Bergmann’s rule predicts a larger body size for endothermic organisms in colder environments. The contrasting results from previous studies may be due to the differences in taxonomic (intraspecific, interspecific and community) and spatial (latitudinal vs elevational) scales. We compared Bergmann’s patterns for endotherms (Aves) and ectotherms (Lepidoptera: Sphingidae) along the same 2.6 km elevational transect in the eastern Himalayas. Using a large data spanning 3,302 hawkmoths (76 morpho-species) and 15,746 birds (245 species), we compared the patterns at the intraspecific (hawkmoths only), interspecific and community scales. Hawkmoths exhibited a positive Bergmann’s pattern at the intraspecific and abundance-weighted community scale. Contrary to this, birds exhibited a strong converse Bergmann’s pattern at interspecific and community scales, both with and without abundance. Overall, our results indicate that incorporation of information on intraspecific variation and/or species relative abundances influences the results to a large extent. The multiplicity of patterns at a single location provides the opportunity to disentangle the relative contribution of individual- and species-level processes by integrating data across multiple nested taxonomic scales for the same taxa. We suggest that future studies of Bergmann’s patterns should explicitly address taxonomic and spatial scale dependency, with species relative abundance and intraspecific trait variation as essential ingredients especially at short elevational scales.

The Tuting–Tidding Suture Zone (TTSZ), exposed along Dibang and Lohit river valleys in Arunachal Himalaya, NE India, is the easternmost continuation of the Indus–Tsangpo Suture Zone (ITSZ) and consists of ophiolites associated with metabasics and carbonates. Amphibolites, existing at the base of the ophiolite complex, were studied using whole-rock, mineral chemical analyses and pressure–temperature (P-T) pseudosection modelling to understand their metamorphic and petrogenetic history, and interpret the tectonic environment of their formation. They exhibit two-stage deformation, where D1 is depicted by polymineralic inclusion trails in former melt pools and the main foliation represents D2. Sub-alkaline tholeiitic character, high-field-strength element (HFSE) ratios and mid-oceanic ridge basalt (MORB) -like rare earth element (REE) patterns with negative Eu anomaly indicate that the protolith of these amphibolites originated in a spreading regime by extensive partial melting of a depleted mantle source at shallow depth. Petrography, mineral chemistry and P-T modelling indicate a three-stage metamorphic history for them. M1 is the prograde (c. 2.1 GPa, c. 450°C) defined by garnet centre compositions corresponding to the D1 event. The existence of former melts in the samples demarcates the M2 stage (1.4–1.8 GPa, c. 600°C). The rocks later underwent retrogression (M3: 0.8–1.0 GPa, 480–520°C), which corresponds to the D2 event. These observations suggest that the protolith of the TTSZ amphibolites originated in a mid-oceanic ridge setting, which accreted below a subduction zone where it underwent M1 metamorphism followed by M2 metamorphism, corresponding to partial melting of the rocks. Finally, the M3 event occurred during the obduction phase of the ophiolite complex, where the amphibolites were obducted as the metamorphic sole of the TTSZ ophiolites.

The White-bellied Heron Ardea insignis is currently known to be restricted to Bhutan, Myanmar, and north-east India. This ‘Critically Endangered’ species is under threat from the ever-changing river systems, primarily due to anthropogenic pressures including the large number of proposed hydropower projects. We report results of the first systematic, large-scale river survey for this species in the states of Arunachal Pradesh and Assam in north-east India with the aim of establishing its evidence-based distribution and assessing the severity of threats on the river systems in the region. We conducted river surveys along all seven major river basins in Arunachal Pradesh (October 2017–March 2018) and one in Assam (January 2019) along with 200 key informant surveys from 23 localities across the region. We encountered the White-bellied Heron six times in only three of 81 sites surveyed. Three interviewees reported observing the herons in three new localities, but we did not have a direct observation of the birds in any new sites. From field observations during the river surveys as well as the interview results, we found that certain fishing methods, garbage, and sand/gravel mining could be potential reasons for restricted occurrence of the White-bellied Heron in the region. Hunting is also a threat that prevails across the region. Our study calls for governmental commitment for the protection of the species and its vulnerable ecosystem and focussed research on understanding the anthropogenic impacts on the heron.

