Murray J. Henwood

A multi-locus molecular phylogeny of the Lepidoziaceae: Laying the foundations for a stable classification

The Lepidoziaceae, with over 700 species in 30 genera, is one of the largest leafy liverwort families. Despite receiving considerable attention, the composition of subfamilies and genera remains unsatisfactorily resolved. In this study, 10 loci (one nuclear 26S, two mitochondrial nad1 and rps3, and seven chloroplast atpB, psbA, psbT-psbH, rbcL, rps4, trnG and trnL-trnF) are used to estimate the phylogeny of 93 species of Lepidoziaceae. These molecular data provide strong evidence against the monophyly of three subfamilies; Lepidozioideae, Lembidioideae and Zoopsidoideae, and seven of the 20 sampled genera; Lepidozia, Telaranea, Kurzia, Zoopsis, Lembidium, Paracromastigum and Chloranthelia. Several robust clades are recognised that might provide the basis for a revised subfamily circumscription including a narrower circumscription of the Lepidozioideae and a more inclusive Lembidioideae. Neogrollea notabilis is returned to the Lepidoziaceae and Megalembidium insulanum is placed in the Lembidioideae.

A molecular phylogeny of the Lepidozia generic complex supports re-circumscription of the Lepidozioideae

Five molecular markers (chloroplast rbcL and trnL-trnF, mitochondrial nad5-nad4, and nuclear ITS1 and ITS2) were used to investigate membership of the Lepidoziaceae, subfamily Lepidozioideae and relationships between its constituent species. The Lepidozioideae (comprising Lepidozia, Telaranea, Kurzia, Sprucella, Psiloclada) are polyphyletic as are two of its five constituent genera (Telaranea and Kurzia). We find strong support for a monophyletic lineage comprising Lepidozia, Sprucella (nested within Lepidozia), and part of Telaranea. Within this lineage we find partial support for four main clades. Three clades of Telaranea species form consecutive sister relationships to a monophyletic Lepidozia. Relationships within Lepidozia are incompletely resolved. We provide a re-circumscription of the Lepidozioideae that excludes Kurzia, Psiloclada and elements of Telaranea.

Infrageneric phylogeny of Chloantheae (Lamiaceae) based on chloroplast ndhF and nuclear ITS sequence data

The tribe Chloantheae (Prostantheroideae, Lamiaceae) currently consists of over 100 species in nine genera, all of which are endemic to Australia. Generic delimitations were assessed using chloroplast 3′ndhF and nuclear ITS nucleotide sequence data for up to seventy species. Analyses of the two datasets, independently and in combination, used maximum parsimony and Bayesian phylogenetic inference methods. Topologies derived from each marker were broadly congruent, but better resolution and stronger branch support was achieved by combining the datasets. The monophyly of the Chloantheae was confirmed. Brachysola is sister to the rest of the tribe and Chloanthes, Cyanostegia and Dicrastylis (including Mallophora) are monophyletic. Although the species within Dicrastylis were only partially resolved, it appears likely that the current sectional classification of this genus will require revision. A clade containing Newcastelia, Physopsis and Lachnostachys (=Physopsideae) was recovered, but the topology indicates that the current generic circumscriptions need further investigation. A close relationship between Hemiphora elderi, Pityrodia bartlingii and P. uncinata was resolved and reflects their palynological and carpological similarities. The relationship between remaining species of Pityrodia was incompletely resolved.

A revision of Australian Trachymene (Apiaceae: Hydrocotyloideae)

The current use of the name Trachymene Rudge was determined in the 1930s. However a comprehensive synonymy for the numerous published names in Trachymene has not previously been compiled. All Australian species of Trachymene are treated. A nomen novum, Trachymene leptophylla J.M.Hart, is provided for the illegitimate Trachymene filiformis Steenis. In addition, two new Australian species, Trachymene umbratica J.M.Hart and Trachymene thysanocarpa J.M.Hart, are described. A new combination: Trachymene composita var. robertsonii (Domin) J.M.Hart is made and range extensions for Trachymene oleracea subsp. sedimenta Rye, Trachymene bialata (Domin) B.L.Burtt and Trachymene rotundifolia (Benth.) Maconochie are recorded. Seven lectotypes are designated. Distribution maps and a key to all Australian species of Trachymene are provided.

