Andamanese Mangrove Forest
This BioProvince includes some of the most luxuriant mangrove forests on the planet supporting about 60 mangrove species. The most important of these are Avicennia officinalis, Bruguiera gymnorhiza, B. parviflora, Ceriops tagol, R. mucronata, Rhizophora apiculata, Sonneratia alba and S. caseolaris, while some of the less common species are Excoecaria agollocha, and Lumnitzera littorea with its bright scarlet flowers. In the areas of transition between the mangrove forest and the inner littoral forest species such as Brownlowia lanceolata, Cerbera manghas, Derris trifoliata, Heritiera littoralis and Scyphiphora hydrophyllacea occur. While most palms are unable to tolerate the brackish conditions in mangrove swamps, two species, Nipa fructicans and Phoenix paludosa, are exceptions to the rule, and can often give these swamps a very picturesque appearance, especially the former with its crown of foliage held just above the water mark.
Andamanese Evergreen Rainforest
Confined mainly to lower elevations these rich forests typically show three stories. The upper story or canopy is formed by gigantic trees reaching heights of up to 60 m, and includes endemic species such as Canarium mani (Burseraceae), Dipterocarpus kerrii (Dipterocarpaceae), Hopea andamanica (Dipterocarpaceae), Myristica andamanica (Myristicaceae), Planchonia andamanica (Lecythidaceae), Xanthophyllum andamanicum (Polygalaceae) as well as Dipterocarpus incanus, Hopea odorata, Sideroxylon longipetiolatum, while on the Nicobars these would include the endemic Bentinckia nicobarica (Arecaceae). Below the canopy is a tier of trees whose heights vary between 20-30 m. Prominent among these are Dillenia pentagyna, Duabanga sonneratioides, Litsaea panamonja, Myristica irya, Pisonia excelsa, Powetia pinnata, and the endemic Ailanthus kurzii (Simaroubaceae) and Lagerstroemia hypoleuca (Lythraceae). The lower most tree layer includes various shade tolerant species such as Fragraea morindaefolia, Macaranga tanarius, Mitrephora prainii, the endemic Drypetes andamanica (Putranjivaceae) and Orophea hexandra (Annonaceae), and the near endemic Garcinia andamanica (Clusiaceae), Pandanus andamanensium (Pandanaceae) and Talauma andamanica (Magnoliaceae). On the Nicobars these smaller trees typically include the endemic or near endemic Apodytes andamanica (Icacinaceae) and Ochna andamanica (Ochnaceae). Important species in the shrub layer are Areca triandra, Clerodendrum viscosum, Clinogyne grandis, Leea indica, the endemic taxa Glycosmis pentaphylla var. andamanensis (Rutaceae), Maesa andamanica (Myrsinaceae) and Peristrophe andamanica (Acanthaceae),and the near endemic Polyalthia andamanica (Annonaceae). Most of the arborescent species throughout these forests are heavily laden with woody climbers including the ancient Gnetum scandens, the endemic Mezoneuron andamanicum (Fabaceae) and the endemic climbing bamboo Dinochloa andamanica (Poaceae). There are also many epiphytic species especially ferns and orchids. On the Nicobars these include the endemic orchid Trichoglottis quadricornuta (Orchidaceae). Also endemic to these forests is the magnificent ground orchid Phalaenopsis speciosa (Orchidaceae). Finally, an unusual feature of these tropical, evergreen forests is the lack of tree ferns.
The Nicobars have a type of evergreen forest occurring on raised coral reefs. These differ in character from the more inland forests. The tree species typically include the endemic Orophaea katschallica (Annonaceae) and the near endemic Aglaia andamanica (Meliaceae) and Apodytes andamanica (Icacinaceae), while the shrubby growth includes the near endemic Psychotria andamanica and P. nicobarica (Rubiaceae).
