This Humming Bird Hawk moth is held fast by its proboscis stuck in an evening primrose flower (Oenothera rosea) . The moth will die. The various species of evening primrose have all been introduced from the American continent and the insects of Europe which pollinate them are not adapted to these flowers. I would imagine that in the Americas there exist long tongued moths which can extract the nectar without getting trapped. This European moth cannot cope. This photo was given me by a friend. He tells me that several more moths were ensnared in the flowers in a similar manner. But how are they trapped? Looking at the flower you can see a long stalk between the flower and the seed capsule. The latter is dark green and has a small leaf or bract at its base. The stalk is about two centimetres long. This stalk is actually a narrow hollow tube and into it is secreted the nectar. The proboscis of the moth is as long as the body. The moth pushes the proboscis into the narrow tube but clearly it gets stuck not far in. The moth would have approached the flower from the front, full frontal, but in its struggles ends up outside the flower suspended by its proboscis. I do not know if there is a structural mechanism such as protruding hairs which traps the creature or whether it is a form of glue derived from drying nectar which is responsible, or whether the proboscis is just too wide for a slightly funnel shaped tube.

The Humming Bird Hawk Moth is a very attractive insect which is common in the summer, hovering in front of many species of flower, its wings a brown blur of movement. It is reminiscent of a humming bird on some tropical flower. Lavender is a great attraction. It overwinters as an adult, hiding itself in crevices in trees and ruins. It lays its eggs on plants of the bedstraw family. The yellow flowered ladies bedstraw (le caille-lait) is a favourite. As with many hawkmoths the caterpillar carries a spur on the back end. In this case the spur is blue with a yellow tip. The caterpillar at about 4.5 cms long with this spur at the rear is therefore impressive. Considerable numbers of adults emerge in the south of the continent and they migrate to the north each year where they may create a second generation. This year many have arrived in the U.K.This phenomenon of flowers trapping insects by their proboscis happens with other species. I have heard of it happening with Vincetoxicum, the swallow-wort otherwise known as le Dompte-Venin.

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