关键词: 马来西亚, 豆科, 花粉形态, 外壁纹饰, 光学显微镜, 扫描电子显微镜

Abstract: Many Leguminosae species are important tree components in the tropical rainforests of Southeast Asia, the pollen types of which are of great significance for accurate reconstruction of past plant communities. Here, we used light microscopy (LM)  and scanning electron microscopy (SEM) to observe and describe pollen morphology of 26 legume species from 21 genera, which are widely distributed in Malaysia. The morphological characteristics of these pollens are diverse, including triporate, syncolporate, tricolporate, 9-colporate, and Polyad. Tricolporate type was the most common one (65%). The pollen shape was mainly spheroidal, others were prolate subprolate and oblate spheroid. The largest size of pollen was observed inAlbizzia(89.8 μm×98.7 μm) and the smallest one was the Ormosia bancana (18.1 μm×19.2 μm). The pollens with polar axis length in the range of 25-50 μm accounted for 77% of the total. Exine ornamentation was mainly reticulate (53.8%), but also included verrucate and psilate. Based on SEM observation and evidence in the literature, Leguminosae pollen can be better identified to genus level according to the different characteristics of the size, orientation and aperture of tricolporate type pollen. We found significant morphological differences among subfamilies (Caesalpinioideae, Mimosoideae, and Papilionoideae). With reference to the habitats of parent plants, we discussed their implication to indicate different plant communities and provided reference for the reconstruction of palaeovegetation, palaeoenvironment and palaeoclimate based on fossil pollen data.

Key words: Malaysia, Leguminosae, pollen morphology, exine ornamentation, light microscopy, scanning electron microscopy.