Selected pollen grains from tropical Hainan Island, south China: An identification key to Quaternary pollen

•Eleven pollen plates of 52 species belonging to 26 families of arboreal and liana plants are presented.•Coverage of representative pollen types identified in tropical Chinese Quaternary pollen.•Key to pollen identification with detailed descriptions and illustration.•Palaeoecological and palaeobiogeographical implication of the key pollen types.

Pollen keys are essential for accurate and consistent identification of Quaternary pollen, as well as pre-Quaternary fossil pollen, which in turn enables a better understanding of past biodiversity and vegetation changes. Here, we present a pollen key to 52 species of arboreal and liana plants from 26 families on tropical Hainan Island, covering representative pollen types identified in tropical Chinese Quaternary deposits. Such a pollen key along with detailed descriptions and illustrations should enable fossil pollen to be accurately identified. Nevertheless, the key is open for future improvement, so that pollen of other plants from the same study area can be accommodated when specimens become available. In their present state they should, however, aid palynological analyses of Quaternary deposits, particularly in tropical south China. Pollen identification as well as the palaeoecological and palaeobiogeographical significance of the key representative communities along the altitudinal gradient in our study area (i.e., coastal mangroves, tropical rainforest and montane rainforest) are also discussed in this paper.