Byblis (plant)

B. liniflora

The rainbow plants ( Byblis ) are the only genus in the family of the rainbow plants plants ( Byblidaceae ) and become the Lippenblütlerartigen ( Lamiales ) counted. The first species of the genus, B. liniflora, was described in 1808 by the English botanist Richard Anthony Salisbury, today there are seven known species.

Features

All species are upright growing, weakly woody and not or only slightly branched.

The leaves of all species are terete and are completely covered with fine glandular hairs that secrete a sticky secretion. Small insects are attracted thereof; if they touch it, they die is because they are prevented by the sticky mucus on progress. Can be found either by exhaustion death or suffocate on tenacious secretion, which seeps into their tracheas and clogs them. Unlike the sundew species rainbow plants can neither their music nor their tentacles move but, therefore we speak with them of " passive sticky traps ".

In addition to the glandular hairs still exists a second, embedded in the leaf surface glands guy who is responsible for the actual secretion of digestive enzymes presumably, these sessile glands are five to ten times more frequently than the glandular hairs.

Flowers

The flowers of the plant are available individually at the end of the leaves. You are fünfzählig, purple to pale violet, with B. gigantea and B. filifolia rarely white. B. gigantea and B. lamellata give their pollen only by the sound frequency of an approaching pollinator -free ( vibration pollination / buzz pollination ). Except for the selbstfertile B. liniflora all species are dependent on pollination for seed formation.

Fruit and seeds

The seed capsule is ovoid and zweifächrig, by drying the seed pods they tear on gradually, so that the seeds contained fall to the ground ( Barochorie ). The black seeds are, however, provided roundish in shape and with a honeycomb- like relief, in B. lamellata with fins. The germination of many species is set by bush fires after the dry season in transition, play components in the smoke, the initiating role ( Pyrophilie ).

Dissemination

All rainbow plants are located in Australia. B. gigantea and B. lamellata occur only in South Australia in Greater Perth, the species B. liniflora complex only in northern Australia, where B. liniflora up in the South East of Indonesia and the south of Papua New Guinea is broadcasting. They grow in peat bogs and marshes and prefer sandy soils on its sunny or lightly shaded, seasonally wet sites with temperatures between about 5 and 40 ° C.

Status / risk

All types are available as native plants in Australia under general protection. They stood up to 2000 in Appendix II of CITES; at the request of Australia's protection was lifted. Currently, the trade is not regulated, but limited only to lovers because of the sensitivity of plants. Most of the plants traded today comes from captive bred, but only the one-year B. filifolia and B. liniflora are usually offered, and occasionally B. lamellata, other types must come from seeds, which are often taken from nature, are drawn. The Western Australian species B. gigantea and B. lamellata are threatened by population pressure of the Perth metropolitan area, in particular the draining of wetlands for agricultural recovery Nutzlands. Byblis gigantea is on the red list of the International Union for Conservation of Nature and Natural Resources and is considered critically endangered.

Karnivor or präkarnivor

The status of the species as carnivorous has been repeatedly questioned. On the natural sites also living bugs of the genus Setocoris were observed on all species that lived on the clutches of the plant. Therefore, it was believed that, similarly to the plant bugs, nutrients their excrements are absorbed by the plants either through the foliage or the soil. Even an " indirect" means of digestion chitinaseproduzierender fungi was discussed. Only in 2005 was achieved by tests on Byblis filifolia evidence of digestion of prey by enzymes excreted from the seated glands of the plant, and shortly afterwards was also a proof of B. liniflora.

System

Molecular genetic studies have confirmed the rainbow plants as part of the Lippenblütlerartigen ( Lamiales ); their sister group within the order is uncertain, come into consideration the Martyniaceae, Lentibulariaceae and the Gesneriaceae.

At times, the rainbow plant plants were also assigned to the bugs plants ( Roridula ), but these were now in their own family, the bugs plants plants ( Roridulaceae ) found.

Traditionally, the genus was divided into only two types, namely B. gigantea and B. liniflora. Especially through the work of the Australian botanist Allen Lowrie and John Godfrey Conran more species have been described since the 1980s. Currently, seven species are known, they can be divided into two complexes, the B. liniflora complex and the Byblis gigantea complex.

Species

B. liniflora complex

The five species of this complex, B. liniflora, Byblis rorida, Byblis filifolia, Byblis aquatica and guehoi Byblis are annual herbaceous plants that achieve a growth rate of 15 to 60 ( 100) centimeters and a maximum blade length of 4-15 centimeters. The types are located just a few months from seedling to flowering and survive the dry season as seeds. The original haploid chromosome number of B. liniflora complex is x = 8, the diploid number is 2n = 16; for the tetraploid species B. liniflora and Byblis guehoi it's according to 2n = 32.

Byblis gigantea complex

The Byblis gigantea complex contains two species: B. lamellata and Byblis gigantea. There are perennial subshrubs, reach stature heights of up to 45 or 70 centimeters. These plants survive dry periods by an underground rhizome, from which they then drive out again. Its leaves are up to 20 centimeters long. Basic number of Byblis gigantea complex is x = 9, the diploid chromosome number of the two types is in accordance with 2n = 18

Paleobotany

In 2004, a single fossil seed from the Middle Eocene was found in South Australia; a comparison with today's Byblis species demonstrated the close relationship of the plant with the B. liniflora complex. The "plant" was, as is classified only as a seed known as Parataxon, so as a temporary kind in the rainbow plant growths.

Etymology

The scientific name refers to a figure of Greek mythology, from Ovid in his Metamorphoses reported ( IX, v. 454-664 ): Byblis, granddaughter of Apollo, hopelessly in love with her ​​twin brother Caunus, dissolves, rejected by him, in infinite many, shimmering in the sunshine tears and eventually turned into a source. The fine, secreted by the leaves of plants droplets remember the tears.

The German name goes back to the shiny secretions, in which the light is refracted to different degrees depending on the color and so causes the eponymous rainbow effect.

Evidence

  • Allen Lowrie: Carnivorous Plants of Australia - Vol 3, Nedlands, Western Australia, 1998
  • Allen Lowrie, John G. Conran: A Taxonomic Revision Of The Genus Byblis ( Byblidaceae ) In Northern Australia, Nuytsia 12 ( 1) :59 -74, 1998
  • Allen Lowrie, John G. Conran, Jessica Moyle - Croft: A Revision Of Byblis ( Byblidaceae ) in South - Western Australia, Nuytsia 15 ( 1) :11- 19, 2002
  • John G. Conran: The embryology and relationships of the Byblidaceae. In: Australian Syst. Bot Melbourne 9.1996, 243-254. ISSN 1030-1887
  • John G. Conran, R. Carolin: Byblidaceae. In: Flowering plants, dicotyledons: Lamiales (except Acanthaceae including Avicenniaceae ). In: J. W. Kadereit (ed.): The Families and Genera of Vascular Plants, Vol 7, Berlin / London 2004, pp. 45-49, ISBN 3-540-40593-3
Byblis liniflora Asterids Ernest Friedrich Gilg Karel Domin Byblis lamellata Kaunos (mythology) Nuytsia (journal)
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