Sunday, July 8, 2012

Lysimachia minoricensis, its destination was the extinction

All attempts to reintroduce it in the wild have failed.

Extinction in the nature of Lysimachia minoricensis remains a mystery. All the hypothesis are logic, but they are still assumptions, because none has been established. 

Lysimachia minoricensis in April. This plant is a biennial cycle. During the first year develop numerous leaves and branches, in the second spring bloom well into summer, in August mature seeds and in autumn and winter dispersed the seeds, after which it withers and dies.

One of these assumptions attribute their extinction to the collection by botanists over a century ago, they had the nefarious habit of collecting every one of them a complete personal herbarium. The discovery of a single, small population of this Primulaceae in 1879 by the renowned Menorcan botanist Joan J. Rodriguez i Femenias (1839-1905) in the Barranc de Sa Vall, located on the south coast of Menorca, mobilized many botanists of the time excited by the discovery of this rare endemic and eager to have their own specimen in their collection of dried plants.

Another theory blames a forest fire occurred between 1926 and 1950 that could wipe out all the vegetation of the gorge where the only known population grew.

Lysimachia minoricensis leaves.

A third hypothesis assumes that agriculture and livestock by man since ancient times favored the survival of  Lysimachia keeping "clean" of vegetation its habitat, it seems that does not tolerate competition from other plants nearby. The progressive abandonment of the field grew the weeds choking the Lysimachia. In fact, with different cultivation in botanic gardens have been found to need bright open spaces. However its discoverer wrote that grew in a cool and shady. Cattle grazing does not affect it because the unpleasant odor of its leaves protect it from being devoured. The odor seems to be an adaptation to the browsing of the extinct antelope Myotragus balearicus who lived in Menorca until about 4,000 years. It was responsible for maintaining clear their habitat by feeding on plants that could compete with it. With the arrival of man on the island Myotragus became extinct in a few decades, probably by over-hunting and was replaced by goats, sheep and cows.

 Detail of a sheet beam with beautiful whitish veins standing out against the dark green lamina.

Lower leaf surface above maroon for its rich in anthocyanins. The bottom of purple color shows that the botanist Joan J. Femenías Rodriguez was right in saying that the only copies who he had found living in a dark habitat. The concentration of anthocyanins in the underside of the leaves is intended to maximize the little light reaching plants living in understory and in north-facing rocky habitats. When solar rays fall on the leaves, penetrate their green tissues where the organelles called chloroplasts capture the light energy and conduct the photosynthesis of the nutrients that plant needs. In normal leaves the solar rays, that are not captured by chloroplasts, cross the leaves and they are lost. However, in the leaves of Lysimachia minoricensis these rays that are going to lose found the layer of cells rich in purple anthocyanins on the underside and are reflected as if it were a mirror, so go back to the green tissues of the leaf and chloroplasts the advantage to perform a second photosynthesis. It is an intelligent process of optimization.

Leaf of Lysimachia minoricensis view backlight. Particularly striking is the highest concentration of anthocyanins in the midrib and in secondary veins. These purple  ribs correspond with the white spots of beam of leaves.

The timely collection of Lysimachia minoricensis seeds in 1926 by the renowned Lleida botanist Pius Font i Quer (1888-1964) and later planted in the Botanical Garden of Barcelona prevented disappear forever from the face of the Earth. Its cultivation in Barcelona was a huge success with abundant germination and survival of many plants that bloom and fructified smoothly year after year. During the Spanish Civil War and early postwar years the garden was abandoned to their fate. When political conditions allowed to resume the care of the garden is believed completely extinguished, but miraculously weeding a small population was found under some bushes. The joy of botanists to test their survival were encouraged to send the highest seed to other botanic gardens, so it could not be any more in danger of extinction. Now grown successfully in many Spanish botanical gardens as the Soller Botanical Garden in Mallorca and foreigners such as Brest, Budapest, Coimbra and Copenhagen. Is also known to survive without problems in some private gardens.

Lysimachia minoricensis flowers in May.

Is assumed to be extinct in the wild between 1926, date of seed collection by Pius Font i Quer and 1950, the resumption of visits by botanists to Barranc de Sa Vall after parentheses the Civil War. After nine years looking for it, in 1959 the botanists Pedro Montserrat, Antoni de Bolos and his son Oriol de Bolos found its disappearance in the only known and declared extinct in the wild.

Detail of the flowers that need not to be pollinated to produce viable seeds.

Since it was declared extinct have been many attempts to reintroduce into the wild. There have been all sorts of experiments, some with surprising results. The first attempt was to disperse thousands of seeds in the Barranc de Sa Vall and other nearby ravines with cool, moist habitats supposedly adequate, as the Algendar and Trebaluger with abundant germination and seedling survival until the summer, when they died all watering yet, except for two sites with fresh, loose and deep soil of Barranc d'Algendar, where some plants were able to overcome the first summer and the following year flowered and gave abundant seeds. Encouraged by the success they proceeded to plant these seeds that germinated well, but only in one locality have overcome the first year.

In late June, Lysimachia minoricensis already formed fruit, though still immature. In the image are several mature plants with long infructescences and many young plants that will bloom next spring.

Immature fruits of Lysimachia minoricensis in early summer.

In 1996 an experiment was done with the planting of mycorrhizal adult plants, which established well and grew vigorously, reaching flowering and fruiting in the first year after planting. Its seeds, however, in low numbers and germinated seedlings did not survive the first summer despite watered regularly.

Details of the fruit in the form of capsules containing numerous black seeds 1 mm. A single plant can produce up to 3,300 seeds, with an average of 1,100.

Given the poor results of all attempts at reintroduction into the southern cliffs of the island with calcareous earth which was supposed to be wild, it was decided to plant mature plants grown in pots, from seeds obtained from plants that had been fruitful in previous experiments, in the interior of the island with siliceous earth, theoretically more cool and moist. Plants grew very vigorous with larger leaves, inflorescences long and numerous flowers, no problems beating the summer. However, despite the abundant production of viable seeds, has not yet been found no germination.

In January the fruits of Lysimachia minoricensis already open and scattered the seeds.

 In this picture we can see the fruits open and empty. At the apex of each capsule is between five seven dehiscent teeth, which are separated to allow dispersion of the seeds.

Is Lysimachia minoricensis condemned to live forever in botanical gardens?

Will ever survive and reproduce without problems in nature without man's help?

Was it the small number of individuals which led to the extinction to be diminishing their genetic variability?. And if so, why is shown as beautiful, healthy and vigorous when grown in gardens and dies or does not play when it is reintroduced into the wild?. Why in the Soller Botanical Garden, located on the neighboring island of Mallorca, the Lysimachia minoricensis is so comfortable that behaves almost like a plague with thousands of plants that are born alone and become adults without problems? 

Will the botanical understand someday capricious behavior of this plant seems to hate its island home and instead lives happily in habitats as different which is supposed to be adapted such as the botanical gardens of Brest (France),  Budapest (Hungary) , Coimbra (Portugal) and Copenhagen (Denmark)?

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