Further Investigations on Rhizocarpon of North-Eastern Iran: R

Hindawi Publishing Corporation Journal of Mycology Volume 2014, Article ID 528041, 5 pages http://dx.doi.org/10.1155/2014/528041 Research Article Further Investigations on Rhizocarpon of North-Eastern Iran: R. geographicum Mahroo Haji Moniri Department of Biology, Faculty of Sciences, Islamic Azad University, Mashhad Branch, Mashhad 917 56 89 119, Iran Correspondence should be addressed to Mahroo Haji Moniri; h [email protected] Received 15 January 2014; Accepted 7 April 2014; Published 29 April 2014 Academic Editor: Simona Nardoni Copyright © 2014 Mahroo Haji Moniri. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Morphology, anatomy, secondary chemistry, ecology, and distribution of Rhizocarpon geographicum (Rhizocarpaceae, lichenized Ascomycota) in north-eastern Iran are investigated and discussed. 1. Introduction the elevation of the sites ranges from 1340 to 1880 m. Over 537 Rhizocarpon thalli were investigated of which 311 (58%) Iran has an exceptional variety of biomes which has resulted belong to R. geographicum. As a result much new information in an extensive diversity in many organism groups including became available on the species of Rhizocarpon [11–13]. Mor- lichens. The history of lichenological exploration in north- phological and anatomical characteristics of the thalli and eastern Iran is fairly extensive, dating back to the middle fruiting bodies were examined with a stereomicroscope and a of the twentieth century [1, 2]. Since 2004, however, the light microscope. Preparations were made in distilled water, investigations in the present Khorasan provinces have much 10% KOH and KI. The usual color tests were done by applying increased due to the development of local expertise. The total the reagents on the thallus or on exposed medulla [14]. The number of the species reported from the region represents the areoles of the thallus were separated under stereomicroscope crustose growth form as the dominant lichens [3–7]. Among and were extracted in acetone. Then the extractions were the genera is the well-known and conspicuous yellow- studied using two standard solvents, GAW and GE, on the green group of Rhizocarpon which is abundant in Arctic- basis of recrystallization of the soluble compounds [15]. Three Alpine environments worldwide. It grows very slowly (0.02– −1 specimens were subjected to thin-layer chromatography by 2mmyr ) and lives to a considerable age [8]. The present M.Kukwa(Gdansk,Poland),S.R.Clayden(NewBrunswick paper is part of a series of studies intended as contributions Museum, Canada), and the author by using solvent C. The towards a detailed treatment of Iran’s lichen biota. description below is based on these observations. Vouchers arestoredintheprivatecollectionoftheauthor. 2. Materials and Methods 3. Results Field investigations were made by a party of two people during May–November 2006 and July 2007 with some more 3.1. Rhizocarpon geographicum (L.) DC. collecting in 2011. A total of 15 sampling sites were visited, situated in Razavi Khorasan province (127432 sq.km), which 3.1.1. Description. The description: thallus spreading to 8 cm ∘ ∘ ∘ ∘ lies between 33 52 –38 17 N latitudes and 55 17 –61 15 E diameter, yellow-green to light yellow, composed of nearly longitudes in north-eastern Iran (Figure 1). The study area compacted areoles; black prothallus distinct at the thallus belongs to the Irano-Turanian phytogeographical region [9]. margin and more or less between the areoles; areoles 0.2– Calcareousbedrockispredominantinthestudyarea[10]and 1.4 mm in diameter, with less than one up to 4 areoles in 2 Journal of Mycology ∘ ∘ E56 0 00 E61 0 00 00 Turkmenistan Iran 0 ∘ 38 N Distribution map of Rhizocarpon geographicum (L.) DC. Scale 1 : 2800000 50050100 (km) N 00 Afghanistan 0 ∘ 33 N Collection area Province boundary International boundary Figure 1: Distribution of Rhizocarpon geographicum in Razavi Khorasan province, based on collected materials. (a) (b) Figure 2: (a) The position of the apothecium. (b) General habitat and margin of Rhizocarpon geographicum. 