Earthworm diversity at Nilgiri biosphere reserve, Western Ghats, India

Species diversity of earthworms in tropics is less studied compared to those of the temperate regions. Despite the fact that there have been numerous studies on earthworm diversity in the Western Ghats of India, there still exists scope for more earthworm species which are yet to be described. The present work involves a survey of earthworms in the Nilgiri biosphere reserve (NBR)—a part of a biodiversity hot spot of Western Ghats. Despite being a part of the biodiversity hot spot, studies on earthworm diversity at NBR are very limited. Unless an authentic record of earthworm species is made available, the consequence of human interference, habitat alteration or climate change on the species diversity cannot be assessed. An attempt has been made in this study to conduct a survey of earthworm species available in the selected forest ecosystems of the NBR. The findings of this study have shown that 84.67?% of the earthworm species identified is native, while the rest are exotic. On the basis of total number of earthworms collected, exotics accounted for 1.55?%, indicating the predominance of native species in the study area and indicating that this habitat is less disturbed. Among the species identified from Mukurthi, Priodochaeta pellucida is listed as vulnerable and has never been encountered since its discovery about 100?years ago. Shannon–Weiner indices showed that evergreen forests of Silent Valley have a high species diversity as do shola/grasslands of Mukurthi and moist deciduous forests of Muthanga.     

DNA barcoding of nymphalid butterflies (Nymphalidae: Lepidoptera) from Western Ghats of India

We have checked the utility of DNA barcoding for species identification of nymphalid butterflies from Western Ghats of India by using 650 bp sequence of mitochondrial gene cytochrome c oxidase subunit I. Distinct DNA barcoding gap (i.e. difference between intraspecies and interspecies nucleotide divergence), exists between species studied here. When our sequences were compared with the sequences of the conspecifics submitted from different geographic regions, nine cases of deep intraspecies nucleotide divergences were observed. In spite of this, NJ (Neighbour Joining) clustering analysis successfully discriminated all species. Observed cases of deep intraspecies nucleotide divergences certainly warrant further study.     

Exploring microbial bioactive molecules from Western Ghats,India

Western Ghats are designated as world heritage sites and global biodiversity hotspots. Microbial diversity in this forest area has been largely neglected and is getting attention since the end of the last millennium. In this review, we have studied and organized various microorganisms from Western Ghats and their diversity, important characteristics and potential biotechnological applications. Microorganisms from Western Ghats have been explored individually for potential bioactive molecules. While most of the microorganisms were analyzed for antimicrobial activities, there have been studies on microbial promotion of plant growth. The microbes analyzed included from aquatics, soil, rhizosphere, phyllosphere and even as endophytes. There have been microorganisms which have shown antioxidant and anti-cancerous activities. There are microorganisms capable of degrading plant wastes and also xenobiotics. Microorganisms capable of producing industrially important enzymes have also been reported. The present review explores largely neglected microbial diversity with respect to their ability to produce potential bioactive biomolecules.     

Alpha diversity of lianas in a tropical evergreen forest in the Anamalais, Western Ghats, India

Abstract. Species richness, abundance, size-class distribution, climbing mode and spatial patterns of lianas were investigated in a 30-ha permanent plot of tropical evergreen forest at Varagalaiar in the Anamalais, Western Ghats, India. Each hectare was subdivided into 10 m × 10 m quadrats, in which all lianas ≥ 1 cm d.b.h. were measured, tagged and identified. The total liana density was 11, 200 individuals (373 ha–1) and species richness was 75 species, representing 66 genera and 37 families. The richness estimators employed for species and family accumulation curves after 100 times randomization of sample order, have stabilized the curves at 16th and 15th hectares, respectively. A greater proportion of lianas was twiners (55% of species and 44.4% of density) and root climbers (5% of species and 14% of density), and a few were tendril climbers, reflecting the late successional stage of the forest. In the size-class distribution, 82% of abundance and 97% of species richness fell within 1–3 cm diameter threshold. The dominance of succulent diaspore type signifies the faunal dependence of lianas on vertebrate frugivores for dispersal. The diversity, population density and family composition of lianas of our site is compared with those of other tropical forests. The need for biomonitoring of this synusia in the permanent plot for forest functioning is emphasized.     

