽宁西部上侏罗统虻类６个科的化石,包括１新科,１０个新属和１５个新种。其中Ｐａｌａｅｐａｎｇｏｎｉｕｓ ｅｕｐｔｅｒｕｓ ｇｅｎ．ｅｔ ｓｐ．ｎｏｖ．,Ｅｌｐａｎｇｏｎｉｕｓ ｐｌｅｔｕｓ ｇｅｎ,ｅｔ ｓｐ．ｎｏｖ．和Ａｌｌｏｍｙｉａ ｒｕｄｅｒａｌｉｓ ｇｅｎ．ｅｔ ｓｐ．ｎｏｖ．均属于虻科（Ｔａｂａｎｉｄａｅ）;Ｏｒｓｏｂｒａｃｈｙｃｅｒｏｎ ｃｈｉｎｅｎｓｉｓ ｇｅｎ．ｅｔ ｓｐ     

Mixed hummingbird: Long‐proboscid‐fly pollination in ‘ornithophilous’Embothrium coccineum (Proteaceae) along a rainfall gradient in Patagonia,Argentina

Abstract The pollination ecology of eight populations of the tree Embothrium coccineum was studied along a steep rainfall gradient in NW Patagonia, Argentina. The showy red flowers suggest an ornithophilous pollination syndrome and they have been reported to attract hummingbirds in Argentina and hummingbirds and passerines in Chile. At each population, flower visitors were recorded and floral rewards were analysed. We found a highly significant increase in nectar concentration towards the drier end of the gradient, but this change was not related to the turnover of species in the flower‐visitor assemblage of E. coccineum. In addition to the hummingbird Sephanoides sephaniodes (Green‐Backed Firecrown, Trochilidae) which is widespread throughout the temperate forest at this latitude, other species seem to be locally important as pollinators of E. coccineum in some sites in Argentina (e.g. two long‐tongued tanglewing flies (Nemestrinidae) of the genus Trichophthalma). The long‐dated occurrence of tanglewing flies in South America, relative to the more modern hummingbirds, suggests that ornithophily may be a derived character in E. coccineum, the ancestral condition being pollination by Nemestrinidae.