Paul J. A. KEßLER

Effects of fire and selective logging on the tree species composition of lowland dipterocarp forest in East Kalimantan, Indonesia

Tree species composition (diameter at breast height (dbh) ≥ 10 cm) was studied in primary, selectively logged and heavily burnt forests in East Kalimantan, Indonesia. The number of trees, tree species, and the Fisherss-α diversity index were determined for the first 15 years (burnt forest) and 25 years (selectively logged forest) after disturbance. Additionally the population structure of six common and typical Macaranga pioneer tree species was compared through time between selectively logged, burnt and primary forest. Both selectively logged and burnt forest showed a significant reduction in number of trees and tree species per surface area directly after disturbance. Fire especially affected dominant tree species, while for selective logging the opposite was observed. In selectively logged forest the number of trees, tree species and the Fisherss-α index reached pre-disturbance levels within c. 15 years. For burnt forest, only the number of trees recovered to pre-disturbance levels. The number of tree species stayed constant after disturbance, while the Fisherss-α index decreased. The six studied Macaranga pioneer tree species seedlings were present in all forest types. Their density seems to be unrelated to light levels in the forest understorey but strongly related to the number of mature parent trees. Their sapling densities were strongly related to light levels in the forest understorey. The studied Macaranga species formed an important part of both under- and over-storey in burnt forest 15 years after disturbance, while they were almost absent in the understorey and only moderately common in the overstorey of selectively logged forest.

Identifying clades in Asian Annonaceae: monophyletic genera in the polyphyletic Miliuseae

The tribe Miliuseae (Annonaceae) comprises six genera distributed in Asia: Alphonsea, Mezzettia, Miliusa, Orophea, Platymitra, and Phoenicanthus. A phylogenetic study to investigate the putative monophyly of the tribe and the intergeneric relationships is presented here. Nucleotide sequences of the plastid gene rbcL, trnL intron, and trnL-trnF intergenic spacer were analyzed from 114 Annonaceae taxa, including 24 Miliuseae species and two outgroups using maximum parsimony and Bayesian inference. The two data sets (rbcL and the trnL-trnF regions) were analyzed separately and in combination. Miliuseae were found to be polyphyletic due to the position of Mezzettia and are part of a large, predominantly Asian and Central-American clade (miliusoid clade). Although intergeneric relationships were poorly resolved, all genera, except Polyalthia, were monophyletic, supporting previous generic delimitation based on morphology. A group of three Polyalthia species seems the most likely sister group of Miliusa. Several infrageneric groups of Miliusa, Orophea, and Polyalthia are supported by both molecular and morphological data. No morphological synapomorphies have yet been found for the miliusoid clade. Molecular clades within the miliusoid clade, however, can be characterized by size and the shape of the outer petals, number of ovules per carpel, and the size of the fruits.

Macaranga and Mallotus species (Euphorbiaceae) as indicators for disturbance in the mixed lowland dipterocarp forest of East Kalimantan (Indonesia)

The indicator value (IV) of Macarangaand Mallotus species (Euphorbiaceae) for different types of disturbance in lowland dipterocarp forest was assessed by counting and identifying all individuals of species of these genera taller than 30 cm in 45 (10 m × 300 m) plots at nine locations. Twelve Macarangaand nine Mallotus species were found. The main forest disturbance types (primary forest, secondary forest, selectively logged forest, forest burned once, and repeatedly burned forest used for shifting-cultivation) each had their own set of indicator species. The level of disturbance in the forest types was assessed by measuring nine forest structural parameters. The occurrence of Macarangaand Mallotusspecies was closely related to the level of disturbance in a forest. Most Macarangaspecies were characteristic of high disturbance levels, while most Mallotusspecies preferred intermediate to low levels of disturbance. However, both genera had species at both disturbance extremes. Using multiple regression analysis, combinations of Macarangaand Mallotus species were formed and used to predict the separate forest structural parameters and the general level of disturbance of a forest. The Macaranga and Mallotus species could be grouped into (1) primary forest ‘remnant’ species; (2) generalist pioneer species; and (3) high disturbance pioneer species.

Reassignment of Six Polyalthia Species to the New Genus Maasia (Annonaceae): Molecular and Morphological Congruence

Abstract Recently published molecular phylogenies of the Annonaceae have confirmed the long-held hypothesis that the large paleotropical genus Polyalthia is polyphyletic. Species previously assigned to Polyalthia are now known to belong to up to six distinct, generally well-supported clades. Three members of a group of six species previously referred to as the Polyalthia hypoleuca complex form a monophyletic group (with 99% bootstrap support) that is only distantly related to the other species of Polyalthia sampled. Putative morphological synapomorphies are assessed, and justification provided for validating a new generic name, Maasia . Six species names in the Polyalthia hypoleuca complex are accordingly transferred to Maasia: M. discolor, M. glauca, M. hypoleuca, M. multinervis, M. ovalifolia, and M. sumatrana .

Further fragmentation of the polyphyletic genus Polyalthia (Annonaceae): molecular phylogenetic support for a broader delimitation of Marsypopetalum

The species-rich genus Polyalthia has previously been shown to be highly polyphyletic, with species represented in at least five different clades. The Polyalthia species that are associated with Marsypopetalum and Trivalvaria (as revealed either by previous phylogenetic studies or inferred on the basis of comparative morphology) were included in a molecular phylogenetic study based on three chloroplast DNA regions (matK, rbcL and trnL-F). Maximum parsimony, maximum likelihood and Bayesian analyses consistently revealed that several Polyalthia species form a well-supported clade with Marsypopetalum pallidum, and that this clade is sister to Trivalvaria. Diagnostic morphological characters for the clades are re-evaluated and shown to be congruent with the molecular phylogeny. Five Polyalthia species (P. crassa, P. littoralis, P. lucida, P. modesta and P. tristis) are accordingly transferred to Marsypopetalum.

Reassessing the Generic Status of Petalolophus (Annonaceae): Evidence for the Evolution of a Distinct Sapromyophilous Lineage within Pseuduvaria

Abstract The genus Petalolophus (Annonaceae) consists of only one species, P. megalopus, which is characterised by the possession of elaborate perianth wings that extend abaxially from the midrib of the inner petals. Recently published molecular phylogenetic data suggest that Petalolophus is congeneric with Pseuduvaria. Morphological and anatomical characteristics of both genera are critically re-examined and shown to support this conclusion: Petalolophus shares numerous characteristics in common with Pseuduvaria (particularly species from New Guinea) and it is only the autapomorphic possession of extended perianth wings that currently distinguish Petalolophus from Pseuduvaria. Petalolophus megalopus is accordingly formally transferred to Pseuduvaria. Field observations reveal that the flowers of Pseuduvaria megalopus are visited by flies; it is likely that pollination is sapromyophilous, and that the inner petal wings attract flies by mimicking carrion.