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Habenaria diphylla (Nimmo) Dalzell, is a tuberous geophytic orchid that thrives in wet tropical biomes and grassy hill slopes. Presently, a Maximum Entropy (MaxEnt) Modelling approach was used to estimate the potential distribution of Habenaria diphylla in Kerala, India, considering both present and future climatic scenarios. The MaxEnt model predicted habitat suitability for H. diphylla with an area of approximately 1344 km², showing high probability zones concentrated in the Northern parts of Kerala and it was revealed that Bio17 (precipitation of driest quarter), Bio12 (annual precipitation), solar radiation (March), and Topographic Position Index (TPI) were the most significant predictor variables influencing distribution of H. diphylla. Habitat suitability for H. diphylla was projected under future climate scenarios (2020-2100) using Shared Socioeconomic Pathways (SSPs) 126, 245, 370, and 585. Under SSP370 and SSP585, highly suitable areas for H. diphylla decreased by 73.2% and 0.35% respectively by 2080-2100, due probably to an increase in temperature and declining rainfall.

Three orchid species namely, Bulbophyllum gibbosum (Blume) Lindl., B. odoratissimum (Sm.) Lindl. ex Wall., and Dendrobium albopurpureum (Seidenf.) Schuit. & Peter B.Adams, were collected from Rangamati Hill District and have been reported here as new angiospermic records for Bangladesh flora. The detailed critical examination of the specimens of these species has been made to confirm their taxonomic identification. The present communication reports their detailed taxonomic descriptions along with flowering time, ecology, geographical distribution, illustrations, and photographs.

Coelogyne flaccida Lindl. is a rare pseudobulbous epiphyte having considerable therapeutic as well as medicinal potential. The present investigation describes a protocol for mass propagation of this conservation reliant orchid. About 95% and 78% germination was recorded on half strength MS basal medium and Knudson C medium fortified with 3% sucrose, 0.8% agar, 10% coconut water, and 0.3% activated charcoal within 4 and 8 wks of culture respectively. Protocorm multiplication was induced on half strength MS basal medium fortified with varying concentrations (0.5-2.0 mgL-1) of TDZ, BAP, and KN along with 0.5 mgL-1 NAA and 0.5 mgL-1 IBA. A notable increment in shoot number was noticed when protocorm derived explants were exposed to varying levels of additives like adenine sulphate and banana homogenate. Rooting (100%) was obtained on half strength MS basal medium fortified with varying concentrations of IBA (0.5-2.0 mgL-1). After 3 months of initial acclimatization, the seedlings/plantlets exhibited appreciable growth and a healthy survival rate (85%).

Orchid Herbarium Tippi (OHT) at West Kameng district, Arunachal Pradesh, India has the collection of orchid species from different parts of the state, having a total deposition of about 2700 herbarium sheets representing 142 orchid genera. The present communication deals with 25 holotype specimens, some of which have also been deposited in ARUN, APFH, ASSAM, and CNH (CAL) herbarium as a Paratype sheets. The present study provides the brief notes including locality, habitat, distribution, description, and collection numbers of these 25 species from 16 genera.

Vanda tessellata (Roxb.) Hook. ex G.Don (Orchidaceae) is an epiphytic plant mostly found in moist to dry deciduous forests and is distributed in different parts of India, Sri Lanka, Nepal, Bangladesh, Myanmar, Vietnam, and China. It possesses antioxidant, cytotoxicity, and anti-microbial activities. Due to its medicinal properties, it is used by traditional healers to treat many ailments. Apart from medicinal uses, it also has a vital role in ecological aspects. Its populations are declining due to over-exploitation for its traditional medicinal uses which has caused pressure on its populations. There have been very limited efforts to address conservation concerns, such as mapping of the distribution pattern. Therefore, the present study was carried out to predict the current and future suitable distribution of V. tessellata in India using MaxEnt species distribution model. Output of MaxEnt model revealed that the suitable habitat for distribution is Central and Southern part of India, with a significant area of 1,57,285 km2. When compared to the currently predicted suitable habitat area, future prediction model for 2050 showed decrease of habitat area by 3.54%. annual precipitation (bio 12) and minimum temperature of coldest month (bio 6) were the strongest predictors for the distribution of V. tessellata with 42.8% and 13.6%, respectively.

During the present study, the distribution and phytosociological association of orchids with higher plants were determined. All the orchid species were noted down from each site with the association of the phorophytic plants. Altogether, 43 orchid species along with 52 tree species were recorded from all the six studied sites. The more number of species were presently observed in the Gurguria region followed by Chahala. Amongst these phorophytic plants, only 9 tree species were mostly associated with epiphytic orchids which gave shelter and shade to these plants. The girth class relations to the orchid species were monitored at each site; these revealed that GBH [Girth at Breast Height (61 cm - 150 cm)] were always preferable for orchids, because the dead cell mass and the dust particles along with some gum secreted by the phorophyte was always deposited on that and this might be the reason for growth of moss and epiphytic orchids on that girth class. The most favourable locality of the ground orchids was sandy soil along with high humidity. Furthermore, fragmentation of habitats, removal of key species critical to the continued existence of ecosystems, increased susceptibility to fire threats, pollinator decline, and introduction of feral animals were also documented to result in drastic losses in orchid populations and diversity. However, detailed information on orchid population and biology is needed to assist conservationists so as to develop an appropriate management strategies in highly fragmented and altered landscapes. Presently, the main approach was to find out the ecological stress related to girth class preference of phorophytes on orchid flora of Similipal Biosphere Reserve and their subsequent management, in future.

Amongst the endemic orchids of India, 25 taxa have their distribution in Odisha. Out of these, 11 taxa are confined to Odisha. Enumeration of these taxa is provided in this paper. Status of two taxa has been raised from variety to subspecies.

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