Friday, March 25, 2011

Fossombronia caespitiformis, ventured out of the water

Today I will speak of a very primitive plant belonging to the group of the Hepatics, the Fossombronia caespitiformis. Millions of years ago his aquatic ancestor, an alga, dared to peek into the world colonized land and rocks washed by the fresh water of any lake, river, stream or pond temporary. Gradually became accustomed to short periods of drought with little adaptive mutations that allow it to survive today dehydrated for most of the year. Such is the degree of dehydration in the long summer months virtually unseen. With the first rains of autumn, its leaves like lettuce tiny rehydrate, expand, turn green again and restart their life cycle accumulating nutrients, water and energy through photosynthesis. Early in the winter develops its fruiting bodies, sporophyte, as black balls full of spores at the extremity of long transparent thallus, in an attempt to maximize in order to better and further disperse the spores to colonize new territories.

Fossombronia caespitiformis in February on a limestone facing to the northwest, growing like a green and white carpet cover of fruiting bodies at different stages of maturation.

Fossombronia caespitiformis with vigorous mature sporophytes in early February to embark on the dispersal of spores.

Sporophytes change color as they mature. At first have a deep black color, then they acquire a brown hue increasingly clear until the spores are mature, the fruiting body is torn apart explosively throwing as far as possible the spores.

Details of sporophytes at different stages of maturation. Double clicking on the picture to enlarge You can see the tiny brown spores that have been attached to the torn membrane of fruiting bodies and also the transparent petals.

Photomicrograph at 40 magnification of a sporophyte Fossombronia caespitiformis with measures in microns.

Photomicrograph of the previous sporophyte at the precise moment to tear the bag of fruiting body and disperse the spores. (Double click on the photo to enlarge)

 Fossombronia caespitiformis spores photographed at 400 magnification. Bear a strong resemblance to sea urchins. Its measures to identify with certainty the species.

Saturday, March 19, 2011

It loves the sun and wears wool coat

The fern Cosentinia vellea is a heliophilous and thermophilic  species that together to Notholaena marantae and some Cheilanthes are adapted to live in full sun, making it an exception in the world of ferns. Belongs to the family of Hemionitidaceae and may have a diploid chromosome number of 58 chromosomes (2n = 58, n = 29), Cosentinia vellea subsp. bivalens or have its genome duplicated by apomeiosis, ie autotetraploid, with 116 chromosomes (2n = 116, n = 58), Cosentinia vellea subsp. vellea. Since the phenotype of both subspecies is virtually identical to distinguish them it must done a chromosome count or measure the size of the spores, somewhat smaller in the diploid subspecies.

Vigorous Cosentinia vellea at early May, living in full sun with scorching heat and blinding glare. Is rooted between volcanic stones that hold the ashes of the volcano Teneguía south of the Canary island of La Palma. I was surprised by his good looks against all logic, as at that time I believe it had a temperature above 40 º C. However their fronds were well spread and turgid, unequivocal proof of its excellent hydration. Kneeling on the ash making photos I discovered his secret. If you doing double click on image to enlarge you will note that the ash where rooted Cosentinia is very humid. On the left are even small hepatics and a little moss, something amazing with the torrid heat and the intense drought of the semidesertic southern of Isla Bonita.

When I returned to the car,  I understood the mystery of the moisture that allows the small fern lives very comfortable. The slopes of the volcano Teneguía leading down to the sea are covered with vines grown intelligently by exploiting the same strategy as Cosentinia, the porosity of the lava and volcanic ash, like sponges that absorb moisture from the sea breeze every morning rises from the Atlantic Ocean, soak the surface of the lava and, thanks to its porosity, the sweet water coming from the sea seeps into the deep underground, where have its roots the Cosentinia and the vines. Even if they spend months without rain these plants do not suffer from thirst and remain lush throughout the long summer canary. It is the same phenomenon of horizontal rain in laurel forests, replacing the tops of the trees by the volcanic lava, as in both cases the sea breeze condenses the moisture on the leaves in the forests and on the lava in semi-desert coastal areas, leaving thousands of tons of sweet water, without need of normal rain.

