G- J. Environ. Sci. Technol. 7(5): 54-59 (2020) ISSN (Online): 2322-0228 (Print): 2322-021X G- Journal of Environmental Science and Technology www.gjestenv.com RESEARCH ARTICLE Distribution, biomonitoring and conservation studies of pyrenocarpous lichens in India Gaurav K. Mishra, Sanjeeva Nayaka* and Dalip K. Upreti CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow-226001 Uttar Pradesh, INDIA Received: 15 Jan 2020; Revised: 18 Feb 2020; Accepted: 30 Mar 2020 ABSTRACT India is represented by the occurrence of the 382 species of pyrenocarpous lichens belonging to 49 genera and 12 families. Pyrenulaceae with six genera and 102 species is dominant family followed by Porinaceae with six genera and 88 species. Pyrenocarpous lichen genus Pyrenula with 82 species exhibits its dominance over Porina with 72 species. A total 25 pyrenocarpous genera are represented by a one or two species. The Western Ghats region exhibit rich diversity of pyrenocarpous lichens in India. The pyrenocarpous lichens commonly grows on smooth bark of trees or sometimes on rock, soil or leaves in tropical and temperate region of the country. Key words: Biodiversity; ecology; foliicolous; pyrenocarpous lichens; India 1) INTRODUCTION Pyrenocarpous or pyrenolichens are the group of lichens having flask shaped ascocarps (fruiting bodies) called perithecia. The lichens are externally discernible as patches of mostly dull shades of white, grey, straw, ochre, yellowbrown to brown with black dots of single or stramatoid, naked or covered perithecia. They are commonly growing on the bark of a number of trees or sometimes on rocks, soil or leaves in moist tropical and temperate regions of the world. Lichenological investigations in India have accumulated considerable information on Indian pyrenocarpous lichens. The revisionary studies on Indian pyrenocarpous lichens initiated simultaneously in the eighties of the last century carried out by various lichenologist [1,2,3,4]. Singh [5] reported the occurrence of 16 foliicolous species of genus Porina from Andaman Island, of which 15 were new records for India. Similarly, Singh [6] reported the occurrence of a single species Raciborskiella janeirensis (Müll. Arg.) R. Sant (=Strigula janeirensis (Müll. Arg.) Lücking) and listed four species of Strigula from Andamans. Singh [8] added Trichothelium epiphyllum Müll. Arg., from Nilgiri and Palni Hills. Awasthi and Singh [9,10] reported 14 foliicolous species of Porina from Nilgiri and Palni Hills, Porina nilgiriensis D.D. Awasthi & Kr. P. Singh and Porina palniensis D.D. Awasthi & Kr. P. Singh were new species and Porina chrysophora (Stirton) R. Sant., a new record for India. Patwardhan & Badhe [11] described Endocarpon pusillum Hedw. from Western India. Singh [12] reported Trichothelium abloratrum Vainio from Nilgiri and Palni Hills. Awasthi & Upreti [13] described three species of Dermatocarpon from India. Singh & Upreti [4] described two new species of Pleurotheliopsis andamanensis Ajay Singh & Upreti and Pleurotheliopsis ceylonensis Ajay Singh & Upreti (=Pyrenula astroidea (Fée) R.C. Harris and Pyrenula ceylonensis (Ajay Singh & Upreti) Aptroot) from India. Upreti & Singh [14] described a new species of Porina andamanensis Upreti & Ajay Singh from Andman Island. Upreti & Singh [15] provided the taxonomic account of ten species of Laurera (=Astrothelium) from India. Upreti [16] described ten species of Pyrenula, exhibiting Pyrenula subducta (Nyl.) Müll. Arg. spore type, of which seven species were new records to the Indian lichen biota. Awasthi [17] consolidated the information of different lichen genera in key of microlichens genera from India, Nepal & Sri Lanka and enumerated 229 species of pyrenocarpous lichens. Upreti [18,19,20,21,22] studied Pyrenula genus of pyrenocarpous lichens from India and reported several new records for Indian lichen biota. Upreti & Pant [23] reported nine species of Arthopyrenia from India, of which Arthopyrenia keralensis Upreti & G. Pant, was a new species. Upreti & Nayaka [24] reported Anisomeridium calcicolum Upreti & Nayaka, as new species and Lithothelium hyalosporum (Nyl.) Aptroot and Polymeridium albocinereum (Krempelh) R.C. Harries as new records for Indian lichen biota. Jagadeesh Ram et al. [25] revised the genus Pyrenula and reported Pyrenula subcylindrica Jagadeesh & Upreti new to science species from India. * Corresponding Author: Dr. Sanjeeva Nayaka Email address: nayaka.sanjeeva@gmail.com 54 The pyrenocarpous lichens communities are good indicator of young and regenerated forest type. The rich diversity of lichens clearly indicates that most of the forest within the eastern Himalayan region has good health of forest [26,27,28]. Among the