Tuesday, January 4, 2011

Asplenium x orellii, a vegetal mulatto

Asplenium x orellii named after the Majorcan botanist Jeroni Orell Casasnovas (1924-1995) who found in one of his botanical excursions in the mountains of Sóller, but then went registered officially and described to science in 1969 by botanists Lovis & Reichstein, which was dedicated to him, since it was he who had taught this beautiful fern, fruit of crosses between the allotetraploid hybrid Asplenium majoricum and the autotetraploid Asplenium trichomanes ssp. quadrivalens.

Asplenium fontanum ---> X <--- Asplenium petrarchae ssp. bivalens 
                Asplenium majoricum ---> X <--- Asplenium trichomanes ssp. quadrivalens 
                                                                    Asplenium x orelli
Of all the hybrid offspring of Asplenium majoricum perhaps Asplenium x orellii is the most abundant. In its allotetraploid genome chromosomes of three ferns takes different: 25% of Asplenium fontanum, another 25% of Asplenium petrarchae ssp. bivalens and the remaining 50% of Asplenium trichomanes ssp. quadrivalens.

Magnificent specimen of Asplenium x orellii growing on a bed of moss between the stones of a wall patch oriented northwest to 90 meters. Macroscopically it looks like a giant majoricum Asplenium with black spine.

Previous specimen viewed from the side with the details of the erect bearing fronds extended into the light by its strong heliophilia.

Another Asplenium x orellii growing on the northwest slope of Puig den Ramis of Soller Valley.

Asplenium x orellii surrounded by several copies of one parent, the Asplenium majoricum, much smaller and the green stalk, while his son is clearly more robust and its spine is black except apical part of the blade.

Young Asplenium x orellii growing in a rocky crevice of Puig den Ramis accompanied by his parent Asplenium majoricum.

New frond of Asplenium x orellii with typical macroscopic features that define it: generally erect bearing fronds outstretched toward the light, the petiole much shorter than the blade, it lanceolate or linear-lanceolate with lobed pinnae almost identical to those of the parent Asplenium majoricum, decreasing size of the apical and proximal, the most wide with two basal pinnules; rachis black or dark brown like his other parent Asplenium trichomanes ssp. quadrivalens, only green in the distal part of the blade. No trichomes or glandular hairs.

Another typical frond of this hybrid is well appreciated that the green portion of the spine and the apex more or less lobed edge of the pinnae. (Double click on the photo to enlarge)

Vigorous sprouting in late February of the hybrid of the first photo. It looks in detail the transition from black to green rachis and two basal pinnules broader pinnae. (Double click on the photo to enlarge)

Underside of a frond of a vigorous specimen of the first picture with the details of sori inserts near the coast or central nerve of the pinna, except those found within two pinnules small base some of the pinnae larger. The indusium is partially lifted, showing the mature sporangia initiating the dispersal of spores.

Detail of sorus with sporangia already fully deployed after the dispersal of spores. (Double click on the photo to enlarge)

Asplenium x orellii is a sterile hybrid with unviable and aborted spores, since having different chromosomes of three ferns is virtually impossible in meiosis chromosome to form a combination compatible with life. Pictured is a beautiful aborted sporangia with spores inside the transparent bag that serves as the uterus, which could not be dispersed because they are partially decomposed, turned into a sticky mess of dead spores.

Dead and broken spores of Asplenium x orellii, glued together forming a black mess.


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