Tuesday, September 25, 2012

Tetraclinis articulata, a treasure from Murcia, relic of Late Miocene

The Strait of Gibraltar separated it from its African sisters.

The Sabina mora, Araar, Cypress of Cartagena, Sandarac, etc ...with scientific name Tetraclinis articulata, is a small conifer of Cupressaceae family with tall of shrub generally, although in highly concessional conditions can reach 16 meters in height and a trunk thickness of 1.2 meters. It is the only species of the genus Tetraclinis.

 
Tiny newborn Tetraclinis articulata  in September 2005. About 9 years ago a young man from Cartagena visited my garden website and he looked for a picture of this Iberian-african endemism beloved by Murcian  botanists, but found none. Then looked at the list of my garden plants and found that there was no copy of this beautiful conifer. Something angry he wrote me an email offering Tetraclinis articulata seeds of Cartagena, because "I want that you have an endemic plant of Murcia in your garden," he said. A few days later I received an envelope with 4 seeds of Araar.

 Of the 4 seeds that the young man sent me (that if one day read this article I want to know that is dedicated in gratitude for their generous gesture) three seedlings germinated in March, of which only one survived. Now with over 7 years of age has become a tree of more than three meters high, which is growing fast and seems very comfortable rooted in the rocky, chalky soil of Mallorca.

The botanist who gave the name knew summarize in two female words the essence of its anatomy. The Latin name of the genus Tetraclinis comes from the union of two Greek words, κλινα and τετρά, meaning four beds, for the four scales concave form of the strobilus off and remember the old couches (triclinium) of Romans. (From κλινη, κλινης = bed comes some actual words of our language, as recline, incline, decline, clinic, clinometer, triclinium, etc. ..). The species name, articulata, refers to the peculiar arrangement of the twigs loose like pieces joined or articulated at their ends. 

"Articulated" twigs of Araar tree.

The current distribution of Araar in the southeast of the Iberian Peninsula (Cartagena Mountains in the province of Murcia), in North Africa (Morocco, Algeria, Tunisia and Melilla) and small places on the island of Malta and the island of Cyprus speaks clearly of its Miocene origin. A curious fact was discovered in 1997 a group of 24 centenarians Tetraclinis articulata in the Doñana National Park, specifically in the Coto del Rey in Hinojos (Huelva), some up to 16 meters in height and a trunk circumference of 2 ' 62 meters, much larger than those of Cartagena. Given its age, its size and the absence of signs of having been planted by man, it follows that they are natural, a vestige of what were great forests of Tetraclinis before intense deforestation at the hands of man.  Tetraclinis articulata in Doñana.

 Cypress of Cartagena 7 months old in March 2006. It shows very well how it are changing the leaves as it grows. The former, who wear the stem, are long pointed needles as any conifer. In each new sprouting are becoming shorter to insignificance in their adult phase, as seen in the photo twigs articulated above. The tree performs photosynthesis directly on green twigs. These two phases in the foliation, with juvenile foliage and adult foliage, are typical in conifers of the Cupressaceae family: Juniperus, Cupressus, Thuia, Chamaecyparis, Platycladus ...

The Mediterranean Sea, a direct descendant of primitive Tethys Sea, almost completely dried about seven million years ago during the Messinian great salinity crisis of Late Miocene which took about a million years, during which the sea water is evaporated and salts were deposited on dry sand, desert valleys becoming lifeless what had once been a rich seabed. The cause of desertification was a sudden climate change that much the Earth cooled and made fresh water to accumulate as ice on Antarctica, covering it with a thick layer of water ice several kilometers thick, which caused a decrease significant rains across the globe and of course also in the Mediterranean and a decrease in sea level of over 100 meters.

 
Same Araar at 4 years old in November 2009.

To coincide with the global cooling there was a sudden movement of the African tectonic plate, which, in its continuous ascent northward from which separated the great southern continent Gondwana, collided violently with the European tectonic plate and as a result of this collision is raised the seabed, forming the Betic-Rif Massif which closed the communication between the Atlantic Ocean and the Mediterranean Sea. The reduced rainfall and cessation water ingress to the Mediterranean ocean engulfed in a gradual drying process by simple evaporation and in a few millennia became a very salty sand desert with some caustic lakes in the lower parts.  Toward these lakes came flocks of pink flamingos from Africa and Asia to feed on small halophilic invertebrates and algae living in its  brackish waters.

