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Abstract: The present paper reports on palynology and pollination ecology of eight taxa of Amorphophallus from North Western Ghats (NWGS) and Konkan region of India. Out of ten known pollen exine ornamentations of the genus, six are represented – psilate, striate, fossulate, verrucate, scabrate and the new type ‘pseudofossulate’ of Amorphophallus commutatus var. wayanadensis. These diverse pollen exine ornamentations can be utilized as an important taxonomic tool to distinguish taxa and also to resolve taxonomic problems (A. commutatus complex). The pollen of all eight taxa had retained their sculptured surface (exine ornamenatation type) after acetolysis. This clearly demonstrates that these taxa do not show susceptibility to the conventional acetolysis technique as reported earlier. The present study also highlights the importance of pollen surface morphology concerning phytogeography of the genus. Observation of pollination ecology of the studied Amorphophallus taxa reveals that all are mostly visited by beetles (Bostrichidae, Cetoniidae, Hybosoridae, Lyctidae, Nitidulidae, Rutelinae, Scarabaeidae, Staphylinidae), followed by flies (Drosophilidae, Muscidae), bees (Apidae: Trigone), ants (Formicidae, Dolichoderinae) and cockroaches (Blaberidae/Panesthiinae). The beetle families Bostrichidae, Lyctidae and Rutelinae, ant families Formicidae and Dolichoderinae and the cockroach family Blaberidae/Panesthiinae are for the first time reported as visitors in the genus Amorphophallus. Most of the taxa display features characteristic of cantharophily (beetle pollination) except A. commutatus var. commutatus and A. commutatus var. wayanadensis, where Trigona bees are the actual pollinators. The beetles (Cetoniidae, Nitidulidae, Scarabaeidae) and bees (Apidae: Trigona) are the real pollinators for the Amorphophallus species of NWGS and Konkan while rest of the insects are mere visitors for alimentary/food resources (staminode flowers, stigmatic fluid, pollen, appendix surface, appendix exudates) and using the inflorescences as mating and egg laying sites. Species belonging to the section Rhaphiophallus (Amorphophallus konkanensis and Amorphophallus sylvaticus) are pollinated by Epuraea – Haptoncurina sp. (Nitidulidae) beetles only. Generally, the species of Amorphophallus in NWGS and Konkan region with short flowering peduncle are always pollinated by dung beetles or scarabs while species bearing a long flowering peduncle are usually pollinated by Epuraea – Haptoncurina sp. (Nitidulidae) beetles and Trigona bees. Based on the comparative observations, five different phases of insect trapping in Amorphophallus taxa are characterized, focusing on the intricacies of pollination strategies of various pollinators. [Copyright &y& Elsevier]

Abstract: The palaeobotanical and palynological data along with physical proxies obtained from Konkan, western India, have been addressed while ascertaining the vegetation response to monsoon variations since Late Pleistocene (∼53,000 yrs BP). The retrieved plant fossil assemblage, being a sensitive indicator of climate changes, has important implications in palaeoclimate study of the Late Pleistocene as it is the first of its kind in the entire 7500 km long coastline of India. The plant fossil assemblage of the lacustrine sediments forms potential evidence for the prevalence of wet evergreen forest in the Late Pleistocene (∼44,000 yrs BP). This scenario was attributed to prevalence of an extended period of rainfall of both the Southwest (SW) and Northeast (NE) monsoon in Konkan, although the Indian subcontinent was under the influence of active tectonic processes. Numerous fossil plant taxa are now confined to freshwater Myristica swamps of Southeast Asia in general and that of southwestern India in particular suggesting that these areas maintain a similar monsoon trend to that existing prior to 44,000 yrs BP. On the other hand, the NE monsoon did not reappear during the Early Holocene, when the SW monsoon became strong along the Konkan coast. Many of the plant species of the fossil assemblage have been displaced from Konkan as a response to weakening of the monsoons since the Late Pleistocene and towards the Last Glacial Maximum (LGM). The aridity/reduced rainfall since Late Pleistocene, including the LGM, and limited terrestrial accumulation in the Early Holocene suggests an ecological shift and subsequent replacement of evergreen forest cover and a possible break in sedimentation. Palynological evidence of the Late Holocene (<3000 yrs BP) fluvio-lacustrine sediments reveals that the evergreen forest could not reappear/rejuvenate in Konkan due to such climatic stress, in contrast to southwestern India and Sri Lanka where extended rainfall was still prevalent. The hypothesis of an extended period of monsoonal rains prior to 44,000 yrs BP in the present humid tropical parts of Konkan holds significance, as data on paleosols and vertebrate fossils from the semi-arid/arid parts of western India indicate relatively wet climate and wetland flood plains. [Copyright &y& Elsevier]