different communities, foliicolous communities are more prone to microclimatic changes based on their substrate specificity and sensitivity. Sipman [29] observed that clearing of forest caused foliicolous lichen species to become discoloured and moribund. Some foliicolous lichens reappear in secondary/ regenerated forest but its frequency is lower as compared to primary forests [30]. A large number of pyrenocarpous lichens from different regions are collected in past and mentioned in a number of revisionary and monographic studies. However, biomonitoring and conservation related studies not done till date. Thus, the present study is based on the biomonitoring and conservation studies of pyrenocarpous lichens are provided. 2) 25 pyrenocarpous genera represent a single or two species each. Among the different growth forms of pyrenocarpous lichens corticolous dominant with 282 species followed by foliicolous with 56 species, whereas saxicolous and terricolous with 41 and 5 species respectively. Pyrenula immissa (Stirt.) Zahlbr., P. pinguis Fée, Porina internigrans (Nyl.) Müll. Arg., P. subcutanea Ach., P. subhibernica Upreti and P. tetracerae (Afz.) Müll. Arg., are the most common taxa in the country. Out of 384 species of pyrenocarpous lichens the country showed occurrence of 84 endemic species of which 23 species are known from Andaman & Nicobar Islands followed by 12 species from Karnataka (Fig.3). MATERIALS AND METHODS The present study is based on published literatures; herbarium specimens deposited in the CSIR-National Botanical Research Institute, Lucknow (LWG) and freshly collected specimens from different part of the country. Morphological and anatomical characters were examined using stereo zoom Leica S8APO and light DM2500 microscopes attached with camera. Thin sections of perithecia were cut using razor blade under stereoscope zoom microscope. All anatomical measurements were recorded in plain water, while 10% KOH was used for detailed study of asci and ascospores. For spot tests the usual reagents of K, C and P were used and for identification of lichens substance by thin layer chromatography (TLC) was performed in solvent system C following Orange et al. [31]. The specimens were identified up to species level with the help of keys of Awasthi [17], Aptroot [32], Aptroot et al. [33,34] and Aptroot [35]. The identified specimens deposited in CSIR-National Botanical Research Institute, Lucknow (LWG). Figure 1: Pyrenocarpous lichens family and their diversity in India. 100 80 60 40 20 0 72 82 38 25 12 19 10 3) RESULTS AND DISCUSSION India is represented by the occurrence of the 382 species of pyrenocarpous lichens belonging to 49 genera and 12 families. Pyrenulaceae family with six genera and 102 species showed its dominance followed by Porinaceae with six genera and 88 species (Fig. 1). Mycosphaerellaceae, Naetrocymbaceae, Stictidaceae, Strigulaceae and Tephromelataceae families in the country showed poor representation as represented by a single species of each family. The Western Ghats region exhibit 210 species of pyrenocarpous lichens in India. The Western Himalayan region has luxuriance of pyrenocarpous lichens due to its unique topography and climate condition represented 105 pyrenocarpous taxa. However, the Eastern Himalayan region has rich diversity with 295 species of pyrenocarpous lichens due to its warmer and moist climate condition. The rich moist and warmer climate in Eastern Himalayan region supports forest with dominance of evergreen tree vegetation. Lichen genus Pyrenula with 82 species exhibits its dominance over Porina with 72 species (Fig. 2). A total Figure 2: Pyrenocarpous lichens dominant genera in India Fig. 3: Pyrenocarpous holotype dominant states in India. Distribution of corticolous pyrenocarpous lichens: The pyrenocarpous lichens usually prefer a uniform, smooth substance to grow. It may be a rock, bark, or perennial leaf. 55 The most tropical areas are much preferred by the members of this group. As mentioned earlier in India the Western Ghats, coastal region including of Andaman Island and Eastern Himalayan forest exhibit a luxuriant growth of pyrenocarpous lichens. Both the Western and Eastern Himalayas bear good growth of a variety of smooth barked trees suitable for colonization of pyrenocarpous lichens. The submontane or lower regions (tropical and subtropical) of Siwalik and adjacent area in Western Himalaya have dominance of Shorea robusta trees with Dalbergia sesso, Cedrela toona, Syzygium cumini and Eugenia jaqmbolana. The young Shorea robusta trees in moist places bear Pyrenula immissa (Stirt.) Zahlbr. P. oculata A. Singh & Upreti, P. aspistea (Ach.) Ach. and few other pyrenocarpous species. The