Plant diversity,structure and regeneration potential in tropical forests of Western Ghats,India

Diversity, stand structure and regeneration potential are the key elements of any forest ecosystem. For the present study, seven sites were selected with the aims of assessing plant diversity, structure and regeneration potential in tropical forests across Kanyakumari Wildlife Sanctuary (KWLS), Western Ghats, India. The sites were classified based on the similarity: tropical dry deciduous sites (TDDs I and II), tropical semi-evergreen sites (TSEs I and II) and tropical evergreen sites (TEFs I-III). The phytosociological survey was done by laying a total of 70 plots (10 plots in each study site). Standard methods were followed for the assessment of diversity, structure and regeneration patterns. A total of 267 species (205 genera, 70 families) were recorded. The tree species richness ranged 24 (TDD II) – 76 (TEF III). Of the vegetation spectrum, trees, vines and understorey accounted 56.5, 15.3 and 28.2% respectively to the total flora documented. A total of 66 species were endemic. The total tree density and tree basal area (seedlings, saplings, juveniles and adults) were 18,790 individuals (mean 2684) and 137.6 m² (mean 19.7 m²) in 70 plots respectively. The mean tree adult density and basal area ranged 370 (TDD I) – 900 (TEF I) individuals/ha and 24.2 (TDD I) – 75.3 (TEF III) m²/ha respectively. The overall species richness was highest in TDD I, but TEF III had the highest tree species richness. The diameter class-wise distribution showed the characteristic ‘reverse J-shaped’ curve. Most tree species were ‘newly recruited’. The dominant species had ‘fair’ to ‘good’ regeneration potential. However, 12 tree species showed ‘no’ regeneration. The overall regeneration pattern of trees was ‘good’, but ‘no’ or ‘poor’ regeneration patterns in some tree species, especially endemics is a point of concern. Since a majority of tree species were ‘new recruits’, species composition may likely change in the future. The results obtained would help in understanding diversity patterns, structural attributes and regeneration potential in tropical forests of protected areas for better forest management and conservation.     

Patterns in diversity of anurans along an elevational gradient in the Western Ghats, South India

Aim To examine patterns in anuran species richness along an elevation gradient and identify factors that govern anuran species richness on a tropical elevational gradient. Location Sampling for anurans was carried out in Kalakad Mundanthurai Tiger Reserve (KMTR) in the southern Western Ghats, India. Methods Night‐time sampling for anuran species richness was carried out from 20 November 2004 to 20 April 2005, during the north‐east monsoon and dry seasons, using transects (50 × 2 m) and visual encounter surveys along the streams. The entire gradient was classified into thirteen 100‐m elevation zones. Sampling at the alpha (single drainage basin) level was carried out in the Chinnapul River drainage basin (40–1260 m a.s.l.) and at the gamma (landscape) level in four drainage basins. Additionally, published records were used to arrive at an empirical species richness (S) for the entire landscape. Mid‐Domain Null software was used to test for the possible influence of geometric constraints on anuran species at both the alpha and gamma levels. The influence of area under each elevation zone on empirical S was tested. The pattern in anuran species richness along the elevational gradient was investigated using: (1) species boundaries in each elevation zone and their habitat correlates, (2) abiotic factors as predictor variables, (3) mean snout vent lengths of anurans, and (4) correlation between the matrices of distance in the elevation zones based on microhabitat parameters and species composition. Cluster analysis on species presence–absence in the elevation zones was used to categorize the entire gradient into high, middle and low elevations. In these three elevation categories, pattern in composition of species was examined for endemism in Western Ghats–Sri Lanka biodiversity hotspot, uniqueness to an elevation zone, adaptations of adults and modes of breeding. Results Species richness at the alpha level increased linearly with elevation, while at the gamma level there were three peaks. Maximum species richness was observed at the highest elevation (1200 m) at both the alpha and the gamma levels. The observed patterns differed significantly from mid‐domain null predictions. The multi‐modal pattern in species richness was a consequence of overlapping species range boundaries. Soil temperature was the best single measure in explaining the majority of variation in species richness at the alpha level (r² = 0.846, P < 0.01). However, soil moisture was the best predictor when both the alpha and the gamma sites were pooled (r² = 0.774, P < 0.01). Anuran body size decreased with an increase in elevation. The highest proportions of endemic and unique species were found at high elevations (> 700 m). The proportion of arboreal anurans increased from low to high elevation. Anurans exhibiting direct development were predominantly found at high elevations. Main conclusions Geometric constraints did not influence anuran species richness along the elevational gradient. Overlapping range boundaries influenced species richness at the gamma level. Abiotic factors such as soil temperature and moisture influenced anuran species richness in the mountain range. The ‘Massenerhebung effect’ could be responsible for range restriction and endemism of anurans, differences in guilds and mode of reproduction. These findings highlight the importance of cloud forests for endemic anurans.     

