Ericaceae in Malesia: vicariance biogeography, terrane tectonics and ecology

Abstract

Heads, Michael (Science Faculty, University of Goroka, PO Box 1078, Goroka, Papua New Guinea. Current address: Biology Department, University of the South Pacific, P.O. Box 1168 2003. Ericaceae in Malesia: vicariance biogeography, terrane tectonics and ecology. Telopea 10(1): 311-449. The Ericaceae are cosmopolitan but the main clades have well-marked centres of diversity and endemism in different parts of the world. Erica and its relatives, the heaths, are mainly in South Africa, while their sister group, Rhododendron and relatives, has centres of diversity in N Burma/SW China and New Guinea, giving an Indian Ocean affinity. The Vaccinioideae are largely Pacific-based, and epacrids are mainly in Australasia. The different centres, and trans-Indian, trans-Pacific and trans-Atlantic Ocean disjunctions all indicate origin by vicariance. The different main massings are reflected in the different distributions of the subfamilies within Malesia. With respect to plant architecture, in Rhododendron inflorescence bracts and leaves are very different. Erica and relatives with the 'ericoid' habit have similar leaves and bracts, and the individual plants may be homologous with inflorescences of Rhododendron. Furthermore, in the ericoids the 'inflorescence-plant' has also been largely sterilised, leaving shoots with mainly just bracts, and flowers restricted to distal parts of the shoot. The epacrids are also 'inflorescence-plants' with foliage comprised of 'bracts', but their sister group, the Vaccinioideae, have dimorphic foliage (leaves and bracts). In Malesian Ericaceae, the four large genera and the family as a whole have most species in the 1500-2000 m altitudinal belt, lower than is often thought and within the range of sweet potato cultivation. The same belt is also most diverse for ferns, birds-of-paradise and bowerbirds. Distribution maps of Malesian Ericaceae are presented, with related species indicated. Concentric patterns of distribution are frequent and could be attributable to evolution around shrinking seas. In New Guinea the main axial range is a composite structure, with the southern part formed by the old Australian craton and the northern and eastern parts formed from 32 tectonostratigraphic terranes or microplates. These formed independently and then docked with each other and the craton. The tectonic boundary between the craton and the accreted terranes is also an important biogeographic boundary. Many taxa have distributions linking different accreted terranes but are not on the craton. Movement and integration of island arcs and more substantial terranes has led to complex patterns of disjunction throughout Malesia, but there is an underlying parallel-arc structure, seen clearly in New Guinea. The tectonic provinces in Borneo are also reflected in the two main biogeographic tracks: Kuching--Kinabalu and Kutei Mts./Mt. Kemul-Kinabalu, the Lupar River boundary and the Meratus Mts. centre. The islands of the Riouw Pocket (Corner 1978a) are notably surrounded by many groups which are absent th...

Anatomy and Morphological Study of Mentigi Gunung (Vaccinium varingiaefolium (Blume) Miq.) in Area of Mount Batok-Indonesia

“…In some area mount in Java this plant can be found as shrub and dwarves [5,6] and dwarf or little tree in the area near caldera [5] or sulphur vent or open area, extremely stony and rather dry places and grow as tree in rich humus area. It will be smaller in area with wind exposed [2].…”

“…This plant is fire resistant, its stem is sprouted and is holding on volcanic mountain which still explode [2]. This plant has spesific sweet odor, we suggest it came from nectarium and osmophore [3].…”

“…V. varingiaefolium has a tap root. As one of the Malesian Ericacea according to the Heads [2] root particularly in crater fields and near solfataras, is very horizontal, and roots may attain large dimensions in such places. This is, of course, common to all plants growing on sterile, rocky, impervious or badly drained soils.…”

“…This is, of course, common to all plants growing on sterile, rocky, impervious or badly drained soils. Such roots also have a distinctly corky bark [2]. Based on that condition the root of V. varingiaefolium grows lengthwise according to its uses who absorb the water.…”

“…In Java, this plant grows well in the area closed to sulphur vents or volcano region [1], such as Mount Batok. Therefore, it dominates the subalpine area of Mount Batok and Bromo (above 1 800 m to 2 000 m) [1,2]. There is a rare study of this plant.…”