An account of thelotremoid species of Graphidaceae in India is provided, which includes 124 species in 24 genera. Ocellularia and Thelotrema are the most diverse genera represented by 34 and 18 species, respectively. Type specimens were re-examined and additional samples studied morphologically and chemically. One new species, Ocellularia upretii S. Joshi, Divakar, Lumbsch & Lücking, is described; it is characterized by a greyish green thallus, porinoid ascomata, brown proper exciple, simple, carbonized columella, clear hymenium, transversely septate, amyloid ascospores of 110–125×15–20 µm and an absence of secondary metabolites. Asteristion australianum, Astrochapsa mirabilis, Cruentotrema cruentatum, C. kurandense, Ocellularia violacea and Thelotrema adjectum are reported as new to the country, and Astrochapsa mirabilis, Melanotrema submicrosporoides, Ocellularia annuloelevata, O. subkeralensis and Rhabdodiscus verrucoisidiatus are proposed as new combinations. Diploschistes awasthii, Ocellularia gupeti, O. leucina, O. mahabalei, Thelotrema confertum and T. verrucorugosum are synonymized under D. scruposus, O. neomasonhalei, O. urceolaris, O. thelotremoides, Chapsa leprocarpoides and T. rugatulum, respectively, with Ocellularia canariana and O. verrucomarginata reduced to synonymy with O. allosporoides.

Outcrop-scale structures and magnetic fabric anisotropy of the Bomdila Gneiss (BG) that intruded the Lesser Himalayan Crystallines (LHC) of the Arunachal Lesser Himalaya are studied to understand the BG deformation history and tectonic evolution. Detailed analysis of structures reveals that the LHC have undergone three phases of deformation, D1, D2 and D3. The S2 foliation developed during the second phase of deformation (D2) is the most penetrative planar fabric in the studied rock, which shows a general ENE–WSW strike with moderate NW dip. Mesoscopic evidence of a later phase of deformation (D3) in the BG is lacking. Evidence of D3 deformation in the form of F3 folds is only observed in the adjacent metasedimentary rocks of the LHC. The magnetic foliations recorded from anisotropy of magnetic susceptibility (AMS) analysis of the BG are mostly striking NW–SE with a moderate dip towards the NE or SW, and magnetic lineation is mostly sub-horizontal and dominantly plunging towards the SE. Our study shows that the magnetic fabric of the BG does not correspond to any visible outcrop-scale mesoscale foliation. However, the magnetic foliation of the BG is parallel to the axial plane of the F3 folds of the adjacent metasedimentary rocks of the LHC. Integration of AMS and outcrop-scale structural analysis helps us envisage the superposed deformation history of the BG. Our study emphasizes the importance of AMS to detect late-stage or feeble deformation events that leave no visible outcrop-scale imprint and are difficult to discern through conventional geological means.

A new species of Kuepferia (Gentianaceae), K. pringlei D.Maity & Sentu K.Dey from north Sikkim, Eastern Himalaya, is described and illustrated. Details of habitat, phenology and conservation status are given, and it is compared to related species. This previously undescribed species is most similar to, but distinct from, Kuepferia leucantha (Harry Sm. ex T.N.Ho & S.W.Liu) Adr.Favre, known from Bhutan and China.

The fruit-tracking hypothesis predicts a positive association between frugivores and fruit abundance over space and time. We documented hornbill diets and examined the relationship between fruit abundance and abundance of three hornbill species (Buceros bicornis, Rhyticeros undulatus and Aceros nipalensis) in the Eastern Himalaya from 2009–2012. The study was carried out at three scales: at the largest scale of the study area (15 km2), at the intermediate scale – eight 3-ha patches within the study area and at the smallest scale of individual fruiting trees. Ninety-one per cent of the 64 foraging sightings of the great hornbill were on figs while more than 50% of the foraging sightings of the wreathed (83) and rufous-necked hornbills (87) were on non-fig fruits. At the largest scale, wreathed hornbill abundance and ripe fruit abundance peaked in the non-breeding season. At the intermediate scale, wreathed hornbill abundance was positively associated with non-fig fruit availability while rufous-necked hornbill abundance was negatively associated with non-fig fruit availability. At the smallest scale, great and rufous-necked hornbill abundances were correlated with fig and non-fig fruit crop sizes, respectively. The three hornbill species track fruit availability at different scales based on diet, which has implications for their role in seed dispersal.

A new species, Adinandra kamalae M.K.Pathak, Bhaumik & G.Krishna (Pentaphylacaceae), is described from Upper Siang District, Arunachal Pradesh, India.

