Before getting to Taisha’s entry, a brief tech update: the software has been upgraded to the latest version for the weblog. We’re now waiting on a server upgrade, which should address the speed issues.
Today, we have two images of Cedrus brevifolia, or Cyprus cedar (image 1 | image 2). They were uploaded by one of the top contributors to the Botany Photo of the Day Flickr Pool, andreas lambrianides@Flickr. Much appreciated, Andreas!
Cedrus brevifolia is a conifer species endemic to the Troodos Mountains of western Cyprus. Five natural stands of trees occur, with the majority of the individuals occurring in a single stand called Tripylos. In an area of 1.99km2 at Tripylos, over 240000 individuals have been counted. This species grows on igneous formations and occurs in pure stands, particularly at higher elevations, or in mixed stands with Pinus brutia, Quercus alnifolia, and Platanus orientalis.
Cyprus cedar can reaches up to 15-20 meters, with a diameter at breast height of 1-1.2 meters. Older trees tend to be flat-topped. The bark is pale greyish-borwn with fissures. The branches spread to form distinctive horizontal layers, and bear spirally-arranged leaves that spread radially. Upright cylindrical male pollen-cones are borne terminally on short shoots. These are a pale-brown when mature. Female seed-cones are also upright. These take two years to mature to a ripened grey-brown colour, at which point they become ovoid-oblong or barrel-shaped.
Cedrus brevifolia is only one of four species of Cedrus, or the true cedars (though some authorities consider Cedrus brevifolia to be a subspecies or variety of Cedrus libani). This genus has a disjunct distribution between those species around the Mediterranean Sea and the western Himalayas. In a study by Qiao et al. it was hypothesized that Cedrus has a high-latitude Eurasian origin. Fossils dating from the Paleocene to Pleistocene have been found in Russia Far East to western Kazakhstan, then across Europe to the central Sahara; the oldest fossils are found in the north.
With climatic oscillations throughout the Tertiary, there were many opportunities for taxa to disperse and subdivide. Qiao et al. propose that the genus’ present distribution in several isolated regions could have resulted from vicariance of southerly-migrated populations, followed by further fragmentation and dispersal. They also suggest that the ancestors of Mediterranean cedars might have reached southern Europe in the Miocene based on fossil evidence, and that it is very likely Cedrus migrated into North Africa in the late Tertiary. In addition, the authors also suggest that Cedrus likely did not arrive in the Himalayas until after the Miocene. This would have followed the formation of the Tibetan plateau. The biogeographers note that more fossil evidence is needed to determine the site of origin of Cedrus. The molecular clock estimation of Cedrus divergence times for the phylogeny they constructed was based on the earliest recorded fossil wood from the Paleocene, but the time values obtained could be younger than the real divergence times of the group (see: Qiao, C. et al. (2007). Phylogeny and Biogeography of Cedrus (Pinaceae) inferred from sequences of seven paternal chloroplast and maternal mitochondrial DNA regions. Annals of Botany. 100(3):573-580).