**4. Plant biodiversity in IHR**

In angiosperms, about 10,452 species belong to 2302 genera and 232 families and in gymnosperms, 51 species belong to 20 genera and 8 families are reported from the IHR, Nepal and Bhutan [22]. About 3160 species of vascular plants in the Himalayan region are endemic. The IHR represents 18,940 species of plants, among these 8500 species (40% endemics) characterized by angiosperms; 44 (15.91% endemics) by gymnosperms, 600 (25% endemics) of pteridophytes; 1737 (32.53% endemics) of bryophytes; 1159 (11.22% endemics) of lichens and 6900 (27.39% endemics) of fungi. In angiosperms overall, 6745 species of 225 families, belonging to 1768 genera have been noticed from the Trans, North West, and Western Himalayas. Among that, 604 were tree species, 1049 shrubs and herbs are 5092 [21]. About 3984 species of angiosperms and 21 species of gymnosperms are reported from Arunachal Pradesh; From Assam, 3010 species of angiosperms and 7 species of gymnosperms; In Manipur, 2376 angiosperms species and 5 of gymnosperms; from Meghalaya, angiosperms 1886 and 6 species in gymnosperms; 2141 angiosperms and 6 of gymnosperms from Mizoram;

### *Biodiversity Conservation of Western Himalayas: A Pluralistic Approach DOI: http://dx.doi.org/10.5772/intechopen.107075*

In Nagaland, 2431 angiosperms and 9 of gymnosperms species; 1463 species in angiosperms and 13 of gymnosperms from Tripura, and 4458 species of angiosperms from Sikkim were recorded [23].

The gymnosperms group is represented by the families Cupressaceae, Cycadaceae, Ephedraceae, Ginkgoaceae, Pinaceae, Podocarpaceae, Taxaceae, and Taxodiaceae in the IHR [22]. The angiosperms are the biggest collection of plant species and consist of the families Acanthaceae, Apiaceae, Asteraceae, Brassicaceae, Fabaceae, Euphorbiaceae, Lamiaceae, Liliaceae, Orchidaceae, Poaceae, Polygonaceae, Rosaceae, Rubiaceae, Scrophulariaceae, etc. Some monotypic families represented only by single species are Actinidiaceae, Adoxaceae, Casuarinaceae, Biebersteiniaceae, Calycanthaceae, Cannaceae, Caricaceae, Ceratophyllaceae, Circaesteraceae, Clusiaceae, Coriariaceae, Daphniphyllaceae, Datiscaceae, Dipterocarpaceae, Droseraceae, Hippuridaceae, Icacinaceae, Iteaceae, Lardizabalaceae, Leeaceae, Marantaceae, Martyniaceae, Melianthaceae, Moringaceae, Myricaceae, Ochnaceae, Paeoniaceae, Platanaceae, Plumbaginaceae, Podophyllaceae, Podostemaceae, Proteaceae, Punicaceae, Rhizophoraceae, Saurauiaceae, Sonneratiaceae, Saururaceae, Sphenocleaceae, Stylidiaceae, Torricelliaceae, Trillidiaceae, Tropaeolaceae, Zannichelliaceae, etc. The dominating genera in Trans, North West, and West Himalaya are, *Carex, Taraxacum*, *Potentilla*, *Astragalus*, *Saxifraga*, *Cotoneaster, Artemisia*, *Cyperus, Polygonum, Corydalis, Berberis, Euphorbia, Silene, Poa, Primula, Pedicularis, Nepeta, Impatiens, Ranunculus, Persicaria, Veronica, Allium, Rubus, Ficus,* etc. [21].

In medicinal plants, a total of 1748 species belonging to 915 genera and 223 families are found in the IHR (**Table 1**). The families that signify the greatest number of medicinal plants in descending orders are, Asteraceae, Fabaceae, Lamiaceae, Rubiaceae, Euphorbiaceae, Ranunculaceae, Rosaceae, Poaceae, Orchidaceae, Polygonaceae, and Gentianaceae, respectively. The medicinal plant-rich genera are *Polygonum*, *Euphorbia*, *Piper*, *Ficus*, *Aconitum* and *Swertia*, *Artemisia*, *Solanum, Berberis, Desmodium,* and *Allium,* and *Saussurea*, respectively. A total of 675 wild edible plants representing 384 genera and 149 families are known in IHR. Of these, 285 species are herbs, 172 species of shrubs, 197 species of trees, 12 species of pteridophytes, 07 species of fungi, and 02 species of lichens (**Figure 2**).