Other beautiful copies on the slopes of the volcano Teneguía. In the Canary Islands it belong to the diploid subspecies, Cosentinia vellea subsp. bivalens. In the same habitat, lives another hairy fern, Notholaena marantae, that in Canary islands is the subcordata subspecies, which uses the same strategy as Cosentinia, including the hairs that protect them from the sun's rays and dehydration.

Here we see the two sun-loving ferns that wear wool coat. To the left there is a Cosentinia vellea with white wool coat and to the right a Notholaena marantae subsp. subcordata with brown-orange wool coat. (Double click on the photo to enlarge)

In a climate quite different from the canary, but using similar strategies, here we see a copy of Cosentinia vellea growing between the stones of a terrace facing south in the Valley of Soller on the island of Mallorca. In the Mediterranean islands, not having the contribution of moisture from the sea breeze, during the summer the hairy ferns enter in aestivation, dehydrate, shrink and wrap their fronds, takes on the appearance of a cotton ball and wait patiently to arrive the first rains of autumn, so that within 24 hours their fronds out the summer lethargy, rehydrated, leafing, expand, unwind and re-look the same a few months before, as if nothing had happened.

Frond of Cosentinia vellea covered by villi that allows to see the green surface of the pinnae. The fronds of Cosentinia have the petiole much shorter than the blade, which is bipinnate, oblong-lanceolate, with pinnules ovate to suborbicular, entire or deeply lobed in the lobes rounded and covered on both sides with woolly hairs multicellular, in a principle whitish and when aging become ferruginous.

Dense white hairs on the underside of the same previous frond that covers even the rachis, like a wool coat.

The sori are developed under the hairiness on the underside of the fronds. Enlarging the picture you can see the mature sporangia as black balls that are about to disperse the spores.

Cosentinia vellea oversized sporangium already deployed after the dispersal of spores. You see some spores that have been retained within the transparent bag.

Spores with beautiful intense dark red color. In this case do not exceed 60 microns and belong to bivalens subspecies.

Cosentinia vellea spores germinate very easily if grown in a lunchbox. In this image you can see several sporophytes of Cosentinia vellea, showing the typical villi of the species.

Sunday, March 13, 2011

Davallia canariensis, the Macaronesian rhizomatous fern

It is a fern lover of light, mild temperatures and frost-free rather dry acid soil. Not support the shade or excessive moisture. Its rhizomes succulent full of water and nutrients help to withstand long periods of drought. I like living on rocks covered with moss and lichens and also as an epiphyte, especially oaks, holm oaks, cork oaks and laurel trees, as garoés, barbusanos, Viñátigo and laurels. Its adaptability also allows clear walls and colonize faial-heath. It ranges Galicia, Asturias, northern Portugal, Cadiz, Madeira and the Canary Islands. Belongs to the family of Davalliaceae and chromosome is 2n = 80. 

Several copies of Davallia canariensis growing in full sun among the stones of a wall of the Villa de Mazo on the island of La Palma. 

In Andalusia, Davallia canariensis is protected by law and the cork corkscrews respect it when found growing as an epiphyte on the cork. The image has its roots tucked between the ridges of cork. Photo taken in the Natural Park of Los Alcornocales in the Cadiz province near the town of Jimena de la Frontera. 

Davallia canariensis group on a wall of volcanic rock of Los Llanos in the island of La Palma. Are several fronds of endemic Polypodium cambricum ssp. macaronesicum. 

Davallia canariensis growing as an epiphyte on a Canary Island date palm, Phoenix canariensis, in the municipality of Barlovento north of the island of La Palma.

Davallia canariensis growing as an epiphyte on a high branch of Garoe, Til or Arbol-fuente, Ocotea foetens, in the lush Bosque de Los Tiles of the Island of La Palma.

This fern also lives in the forest clearings of faial-brezal, like the photo was taken in the town of Los Llanos de Aridane. 

Young Davallia canariensis with rhizome rooted in the moss on a rock of Monte Poiso Madeira Island. The rhizome of this fern grows on the substrate surface always, never shed, because moisture does not support. He needs to touch the air and light. Can measure up to 2 cm in diameter. From the bottom, which is in contact with the ground, sprouting roots that set the rhizome, which is growing and branching out so that it can form a small colony with multiple shoots, all from a single individual.