Genetic structure and diversity of Coscinium fenestratum: a critically endangered liana of Western Ghats,India

Coscinium fenestratum is a critically endangered medicinal plant, well-known for its bioactive isoquinoline alkaloid berberine. The species has been over harvested from its natural habitats to meet the huge requirement of raw drug market and industrial consumption. This has lead to a rapid decline in the population size and has also led to local population extinction at few locations in the Western Ghats, India. In this study, inter-simple sequence repeat markers were used to investigate the genetic variation and population structure of seven extant populations of C. fenestratum from the central Western Ghats, India. Eight primer combination produced a total of 57 unambiguous bands, of which (47.1 %) were polymorphic. The species exhibited a moderate to low level of intra population genetic diversity (H _s = 0.347 ± 0.008; H _t = 0.378 ± 0.006 (POPGENE) and H _s = 0.262 ± 0.0028; H _t = 0.204 ± 0.020 (HICKORY)). The populations were low to moderately differentiated from one another (G _ST = 0.221) and geographical distance was not significantly correlated with genetic distance, suggesting that these long-lived, geographically distant remnant populations were once connected through gene flow. There was a significant amount of genetic variation among populations (19.85 %). The Bayesian software STRUCTURE and HICKORY were used to further reveal the genetic structure of C. fenestratum. The results revealed weak population structure (K = 2) with one single widespread gene pool, and indicated that gene flow and inbreeding are likely to be the major driving force in shaping current population genetic structure of C. fenestratum. Thus, an understanding of the genetic diversity and population structure of C. fenestratum can provide insight into the conservation and management of this species.     

Tree species diversity and community composition in a human-dominated tropical forest of Western Ghats biodiversity hotspot,India

The structure, function, and ecosystem services of tropical forest depend on its species richness, diversity, dominance, and the patterns of changes in the assemblages of tree populations over time. Long-term data from permanent vegetation plots have yielded a wealth of data on the species diversity and dynamics of tree populations, but such studies have only rarely been undertaken in tropical forest landscapes that support large human populations. Thus, anthropogenic drivers and their impacts on species diversity and community structure of tropical forests are not well understood. Here we present data on species diversity, community composition, and regeneration status of tropical forests in a human-dominated landscape in the Western Ghats of southern India. Enumeration of 40 plots (50 m × 20 m) results a total of 106 species of trees, 76 species of saplings and 79 species of seedlings. Detrended Correspondence Analysis ordination of the tree populations yielded five dominant groups, along disturbance and altitudinal gradients on the first and second axes respectively. Abundant species of the area such as Albizia amara, Nothopegia racemosa and Pleiospermum alatum had relatively few individuals in recruiting size classes. Our data indicate probable replacement of rare, localized, and old-growth ‘specialists’ by disturbance-adapted generalists, if the degradation is continuing at the present scale.     

Genetic diversity across natural populations of three montane plant species from the Western Ghats, India revealed by intersimple sequence repeats

We analysed genetic diversity across the natural populations of three montane plant species in the Western Ghats, India; Symplocos laurina, Gaultheria fragrantissima and Eurya nitida using intersimple sequence repeat (ISSR) markers. These markers revealed genetic diversity within the populations of these plants from Nilgiri and also between two populations of S. laurina from Nilgiri and Amboli. Genetic variation within and between populations was analysed using various parameters such as total heterozygosity (HT), heterozygosity within population (HS), diversity between populations (DST), coefficient of population differentiation (GST), genetic distance (D) and gene flow (Nm). Total heterozygosity (HT) was higher for S. laurina (0.238) than for G. fragrantissima (0.172) and E. nitida (0.182). Two populations of S. laurina, separated by > 1000 km, showed a high within-population variation (53.7%) and a low gene flow (Nm = 0.447). upgma phenograms depicted a tendency of accessions to group according to their geographical locations in all the three plant species. The insight gained into the genetic structure of these plant populations might have implications in developing in situ and ex situ conservation strategies.     

Changes in rain forest tree diversity, dominance and rarity across a seasonality gradient in the Western Ghats, India