Andamanese Deciduous Forest
These forests, which include trees that shed their leaves (either fully or partially) during the dry season, are mainly confined to undulating ground in the hills where the soil in comparatively dry. One of the most conspicuous and elegant trees is Pterocarpus dalbergioides (sometimes known as the Andaman red wood) can reach heights of 45 m. Associated common trees include Albizzia lebbeck, Arthrocarpus chaplasha, Canarium euphyllum, Diploknema butyracea, Parisha insignis, Pterocymbium tinctorium, Terminalia procera, Tetrameles nodiflorum and the endemic Ailanthes kurzii (Simaroubaceae). Some of these giant trees, such as Pterocarpus dalbergioides and Tetrameles nodiflorum, have huge buttressed roots. Below the canopy lies a middle striatum of trees growing to heights of up to 30m. These include Lannea grandis, Sageraea elliptica, Sterculia villosa, Semecarpus kursii, Diosporos pyrrhocarpus, Zanthoxylum budrunga, Garruga pinnata, Cratoxylon formosum, Pterospermum aceroides and the endemic Miliusa tectona (Annonaceae), while below this are a series of smaller trees such as Atlantia monophylla, Cleidon javonicum, Gelonium bafarium, Grewia disperma, Licuala spinosa, Limonia alata, Linociera terniflora, Ochna wallichii and Streblus asper. The undergrowth is much better developed than in the evergreen forest, comprising various shrubby species such as Actephila excelsa, Bridelia griffithii, Calamus viminalis, Glycosmis pentaphylla, Ixora grandiflorus, Licuala peltata, Malotus acuminatus and Rinorea bengalensis, All of these various layers within the forest are connected by an array of climbers and stragglers. Common amongst these are Acacia pennata, Delima sarmentosa, Sphenodesme unguiculata, Thunbergia laurifolia, Ventilago madraspatana and the endemic or near endemic Calamus andamanicus (Arecaceae) and Plecospermum andamanicum (Apiaceae). The herbaceous vegetation is composed largely of grasses such as Centotheca lappccea, Crytococcum exyphyllum, Dichanthium annulatum, Echinochloa crusgalli, and Paspalum conjugatum, together with a few herbs like Alysicarpus vaginalis, Nelsonia campestris and Peperomia pellucida.
Other species endemic or near endemic to the Andamanese BioProvince include Aglaia andamanica, Amoora manii, Aporosa glabrifolia, Ardisia andamanica, Aspidiopterys andamanica, Atalantia macrophylla, Blachia andamanica, Chailletia andamanica, Crateava macrophylla, Cryptocarya andamanica, Dendrobium tenuicaule, Dichapetalum andamanicum, Dichopetalum gelanoides, Dillenia andamanica, Dinochloa andamanica, Diplospora andamanica, Dixochloa andamanica, Dysoxylum andamanicum, Eulopia andamanensis, Garcrinia jelinekii, Ginalloa andamanica, Glochidion andamanica, Gouania andamanica, Habenaria andamanica, Hedyotis andamanica, Hippocratea andamanica, Hippocratea nicobarica, Jasminium andamanica, Lasianthus andamanicus, Linociera parkinsonii, Linostoma andamanica, Litsea leiantha, Mangifera nicobarica, Mesua manii, Mallotus andamanicus, Mangifera andamanica, Memecylon andamanicum, Mimusops andamanesis, Modecca nicobarica, Mussaenda jelinekii, Neolitsia andamanica, Orophaea katschallica, Otanthera nicobarensis, Polyalthia parkinsonii, Prismatomeria andamanica, Pubistylis andamanensis, Sagaraea andamanica, Scutellaria andamanica, Stephenia andamanica, Strobilanthus andamanesis, Strobilanthes glandulosus, Syzygium andamanicum, Taeniophyllum andamanicum, Tetrastigma andamancium, Tinospora andamanica, Trigonostemon aurantiacus, Trivalvaria dubia, Uvaria andamanica, Wendalandia andamanica and Zeuxine andamanica.
Further information required.
References
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