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Numerous Australian terrestrial orchid species in the genus Diuris may be pollinated by food source mimicry. In our field studies, direct observations of orchid?pollinator interactions were rare, but native bees were frequently captured carrying orchid pollinaria, or pollinaria remnants. Sometimes, pollinaria remnants were minimal and included only the viscidium, a sticky pad that was often highly persistent. Confirmation of such tissue as being of orchid source, and attributing them to a particular species can aid pollination studies. DNA-based methods that may identify more or less intact orchid pollinaria are available, but extremely small and degraded samples can pose technical challenges. We have developed an AFLP protocol for such difficult samples that offers some significant advantages over direct PCR-based analysis. We simulated AFLP profiling of very low-DNA samples using DNA template from serial dilutions. A DNA sample range from 6.4 picograms to at least as high as 100 nanograms (15500-fold range) all yielded AFLP fingerprints. The practical application of this inherent sensitivity of AFLP is demonstrated by the identification of remnants of orchid pollinaria sampled from bees, presented here as a case study. It is expected that this approach will find many applications where sample DNA is limiting, or possibly where pollen of similar appearance may comprise species mixtures.

The creation of Australia's Virtual Herbarium forced the Australian plant systematics community to find a mechanism for deciding between alternative taxonomies. Following a workshop on the Orchidaceae and the publication of some simple draft guidelines, a set of ?rules of thumb' are presented here that we believe represent the view of most practising systematists. Not everyone will agree, and we have provided alternative views where possible. We include the need for monophyletic taxa, minimising taxonomic change, understanding that some taxa have strong ?interest groups', making it clear that ?preferred name' does not necessarily imply ?best name' on all criteria, avoiding epithets used in possible congeners, and the concept of ?majority rules' when states and territories have differing views.

Crisp, M. D., Gilmore, S. R. & Weston, P. H.: Phylogenetic relationships of two anomalous species of Pultenaea (Fabaceae: Mirbelieae),and description of a new genus. – Taxon 48: 701‐714. 1999. – ISSN 0040‐0262. The phytogeny of genera related to Pultenaeawas investigated using three independent data sets: morphology and nucleotide sequences of non‐coding DNA from the nucleus (ITS) and the chloroplast (trnL‐F). Elucidating the relationships of two species anomalous in Pultenaea – P. neurocalyxand P. selaginoides –was the principal question. Despite some incongruence among the data sets, P. neurocalyxis unambiguously placed with Eutaxia,but its formal taxonomic placement – either as a species of Eutaxiaor as a monotypic new genus –is left undecided pending a species‐level analysis of that group. The precise phylogenetic position of P. selaginoidesis not clear, due to incongruence between the ITS and trnL‐F data sets. Its most likely relationship is with Almaleea,as indicated by both morphology (weakly) and trnL‐F (strongly). To accommodate this species, a unispecific new genus, Stonesiella,is created, diagnosed by characters of the inflorescence and bracts, and the absence of all synapomorphies of the other Pultenaea‐group genera. The appropriateness of recognising monotypic genera is discussed. Monophyly of Pultenaeas.str. (excluding P. selaginoidesand P. neurocalyx) is supported equivocally.

Numerous Australian terrestrial orchid species in the genus Diuris may be pollinated by food source mimicry. In our field studies, direct observations of orchid.pollinator interactions were rare, but native bees were frequently captured carrying orchid pollinaria, or pollinaria remnants. Sometimes, pollinaria remnants were minimal and included only the viscidium, a sticky pad that was often highly persistent. Confirmation of such tissue as being of orchid source, and attributing them to a particular species can aid pollination studies. DNA-based methods that may identify more or less intact orchid pollinaria are available, but extremely small and degraded samples can pose technical challenges. We have developed an AFLP protocol for such difficult samples that offers some significant advantages over direct PCR-based analysis. We simulated AFLP profiling of very low-DNA samples using DNA template from serial dilutions. A DNA sample range from 6.4 picograms to at least as high as 100 nanograms (15500-fold range) all yielded AFLP fingerprints. The practical application of this inherent sensitivity of AFLP is demonstrated by the identification of remnants of orchid pollinaria sampled from bees, presented here as a case study. It is expected that this approach will find many applications where sample DNA is limiting, or possibly where pollen of similar appearance may comprise species mixtures.

In this empirical study of species boundaries in a small genus of plants, we take the view that species are ambivalent; some appear to be monophyletic taxa, but some lack autapomorphies and are metataxa. As an operational definition, we recognized species from differentiated clusters in phenetic space whose distinctness was assumed to be the manifestation of underlying, fixed, and qualitative differences following speciation. These units were considered appropriate as terminals for phylogenetic reconstruction. The appropriateness of different phenetic methods in relation to models of infraspecific geographic variation and evolution is discussed. At the population level, ordination was more suitable than either cladistics or cluster analysis because it does not impose a rigidly hierarchical pattern on the data when none is expected. Variation among populations of Telopea was investigated by phenetic analysis of adult morphology. The main questions were whether the conventional distinction of T. mongaensis Cheel from T. oreades F. Muell. could be justified and whether disjunct populations referred to T. speciosissima (Smith) R.Br. in the Gibraltar Range, northern New South Wales, constituted a distinguishable taxon. The Gibraltar Range waratahs were distinguishable from typical T. speciosissima by their abundant ferruginous hairs, elliptic to obovate leaves, and numerous teeth along the lower half of the leaf margin; we propose recognizing them as a new species. Ordination analysis revealed a strong ontogenetic pattern within populations of T. speciosissima sensu lato, indicating that adult plants were retaining lobed intermediate leaves. Canonical variate analysis confirmed that this pattern was distinguishable from the between-population geographic pattern, but cluster analysis confounded the geographic and ontogenetic patterns. Conventional recognition of T. oreades and T. mongaensis as distinct species was supported by both ordination and cluster analysis. One population was mixed, with little evidence of hybridization between the sympatric species. Canonical variate analysis of populations was confounded by the heterogeneous population.

Although congruence among multiple taxa is accepted as the basis of the cladistic approach to biogeography, seldom has congruence been tested for patterns within continents. Moreover, contiguous land areas are subject to confounding factors that might lead to incongruence, and areas of endemism are difficult to define. Most previous studies have analyzed single taxa and therefore could not test for congruence. Here, we report the first cladistic biogeographic analysis of multiple plant taxa (11 angiosperm groups) within continental Australasia. We have used Pages (1994, Syst. Biol. 43:58–77) new mapping method implemented in his program COMPONENT 2.0, minimizing the optimality criterion “leaves added,” which is the number of terminal branches that need to be added to reconcile all input cladograms with the general area cladogram. A randomization test showed significant congruence, and a jackknife test indicated which parts of the general area pattern are robust. Conflicting patterns shown by widespread species may have been influenced by recent range expansions. At least two independent histories are postulated for taxa endemic to the tropics. One appears as a close relationship between the monsoon tropical areas, including southern New Guinea, and the other is a track (a group of areas with a common history) of successive differentiation along the east and south coasts. The Australian wet tropics (the Atherton area), although geographically proximate to the monsoon tropics, are part of the east coast track. Tasmania shows a very early vicariance from the rest of the continent, and the central arid areas appear related to adjacent coastal areas rather than to each other (contra Cracraft, 1991, Aust. Syst. Bot. 4:211–227). The postulated exchange of taxa with southeast Asia following late Miocene contact was not tested because of a lack of suitable taxon cladograms.