temperate or montane area in Western Himalaya is generally dominated by coniferous trees of Pinus, Cedrus deodara, Abies pindrow, Picea and Cuperssus. These threes have mostly thick and rough bark, which do not support colonization of many pyrenolichens. At higher altitudes the Alnus nepalensis, Aesculus indica, Quercus semecarpifolia, Q. dilatata are most common phorophytes of vegetation and bear good growth of Anthracothecium macrosporum (Hepp.) Müll. Arg., Lithothelium himalayense Upreti & Aptroot, Pyrenula platystoma (Müll. Arg.) Aptr, Pyrenula papillifera (Nyl.) Aptroot and other pyrenocarpous lichens. In Eastern Himalaya, the warm and humid weather is dominated with typical dense forests and the smooth bark trees that of Artocarpus type bear luxuriant growth of pyrenolichens. The temperate zone in Eastern Himalaya has luxuriant growth of Alnus and Michelia trees, most suitable for luxuriant growth of pyrenocarpous lichens. In the central Indian region mostly the species of Ficus, Syzygium, Artocarpous and Mangifera and Shorea robusta have smooth trunk bearing good growth of pyrenocarpous lichens. Andaman Island and costal vegetation like mangroves, beech forest and coconut and Arecha trees also bear excellent growth of pyrenocarpous lichens. The evergreen forest of Western Ghats and Eastern Himalayan region exhibit maximum diversity of pyrenocarpous lichens in India. The smooth bark trees along with streams in moist habitat bear diverse pyrenocarpous species mostly Porina and Pyrenula species on bark, leaves and rocks. Among the tropical forest of India, the tropical wet evergreen forest in west coast, Assam, West Bengal, and Andaman Islands have the richest diversity of pyrenocarpous lichens. The forests in the area are multistoreyed, made up of small trees, shrubs, lianas and dense ground vegetation. The dominant trees such as Dipterocarpous, Artocarpous, Mangifera, Michelia and some thick trunked climber’s bear diverse pyrenolichens. The tropical moist deciduous forests of Kerala, Karnataka, South Madhya Pradesh, Bihar, Bengal and Orissa are dominated by species of Terminalia, Grewia, Tectona, Melia, Delbergia and Shorea trees having mostly the dry and rough bark, supports poor growth of pyrenocarpous lichens. The montane subtropical forest found in hills of South India (Nilgiri Hills, Mahabaleshwar and Panchmarhi) between altitudes of (1000-2000 m) is cooler that the tropical and warmer than the temperate forest. The area also experience westerly wind, thus bear mostly the lichen elements cosmopolitan in distribution. This region exhibits the maximum diversity of almost all lichen taxa including the pyrenocarpous lichens. The ‘Sholas’ forests of this area are the excellent abode for a member of pyrenocarpous species. Among the different substrate, the pyrenolichens exhibit a special affinity for bark as compared to the rocks and leaves. The different phorophytes with smooth trunks, such as species of Alnus, Quercus, Ficus, Artocarpous, Shorea, Mangifera, Michelia and Celtis are preferred by the pyrenocarpous to colonize. Sometimes in Himalayas all the Quercus species is moist areas are preferred by pyrenolichens (particularly Anthracothecium and Pyrenula) that may be smooth, rough or undulating. Lithothelium himalayense Upreti & Aptroot requires an especial habitat to grow, usually this species grows on Quercus semecarpifolia trees near stream, which are frequently pruned for their leaves as fodder and exhibit stunted growth. The forest area is mostly thinned out, receive more light and wind. Alnus nepalensis a dominant phorophyte of both north and east Himalayan region exhibits luxuriant growth of pyrenocarpous lichens. The smooth bark with plenty of moisture allows a number of pyrenolichen taxa to colonize. Almost whole tree trunk together with thick branches bear continuous growth of pyrenocarpous taxa. Among the different species of Quercus; Q. semecarpifolia is temperate Himalaya bear good growth of pyrenolichens. The young trees and branches are preferred by the pyrenocarpous taxa while the old bark in mature trees is mostly devoid of this group. Some pyrenocarpous exhibit substrate specificity as they show restricted occurrence on single photophytes. The species of Astrothelium mostly grow on cashew nut trees in South India and Goa. Certain species of Pyrenula only grow on Alnus nepalensis, while Lithothelium species prefers hardwood trees with smooth bark. The species of Porina exhibit maximum substrate diversity as they grow on diverse trees, leaves and also on rocks. Anisomeridium species also grow on leaves, rocks and barks. Certain cultivated trees species like Mangifera indica, Artocarpous integra, Cocos nucifera, Citrus