Approximate boundaries Betic-Rif Massif during the late Miocene in full Messinian salinity crisis with very salty lakes occupying the lower parts of the seabed of the Mediterranean Basin. The brackish lake size depended on the scant rainfall, reaching to dry completely for several millennia. In the mountaintops rains were more generous than in the deep valleys whose sandy soil was covered by a thick layer of salt.

During this million years what had been mountains became islands and coasts of Europe and Africa came together in a continuum without water than separated. It was then that many plants and animals European, African and Macaronesian could expand their populations and occupy all that vast region. Cypress Cartagena, our Tetraclinis articulata, from its native Africa colonized the mountains of Betic-Rif Massif, settling in warmer mountain slopes facing south.

 Current distribution of known indigenous populations of Tetraclinis articulata. In southeastern Spanish small feral populations exist outside Murcia, especially in Malaga and Alicante, which are products of ancient repopulation.

At the end of the Messinian period about 6 million years the Earth suffered a new climate change with global warming that increased rainfall across the planet, melting much of the Antarctic ice and rising water level of the oceans in more 60 meters. At the same time there was a new tectonic movement and European and African tectonic plates separated and Betic-Rif Massif split in two forming a deep groove, the Strait of Gibraltar, which again allowed the entry of oceanic water into the Mediterranean, forming an impressive waterfall drop of several kilometers and a flow of millions of tons of water per second, which quickly filled the Mediterranean in just about 1000 years.

Same Araar tree of 7 years old  in September 2012 with a height of over three meters. Its affection for the sunlight makes grow it inclined toward the midday sun.

What during the Messinian period had been some mountains surrounded by a brackish desert became current Mediterranean islands, isolated again by seawater. The plants and animals that lived in them were isolated from other populations of the same species, as happened to the conifer Tetraclinis articulata, surviving to the present day as relics of those turbulent prehistoric times.

Tetraclinis articulata male strobili in November. This tree is monoecious with separate male and female flowers on the same plant.

Tetraclinis articulata female flowers on the same copy before.

Detail of a female flower of Tetraclinis articulata.

Combined photography with male and female flowers.

Fruits of Tetraclinis articulata about to mature in August.

Details of previous fruits.

Mature fruits in mid-September. The four scales of the strobilus are opened to release the winged seeds.

Fruits of Tetraclinis articulata with flakes shaped as roman kneelers.

Tiny seeds of Araar tree shaped as winged samara, flying like small helicopters windblown to colonize new territory away from his mother.

The Sabina mora is much appreciated in gardening, though still a rarity in private gardens. May be reproduced by grafting on Thuia and Cupressus. It is grown successfully in all the Spanish Mediterranean botanical gardens. In Murcia have made numerous reforestation to increase its range. It is the national tree of Malta which is called Sandarac gum tree in English and gharghar in Maltese. Its Araar name comes from the Arabic and so is commonly called in North Africa.

Genetic studies have been made of the copies from Murcia and results were compared with the genome of the North African, Maltese and Cypriots trees. Surprisingly no significant differences were found. It follows that the cupressaceae Tetraclinis articulata presents a great homogeneity and genetic stability, despite their different populations carry six long separated million years.



8 comments:

  1. Beautiful article about araar tree... Is it the same araar often smoked in Algeria to cure from tobacco ?

    ReplyDelete
  2. Thanks, Anonymous. I believe it is not. Its savia of conifer is toxic.

    ReplyDelete
  3. Very interesting article , should you need some seeds of Tetraclinis articulata just let me know and I will send you some from my tree .

    ReplyDelete
    Replies
    1. Hello
      Does this offer yet?
      If you could let me have some seeds, I would start a trial with germination.

      Best regards

      jrothkegel@website-sos.de

      Delete
    2. Hello. Anonymous:

      It's better you contact with a website that sells seeds online, like this: http://www.sandemanseeds.com/search.asp

      Best regards.

      Delete
  4. Hello, whereabouts in Mallorca do you have this precious tree?
    Have you since grown more?
    Un saludo,

    ReplyDelete