Double leaflet (Ophrys)

By | October 26, 2017

Double leaflet (Ophrys)

Tubers 2, jajowate. The leaves are collected in a rosette at the base of the shoot, above it, usually 1-2, tessellated covering the inflorescence. The inflorescence is usually a few- or multi-flowering, loose. Medium and large flowers, with widely spread leaves. Usually the outer petals are much larger than the lateral inner petals. Lateral inner petals are often threadlike, densely mossy. 3-patch lip, patches differently educated, a central patch, often cut open at the apex, or with a fleshy appendix, usually dark colored, densely, briefly mossy, with characteristic, contrasting drawing. Stamen straight, sometimes with a highly elongated link. Oval birthmark, concave. Rostellum wcięte, both his patches separated. Hooks 2.

Column of the double leaf type (Ophrys) seen from the front (a) and to the side (b)

This genus includes approx 50 species, mainly growing in the Mediterranean, stretching eastward to Iraq and Iran. Only one of them, the double leaf beetle, which also grows in our country, it is found in central Scandinavia and Estonia. Most of the double leaf species are very variable in terms of lip shape and color. They also easily cross each other. About 100 interspecific hybrids. Seems, that some of them may have stabilized, becoming attractive to non-parent plants, insect species. The enormous plasticity and the ease of creating hybrids create problems for taxonomists dealing with these orchids.

Biceps grow preferably on calcareous soils, in the meadows, in loose, luminous canes and thickets.

Species of this kind are the only European orchids pollinated by the so-called. pseudocopulation. It consists in "bringing” an insect by a plant to a state of excitement and "use" it to pollinate the flower. In many cases the size of the lip, in shape and color it imitates females of some insects (Hymenoptera). In others, even the length and arrangement of the hairs on it resemble the hair of female abdomens! The fleshy appendix at the top of the lip of most double leaflets has a stimulating effect on "copulating" males and probably functions as "female reproductive organs". Plants also emit fragrances like pheromones, which affect the sphere of insects. The lip is dark in color and the hairs covering it, may increase its temperature, and thus increase the emission of fragrances and stimulate the activity of males. The waxy covering of the hairs enables the correct positioning of the insect on the flower in a position favorable to "copulation" and pollination. Hair in direct contact with his body may also possibly chemically affect the male. So we are dealing here with a system of complex optical factors, chemical and mechanical, whose purpose is to attract insects.

Our only representative of this kind, two-leaf mousse (Ophrys insec-tifera) is pollinated by male Gotyles (G. fargei i G. mystaceus). After the insect lands on the plant, it makes a few nervous movements, preparing to copulate. At the same time, he hits the bags with his head, pushing them back and revealing the hoods. The sticky headgear sticks easily to the animal's head. After a while, the handles dry up and take position, which makes it easier to stick them to the birthmark. In some double leaf beetles, the lip shape and its drawing “force” the insect to face downwards. In this case, the pollen sticks to the abdomen of the insect.

The Ophrys apifera may have autogamy. In this species it is possible thanks to the appropriate length of the handles. If the pollen is not removed from the rod by the insect within a few days, their handles dry up, bending towards the birthmark and sticking a mass of pollen to it.

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