sp., Areca catehu, Anacardium orientalis, Hevea brasiliensis, Anacardium occidentale and Albizzia sp. seem to attract more pyrenocarpous lichens on their bark in the non-forested areas, than other naturally growing trees. Distribution and ecology of foliicolous pyrenolichens The foliicolous lichens found on certain leaves of very long durability. The fern fronds, phylloidia, perennial leaves of many shrubs and trees in moist shady places are the excellent habitat for foliicolous lichens. Among the different foliicolous lichens the species of Strigula elegans exhibit the maximum host diversity. It grows on Mangifera, Citrus and many more evergreen perennial leaves. The Porina species also exhibit wide host diversity, found growing on leaves of Palmae, Araceae, Liliaceae, Cycadaceae and more than 30 families of Angiosperms, Gymnosperms and Pteridophytes. The Strigula species mostly prefer the monocotyledonous genera, while Porina species mostly grow on fern genera and few monocotyledonous genera. The perennial shrubs 56 also bear luxuriant growth of foliicolous lichens such as Strigula antillarum (Fée) Müll. Arg., S. janeirensis (Müll. Arg.) Lücking, S. phyllogena (Müll. Arg.) R.C. Harris, Porina karnatakensis Makhija, Adaw. & Patw., P. nitidula Müll. Arg. and P. pallescens R. Sant. Exclusive topography and humid climate condition of Eastern Himalayan exhibit luxuriance of foliicolous lichens. Foliicolous lichen Porina genera dominance with 35 species followed by Strigula with 21 species in India. Eastern Himalayan region shows maximum diversity with 37 species, while Western Ghats exhibit 19 species of foliicolous taxa. Andaman and Nicobar Island has rich diversity of foliicolous lichens with 30 species [36, 37]. The humidity, light and other microclimatic condition play a much more important role for the occurrence of the foliicolous lichens. The anatomy and physiology condition of leaves also influence the growth of foliicolous lichens. The hairy as well as glossy leaves are not infrequency overgrown by lichens. The majority of foiliicolous lichens grow on the upwardly exposed leaf surface, while Strigula janeirensis (Müll. Arg.) Lücking grows regularly on lower surface of leaves [38]. Numerous species 15-25 of lichens usually grow together on the leaf surface and are considered very fast growing. In contrast to many other lichens they become fertile very quickly and so their generation may be very short. The foliicolous lichens occurs mainly in tropical rain forests, but also in other forests in more or less humid areas in tropical, subtropical and even in temperate zones and becoming gradually rare towards the alpine zone. The number of species in the temperate zones is low. Distribution of saxicolous pyrenocarpous lichens In India saxicolous species found growing on rock, monuments and old buildings in tropical, temperate and alpine region. Tropical regions of Kerala, Karnataka, Madhya Pradesh, Bihar, Bengal, Orissa, Uttar Pradesh and foot hills of Himalayas has luxuriant growth of Endocarpon nanum Ajay Singh & Upreti, E. pusillum Hedw., E. rosettum Ajay Singh & Upreti, Verrucaria elaeomelaena (A. Massal.) Arnold, and V. muralis Ach., while Endocarpon species mostly grow on monuments and old buildings. In temperate regions of Eastern and Western Himalaya most of saxicolous species Catapyrenium cinereum (Pers.) Körb., Dermatocarpon miniatum (L.) W. Mann., D. vellereum Zschacke, Endocarpon pallidulum (Nyl.) Nyl., Staurothele clopima (Wahlenb.) Th. Fr., S. fissa (Taylor) Zwackh, Thelenella brasiliensis (Müll. Arg.) Vain. and Verrucaria acrotella Ach. exhibit dominantly grows on calcicolous and another rock of the region. Dermatocarpon species luxuriantly grows in Western Himalayan region due to open thinned out area. Awasthiella indica Kr.P. Singh, monotypic genus reported from tropical region Manipur. Among the saxicolous pyrenocarpous lichens Catapyrenium and Dermatocarpon grows on soil over rocks in temperate and alpine areas, while Endocarpon, Staurothele and Verrucaria grows mostly on rocks from tropical to alpine areas. In alpine region the tree growth is almost absent and thus allows few pyrenocarpous to colonize on soil and rocks, such as species of Catapyrenium, Placidium, Endocarpon, Staurothele and Verrucaria. Distribution of terricolous pyrenocarpous lichens Eastern Himalaya has evergreen typical dense and moist forests exhibit dominance of Agonimia allobata (Stizenb.) P. James, A. opuntiella (Buschardt & Poelt) Vězda and A. tristicula (Nyl.) Zahlbr. species in Arunachal Pradesh, Assam and Sikkim, while Catapyrenium cinereum (Pers.) Körb., found in Maharashtra state. Due to warmer and open thin out forests in Western