Aim We assessed the effects of latitude, altitude and climate on the alpha diversity of rain forest trees in the Western Ghats (WG) of India. We tested whether stem densities, dominance, the prevalence of rarity, and the proportion of understorey trees are significantly correlated with alpha diversity. Location The WG is a chain of mountains c. 1600 km in length, running parallel to the western coast of the Indian peninsula from above 8° N to almost 21° N latitude. Wet forests occur as a narrow strip in regions with heavy rainfall. Methods To assess tree diversity we used data from 40 small plots, < 1 ha in area, where all trees ≥ 3.18 cm d.b.h. had been inventoried. These plots were distributed across 7 latitudinal degrees and at elevations between 200 and 1550 m. Fisher's alpha was used as a measure of diversity. For each plot, the proportion of trees belonging to the understorey, the proportion of trees belonging to the most abundant species in the plot, as a measure of dominance, and the proportionate representation of singletons, as a measure of rarity, were estimated, and correlated with Fisher's alpha, elevation, rainfall and seasonality. Results Annual rainfall and seasonality increased towards the north, but were not significantly correlated. Tree diversity increased significantly with decreasing seasonality. Tree diversity was not significantly correlated with stem density or with the proportion of understorey tree species, but was significantly correlated with tree dominance and rarity. Dominance increased and rarity significantly decreased with increasing seasonality. Main conclusions This study demonstrates that seasonality influences rain forest tree diversity in the WG of India. The relationship between alpha diversity, dominance and rarity lends correlative support for the Janzen–Connell pest pressure hypothesis.     

Gomphia barberi,a new species of Ochnaceae from Tirunelveli Hills,Western Ghats of India

Gomphia barberi sp. nov. (Ochnaceae) is described with an illustration from the Tirunelveli Hills of southern Western Ghats of Tamil Nadu, India.     

Pinda shrirangii,a new elegant species of Apiaceae from the northern Western Ghats,India

A new species, Pinda shrirangii Gosavi & Chandore, is described and illustrated from a high-elevation region of northern Western Ghats, India. The new species is closely allied to the only other species in the genus, Pinda concanensis (Dalzell) P.K.Mukh. & Constance which was also described from the northern Western Ghats of Maharashtra state of India. Coloured photographs and illustrations are provided to facilitate the identification.     

Agni's fungi: heat-resistant spores from the Western Ghats, southern India

This study concerns the thermotolerance of spores of mesophilic fungi isolated from a tropical semi-arid habitat subject to dry season fire in the Western Ghats, southern India. Among 25 species of Ascomycota isolated from leaf litter, nine were able to grow after incubation in a drying oven for 2h at 100°C; the spores of two of these species survived 2h incubation at 110°C, and one survived exposure to 115°C for 2h. The range of thermotolerance among mesophilic fungi isolated from the leaf litter was surprising: filamentous fungi from other habitats, including species that colonize scorched vegetation after fires and thermophilic forms occurring in self-heating plant composts, cannot survive even brief exposure to such high temperatures. It is possible that the exceptional heat resistance of the Indian fungi is related to adaptations to surviving fires. Genetic analysis of the physiological mechanisms of heat resistance in these fungi offers prospects for future biotechnological innovations. The discovery of extreme thermotolerance among common saprotrophs shows that this physiological trait may be more widespread than recognized previously, adding to concern about the evolution of opportunistic pathogens on a warmer planet. The fungi in this study are among the most heat-resistant eukaryotes on record and are referred to here as 'Agni's Fungi', after the Hindu God of Fire.     

The sacred groves of Western Ghats in India

Then ignoring the pleadings of the king, she wandered into the sacred grove of Kumara. Her mind bewildered by the curse of her Guru, she failed to notice this transgression into an area forbidden to women. No sooner did she enter, than she was transformed into a vine clinging to a tree at the boundary of the grove. Kalidasa in Vikramorvasiyam (c. 300 A.D.)     

New species of Phaeoramularia, Pseudocercospora and Stenella from Western Ghats of India

Four new species of the hyphomycete genera Phaeoramularia viz. Ph. caesalpinae, Pseudocercospora viz., Ps. tiliacearum, Stenella, viz. S. argyreiae and S. grewiae occurring on Caesalpinia bonducella Fleming (Caesalpiniaceae), Grewia sp. (Tiliaceae), Argyrea sp. Lour (Convolvulaceae) and Grewia sp. L. (Tiliaceae), respectively are described and illustrated here. All these fungi were collected from Western Ghats of India.     

A new species of Cycas from the Malabar Coast, Western Ghats, India

A new cycad species,Cycas annaikalensis, has been discovered from the Malabar Coast of the southern Western Ghats of India. Although geographically distributed in a small population within the range ofC. circinalis, it can be distinguished from the other described IndianCycas species by its distinct habitat, habit, morphology of vegetative and reproductive parts, and anatomy of leaflets.     

Psychotria henryana (Rubiaceae), a new species from the southern Western Ghats,India

Psychotria henryana (Rubiaceae), a new species from the hills of Tirunelveli and Kanyakumari districts in Tamil Nadu at the core zone of Kalakad‐Mundanthurai Tiger Reserve and Agasthiyamalai Biosphere Reserve on the southern Western Ghats of India, is described and illustrated.