During 2008–2010 we investigated the ecology of the Endangered dhole or wild dog Cuon alpinus in Khangchendzonga Biosphere Reserve in the Eastern Himalaya in Sikkim, India. We conducted camera trapping (n = 71 sites, 6,278 camera-days) and sign surveying along trails (n = 24; 629.43 km of effort) to assess the relative abundance, distribution and activity pattern of the dhole. Morphological characteristics evident in the 61 camera-trap photographs indicate that the dhole population in the Reserve may be the rare and genetically distinct subspecies C. alpinus primaevus. We detected dholes over a wide elevation range (2,501–4,100 m) that encompassed the upper temperate, subalpine, and alpine scrub zones. Dholes were diurnal, with peak activity at 08.00–10.00. Analysis of 41 scats indicated a diet comprising mainly mountain ungulates, rodents and pikas Ochotona sp. Although the frequency of occurrence of rodents was highest (32%) in the scats, 98.7% of the total biomass consumed was of mountain ungulates. Historical reports (1888–1894) indicated that the dhole was formerly abundant in Sikkim but was hunted to meet the high demand for its alleged medicinal properties. With no information on the status of the dhole in Sikkim for over a century, our study suggests that the species is now rare in the Reserve. To aid the conservation of the dhole and its main ungulate prey species extensive research and monitoring are required in the Reserve and elsewhere in the Eastern Himalaya.

A well-documented karyo-morphological analysis has been presented in one unexplored cultivar of Capsicum annuum L., collected from South Sikkim, India, to determine the chromosome number. This report confirms that the cultivar contains 2n = 48 chromosomes, which are not produced through self-duplication. More studies are required to determine its actual taxonomic position and genetic relationship with other cultivars and species. This cultivar of C. annuum provides a new, unexplored genetic resource with a high chromosome number.

The recently-described Arunachal macaque Macaca munzala is so far known only from western Arunachal Pradesh, north-east India. Here we present the first conservation status assessment for the species. Our surveys enumerated a total of 569 individuals in the Tawang and West Kameng districts of the State. The species seems to be tolerant of anthropogenic habitat change but is vulnerable to hunting. A low infant to adult female ratio suggests that not all adult females reproduce at any given time, and females do not give birth every year. The macaques are persecuted largely in response to crop damage, with the practice of keeping them as pets providing an added incentive to hunting. The species is, however, able to attain remarkably high densities in the absence of hunting. Crop damage by the macaque is widespread; patterns of crop damage are similar across altitudinal zones and do not seem to be correlated with macaque density. The species will need to be protected in human-modified landscapes, and the issues of crop damage and retaliatory persecution need to be addressed urgently.

The high altitudes of Arunachal Pradesh, India, located in the Eastern Himalaya biodiversity hotspot, remain zoologically unexplored and unprotected. We report results of recent mammal surveys in the high altitude habitats of western Arunachal Pradesh. A total of 35 mammal species (including 12 carnivores, 10 ungulates and 5 primates) were recorded, of which 13 are categorized as Endangered or Vulnerable on the IUCN Red List. One species of primate, the Arunachal macaque Macaca munzala, is new to science and the Chinese goral Nemorhaedus caudatus is a new addition to the ungulate fauna of the Indian subcontinent. We documented peoples' dependence on natural resources for grazing and extraction of timber and medicinal plants. The region's mammals are threatened by widespread hunting. The snow leopard Uncia uncia and dhole Cuon alpinus are also persecuted in retaliation for livestock depredation. The tiger Panthera tigris, earlier reported from the lower valleys, is now apparently extinct there, and range reductions over the last two decades are reported for bharal Pseudois nayaur and musk deer Moschus sp.. Based on mammal species richness, extent of high altitude habitat, and levels of anthropogenic disturbance, we identified a potential site for the creation of Arunachal's first high altitude wildlife reserve (815 km2). Community-based efforts that provide incentives for conservation-friendly practices could work in this area, and conservation awareness programmes are required, not just amongst the local communities and schools but for politicians, bureaucrats and the army.

Medicinal plants are a valuable resource for regional economic development in the tropics, and the Eastern Himalaya in particular harbours many such species. Extensive deforestation and over-exploitation in this region have brought several species to the brink of extinction, and Coptis teeta is such an endangered species; yet scientific information for its conservation is lacking. Investigations on the distribution range, demography, ecology, cytology, reproductive biology and population genetic structure of C. teeta were carried out; it was found to be endemic to a small area, to occupy a very narrow habitat and to be highly dispersed with very small population sizes. Edaphic factors were found to have played a vital role in ecological preference, natural distribution and evolutionary divergence of the species. The species exhibits a ‘K’ strategy, high male sterility, low reproductive success and efficiency, inadequate seed dispersal, and little genetic variability. A combination of these genetic hurdles and external threats in the form of habitat disturbance and over-exploitation for commercial purposes could result in its extinction. The species was found to have highly specific microsite requirements that cannot be met in other habitats. It is argued that in situ conservation measures would be the best strategy for the continued survival of this species. For effective management of the species it is recommended that its habitat be declared a protected area with the active cooperation of local inhabitants including the sharing of benefits of conservation.