Himalaya lacking of terricolous pyrenolichen taxa. Biomonitoring of pyrenolichens The characteristic of lichens to accumulate substances is in more in use to monitor the air-transported pollution. The use of the lichen vegetation is a cheap means to map air contamination in an area. The foliicolous lichens are promising bioindicatiors in the tropics. Their dependency on the leaf on which they grow is limited, hence foliicolous lichens are mainly dependent on atmospheric factors for the survival. Foliicolous lichens exhibit an accelerated life cycle and immediately react upon environmental changes [39]. They are suitable for indication of the environmental parameters, as altitudinal zonation, reasonability, i.e. the amount of precipitation and their annual distribution and anthropogenic disturbance, together with micro-site, differentiating between light intensities in the shady understory, natural light gaps and the outer canopy. Good growth of the foliicolous lichens clearly indicates the shady and moist condition of the forest. All over the world the lichens growth of the lichens has been greatly influenced by the human activity. Mostly the pyrenolichens are corticolous in nature, their existence and growth is subjected to condition imposed on the tree species by human beings, sometimes promoting, sometimes hampering the growth of different taxa. In Andaman Islands and parts of Eastern Himalaya where many moist evergreen forests have undergone deforestation for a long time, the lichen growth occupied the deeper parts of such forests Sethy & Patwardhan [40] and Singh [8, 41]. Dense virgin forests that cover tracts of land in moist regions of the India subcontinent are suitable for growth of pyrenocarpous lichens. In very dense forests where light does not sufficiently penetrate to the ground level or the lower part of the tree, there is poor or no lichen growth on trees. The trees at fringes of such forests where they are thin, good lichen growth were observed. Thinning out of forests by human agency has extended the zone of lichen growth to deeper parts of such forests. Thinning out also promotes under growth that support rich growth of understory shrubs with foliicolous lichens. Road construction through dense forests, produce similar conditions, promoting lichen growth on the roadside trees. But in other part of the county like Indo-gangetic plain, major parts of Deccan plateau, the deforestation has been more or less complete, denying the lichens their substratum and creating dry conditions unsuitable for their existence. Conservation of pyrenolichens Upreti [42] mentioned the ethnobotanical commercial utilization of lichens and the decline of forests cover are the leading factors to loss of lichen diversity in India. Singh and Sinha [43] mentioned agricultural, urbanization, construction of road, buildings on hills, mineral extraction, hydroelectric projects, shifting cultivation, common 57 practice adopted by tribal societies in the entire northeastern states and excessive use of fire wood in hilly regions and preparation of charcoal by burring the trees (a common in hills of Meghalaya and north-west Himalayas) are another factor responsible for depletion of many lichen rich habitats. For conservation of the lichens in India, it is a need of the time that the areas having rich lichen biodiversity should be protected and declared as lichen sanctuaries In India, the tropical regions in Western Ghats, forest area along the coast, eastern Himalaya and Andaman Island harbor the rich pyrenocarpous lichen biota. Within these tropical zones some localities having rich diversity of pyrenocarpous lichen are in need of protection in the form of declaring the habitat as ‘Pyrenocarpous lichens Sanctuaries’. The areas having rich pyrenocarpous lichen diversity in India also need protection in the form of ‘Lichens Sanctuaries’. Upreti & Nayaka [44] already suggested few localities as ‘Lichen Sanctuaries’ in India. The Nilgiri and Palni Hills, Saryu river valley, Nain Singh top area in route to Milam glacier, Chopta Tungnath peak and Great Himalayan National Park (GHNP), are already protected areas under the boundaries of Nilgiri Biosphere Reserve, Nanda Devi Biosphere Reserve and Great Himalayan National Park, respectively. The Tiger Hill in West Bengal (Darjeeling), Phek district in Nagaland, Ranikhet in Uttarakhand, Amarkantak in Madhya Pradesh, Achanakamar in Chhattisgarh are also in need of protection in the form of describing the habitats as ‘Lichen Sanctuaries’. Only the declaration of ‘Lichen Sanctuaries’ is not sufficient for conservation of lichen in general and pyrenocarpous in particular. 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