2 one mm , plane to strongly convex, surface not pruinose, green; hamathecial filaments anastomosing, hyaline, apically shiny, with incomplete secondary fissuring of areoles (Figures swollen. Epihymenium 15–30 m thick, greenish brown or 2(a)-2(b)), section of thallus in optical view K−,C−,or reddish brown, usually K−, seldom K+ reddish; without black rarely C+ red; secondary areoles angular, 0.2–0.4 mm in granules (Figure 4). Spores: 8/ascus, submuriform to muri- diameter, cortex pellucid, ca. 12–25 mthick;necroticlayer form,ellipsoid,occasionallywithconstrictedends,greenish very thin; medulla white, 80–150 m thick, I + violet; algal brown, 20–36 × 10–20 m, with 15–27 locules (Figure 5). layer continuous, 25–50 mthick,photobiontcellsrounded, (3–)5–8(–12) m diameter; hypothallus distinct, brown, 20– 3.1.2. Lichen Chemistry. Rhizocarpic acid and psoromic acid 60 mthick(Figure 3); not sorediate; pycnidia not observed. wereidentifiedbyTLC.Calciumoxalatewasdetectedby Apothecia mostly single, rarely 2-3 grouped together, microcrystal test and identified by its needle-shaped crystals. (0.3–)0.5–1.0(–1.2) mm diam., black, angular to roundish, usually plane or slightly convex, more or less pruinose, with 3.1.3. Distribution and Ecology. Rhizocarpon geographicum raised margin when young, usually surrounded by are- was found to be widespread in Razavi Khorasan [5, 6], except oles (Figure 2(a)), with 30–80 mthickbrownishproper in the west, where it has only been found at one locality. It excipulum. Subhymenium usually 30–100 mthick,dark is mainly distributed at middle elevation (Figure 1)andits brown. Hymenium 100–180 m tall, colourless to light altitude ranges from 1340 m to ca. 1870 m. Journal of Mycology 3 Figure 3: Transverse sections of secondary areoles with detailed views of layered structure; Co: cortex, Gl: gonidial layer, Me: medulla. Figure 4: Apothecium section; Ep: epithecium, Hy: hymenium, Ex: exipulum, Sh: subhymenium, Ht: hamathecium. (a) (b) Figure 5: (a) Asci with ascospores in K. (b) Mature ascospores. 4. Discussion faces. In its habitats R. geographicum is often the dominant species and often accompanied by thalli of the macrolichen In the R. geographicum-group the species R. geographicum Rhizoplaca melanophthalma and the crustose lichens A. isthemostwidespreadandknowntobeacommonspecies impressula, Aspicilia calcarea, R. geminatum, A. bullata, Calo- in all high mountains of the temperate regions [16]. This placa variabilis, Candelariella vitellina,andDimelanea oreina is in accordance with the observations in Iran, where it appeared to be common in most investigated areas of the andtwofolioselichens,Xanthoria elegans and Lecanoramu- province, while in the same area two further species of the ralis, while bryophytes are typically absent. This community geographicum-group, R. macrosporum and R. geographicum is very common and widespread in upland Razavi Khorasan, subsp. tinei, are represented by only three thalli [5, 6, 11, 13]. above1600m.TheassociatedspeciesofR. geographicum are R. geographicum is found on exposed siliceous rock faces, graphically presented in Figure 6. Where cyanolichens are closely associated with Acarospora impressula (Figure 6). dominant, R. geographicum is usually absent or of very low Rarely,ithasalsobeenfoundonverticalandshadedrock cover [6, 7]. 4 Journal of Mycology 60.00 48.39 50.00 % 40.00 38.07% 34.13% 33.45% 29.18% 30.00 (%) 20.00 18.86% 14.90 14.90 14.19 %14.23% %13.16 % % 9.96% 10.00 7.11% 7.82% 4.27% 4.22% 0.00 Other species ∗ Aspicilia calcarea Lecanora muralis Dimelanea oreina Dimelanea Xanthoria elegans Glypholecia scabra Glypholecia Acarospora bullata Acarospora Lecanora garovaglii Lecanora Caloplaca variabilis Caloplaca Candelariella aurella Acarospora anatolica Candelariella vitellina Acarospora impressula Acarospora Rhizocarpon disporum Rhizocarpon geminatum Rhizocarpon Rhizoplaca melanophthalma Figure 6: Graphic summary of redundancy analyses of adjacent species to R. geographicum (∗: observed species less than 10 times). Our observations on morphology agree with those of As R. geographicum is the dominant species among the other investigators. R. geographicum comprises discrete areo- knowntaxaofthegenusinNEIran[6, 11], it may be lae on a black hypothallus that extends beyond the areolae to recommended for lichenometric investigations in the region. form a marginal ring 2-3 mm in width [17]. It is representative of the geographicum-group, which is separated from other Conflict of Interests yellow-green taxa of Rhizocarpon by an indistinct epihymenium, a positive reaction of the medulla to iodine, and by The author declares that there is no conflict of interests pluriseptate ascospores. Within this group it is distinct by regarding the publication of this paper. the combination of epruinose apothecia, esorediate and not parasitic thallus, and ascospore size. The septation allows an Acknowledgments arrangement in four groups ranging from a few transverse septa to numerous septa in muriform ascospores [16]. The author would like to acknowledge S. Kamyabi for making The geographicum-group can be divided by three charac- his Rhizocarpon collection available to her. Special thanks are ter complexes: colour and shape of the areoles, the develop- due to Dr. Harrie Sipman for reviewing the paper. This work ment of the

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