Morphological, anatomical and cytological research on endemic Lamium L. (Lamiaceae) species distributed in West Anatolia

In this study, morphological, anatomical and cytological investigations on endemic taxa of Lamium L., the type genus of the Lamiaceae, distributed in West-Anatolia, namely Lamium lycium L., Lamium pisidicum R. Mill., Lamium microphyllum Boiss., Lamium cymbalariifolium Boiss., Lamium sandrasicum P.H. Davis, Lamium eriocephalum Bentham subsp. glandulosidens (Hub.-Mor.) R. Mill, Lamium moschatum Miller var. rhodium (Gand.) R. Mill, have been made. Of the examined taxa, L. microphyllum, L. cymbalariifolium, L. sandrasicum, L. eriocephalum subsp. glandulosidens are high-mountain endemics which are located on the limestone screes on the slopes of summits or serpentin gullies near snow line constitute a group of alpine taxa of the genus Lamium distributed in West Anatolia. L. lycium and L. pisidicum take part in high-mountain endemics with their altitudes upper than 1000 m. The endemic taxon which has the least altitude is L. moschatum var. rhodium. All of these endemic taxa constitute a decorative plant group of the genus Lamium with their well-appeared flowers. Of the investigated taxa, L. lycium, L. pisidicum, L. microphyllum, L. cymbalariifolium, L. sandrasicum, L. eriocephalum subsp. glandulosidens are perennial whereas L. moschatum var. rhodium is annual. In point of morphological characteristics, the investigated taxa have a taproot system, a quadrangular stem, simple leaves and verticillate inflorescence. In point of anatomical characteristics, the taxa reflect the general anatomical characteristics of the family. The taxa are of similar anatomical characteristics, however, there are some anatomical differences between the taxa, depending on being annual or perennial, and habitat features of taxon. Annual wood rings in the root xylem of the perennial taxa, L. lycium, L. pisidicum, L. microphyllum, L. cymbalariifolium are evident, whereas they are not evident in the root xylem of the other perennial taxa, L. sandrasicum and L. eriocephalum subsp. glandulosidens. The most outstanding anatomical feature of the taxa is presence of a collenchyma tissue, being different number layered for different taxa, at the corners of the stems. The arrangement and the number of vascular bundles in petioles for the taxa are similar. On the other hand, cell layer numbers in the palisade and spongy parenchyma of bifacial leaves may differ for the taxa. Large prismatical crystals are very common in the seed cross-sections while a number of prismatical and needle shaped crystals can be observed in leaf mesophylls of all the taxa examined. Starch grains are visible in seeds and floral organs as calyx, corolla, pistil, filament while in all the examined taxa, their structure are quite monotonous. Morphological structure of glandular trichomes which are producing essential oil and characteristic of the family has been examined in all the examined taxa in detail and classified into types. In this point of view, L. eriocephalum subsp. glandulosidens and L. moschatum var. rhodium taxa are found richer than the others in point of glandular trichome type and density. Of all the endemic taxa, firstly subjected to chromosome research, the diploid chromosome numbers in the root tip mitosis of L. lycium, L. pisidicum, L. cymbalariifolium, L. moschatum var. rhodium taxa are determined as 2n=18 via seed germinating whereas the haploid chromosome numbers in the polen mother cell meiosis in the anthers of L. sandrasicum taxon are determined as n=9 via fixing flower buds. Seeds of L. microphyllum could not germinated and the haploid chromosome numbers in the polen mother cell meiosis in the anthers could not be observed. The haploid chromosome numbers in the polen mother cell meiosis in the anthers and any cell division in root tip cells of L. eriocephalum subsp. glandulosidens could not be observed. Results are pointed out by photographs, illustrations and tables.Keywords : Anatomy, Lamiaceae, Lamium L., Morphology, Glandular Trichomes, Cytology.