Details of previous rhizome paleas covered up to 12 mm long, lanceolate, glossy, hyaline and ciliate margin. As it grows and branches to form buds sprout fronds that can reach 50 cm in length, with the petiole as long as the blade, red-brown, paleae covered, darker at the base. The petiole is seen in the picture is green because it belongs to a frond still tender. It will darken as time passes. 

Davallia canariensis fronds with 3-4 pinnate blade, subdeltoid, glabrous, with the last order segments lanceolate or ovate-oblong, dark green, lighter in the tender fronds. 

Davallia canariensis sori, apical submarginal, at the end of the nerves, with cup-shaped indusium.

Sporangium of Davallia canariensis now empty after the dispersal of spores. .

 A long sporangiophore sporangium of Davallia canariensis, which serves as the umbilical cord. It consists of several tubular cells and binds the sporangium to the pinnules, which supplies water and nutrients the sporangiophore sporangium takes the ring, which has a function similar to the mammalian placenta and nourish the spores while growing inside the bag of the sporangium. 

Davallia canariensis spores oblong-reniform, hyaline, large, a beautiful lemon-yellow color.

Sunday, March 6, 2011

Phyllitis scolopendrium, deer tongue

Deer's tongue, Phyllitis scolopendrium synonymous with Asplenium scolopendrium owes its popular name to the shape of their fronds that look like long, narrow tongue of the deer. Its scientific name is composed of a Greek word "Phyllitis" of phyllon, meaning leaf, by its  simple and not pinnate fronds and a Latin word "scolopendrium" which refers to the shape of its fronds centipede, which tend to be similar to undulations of the body segments of the worm. Belongs to the great family of the Aspleniaceae. Its chromosome number is diploid with 2n = 72, n = 36. 

Copy of deer tongue grown in the Botanical Garden of Soller on the island of Mallorca. On this island Phyllitis scolopendrium fern is extremely low. The mother's copy of the photo, from which spores were obtained for culture, lives in a deep ditch in a vertical cave in Majorca called "Sa Cova des cero" (The Deer Cave) that is in the Serra de Na Burguesa. To access the ferns should be climbing down with ropes. Only under these conditions of humidity and permanent shadow survives the hot and dry summers of Mallorca. 

Unlike the exemplary Mallorca, this vigorous Phyllitis scolopendrium lives in broad daylight in a clearing in a laurel forest of the island of Faial in the Azores Archipelago. These Atlantic islands enjoy a warm and humid climate throughout the year thanks to a constant supply of moisture from the horizontal rain, typical of the Macaronesia. Particularly striking is the mark of sori in the face of the fronds, which gives them a segmented or striatum. 

Two other individuals on a slope of the volcano crater called Caldeira do Faial in the Azores. To the left are several sheets of the Azorean endemism Hedera azorica and right down a few fronds of invasive alien Deparia petersenii.
The Phyllitis scolopendrium live in Europe, the Mediterranean, the Azores and Madeira. The farther south than its presence is rare. Their preferred habitat is forests, caverns, caves, ravines, gullies and shady and cool walls with constant humidity throughout the year. 

One of the characteristics of the Phyllitis scolopendrium the base cordate with rounded divaricated auricula and petiole no shorter than the lamina, which is lanceolate in adult and oblong-lanceolate in young copies and can reach up to 60 cms. The base with rounded and not divaricated auricula distinguish it from the Phyllitis sagittata, which in the adult specimens usually have acute and divaricated. .

Underside of a frond with large mature sori arranged parallel to each side of midrib of the blade. 

Detail of linear, parallel to each other and unequal sori that can reach up to 3 cm. Indusium entire margin in the photo is not because it has been opened and the sporangia are deployed, towering above the indusium.

Sporangium of Phyllitis scolopendrium already deployed with the empty bag after the dispersal of spores.

Small spores deer tongue. Its size is generally not exceed 33 microns, which indicates a diploid ferns.

Tiny sporophytes of Phyllitis scolopendrium with his first frond, which has sprung from a fertilized oosphere of a gametophyte. 

Luxuriant population of Phyllitis scolopendrium gametophytes after mass germination of spores dispersed sporangia of an old copy which is a few meters above. Picture taken at Caldeira do Faial in the Azores. They are some sporophytes with fronds at different stages of growth.