Molecular phylogeny and systematics of Prostanthera (Lamiaceae)

Abstract. Prostanthera is the largest genus of Lamiaceae in Australia and was last comprehensively revised in 1870. To test the classification, and the homology of the morphological characters on which it is based, we analysed nuclear (ETS) and chloroplast (trnT–F and ndhF–rpl32) sequence data for 71 species of Westringieae (Lamiaceae) in separate and combined datasets by using maximum-parsimony and Bayesian-inference methods. Results supported the monophyly of the Westringieae, but indicated that Prostanthera is paraphyletic with respect to Wrixonia, requiring the latter to be synonymised with the former. Although combinations of datasets provided some degree of infrageneric resolution within Prostanthera sensu lato, none of its sections or series could be recovered unambiguously. Prostanthera section Prostanthera and P. section Klanderia (regarded as entomophilous and ornithophilous, respectively) did not form a sister relationship, and neither could be unequivocally resolved as monophyletic. However, all species of P. section Klanderia nested within P. section Prostanthera raising the possibility that P. section Prostanthera is paraphyletic. Similarly, the phylogeny of Prostanthera based on molecular data could not be reconciled with the morphological definition of the traditionally recognised series. We recommend abandoning Bentham’s series as a means of organising morphological variation within the genus, but acknowledge that it is premature to discard Bentham’s sections. The evolutionary and systematic implications of the lack of congruence between our molecular phylogeny and morphologically defined subgeneric taxa are discussed.

Phylogenetic relationships in Loganieae (Loganiaceae) inferred from nuclear ribosomal and chloroplast DNA sequence data

Abstract. Molecular systematics has clarified the limits of Loganiaceae (Gentianales), the tribal circumscriptions and the phylogenetic relationships within the family. Loganieae includes seven genera; however, generic boundaries remain untested and intergeneric relationships are largely unknown. The chloroplast intron petD and the nuclear ribosomal ETS were sequenced for 37 ingroup accessions, including all genera of Loganieae, to infer generic and infrageneric boundaries and intergeneric relationships within the tribe. Maximum parsimony and Bayesian analyses resolved several strongly supported clades. Mitreola s. str. was placed sister to the rest of Loganieae. The south-western Australian endemic, Mitreola minima B.J.Conn, was placed sister to Mitrasacme, Schizacme and Phyllangium, rendering Mitreola polyphyletic. Mitrasacme, Logania section Logania and L. section Stomandra were each strongly supported as monophyletic, but there was no support for the monophyly of Logania. Geniostoma was paraphyletic with respect to a monophyletic Labordia. It is here recommended that Mitreola minima be afforded generic status and that the three species of Labordia used in the present study be reduced to synonymy of Geniostoma. Additional sampling is needed to clarify the relationship between Logania section Logania and L. section Stomandra and to increase support for intergeneric relationships in Loganieae.

Synopsis of the tribe Chloantheae and new nomenclatural combinations in Pityrodia s.lat. (Lamiaceae)

An overview of the tribe Chloantheae (Lamiaceae) is presented. Nomenclatural changes associated with reinstating Dasymalla Endl. and Quoya Gaudich. as distinct genera from Pityrodia s.lat. are provided. The genus Dasymalla consists of five species previously in Pityrodia, whereas seven species of the latter genus are transferred to Quoya. The circumscription of Hemiphora F.Muell. is expanded to include four species previously included in Pityrodia and Hemiphora lanata (Munir) B.J.Conn & M.J.Henwood is formally recognised as a species, based on Pityrodia exserta (Benth.) Munir var. lanata Munir. The new genus Muniria N.Streiber & B.J.Conn is described and consists of four species occurring in the Northern Territory (Australia) that were previously in Pityrodia. A summary of the diagnostic features of Dasymalla, Hemiphora, Muniria and Quoya is presented. The synapomorphies supporting the genera of ‘Physopsideae’ sensu Munir are described, whereas no synapomorphies for Newcastelia or Physopsis were found in the data. A key distinguishing the genera of the tribe is included.

Great Expectations: Correlations between Pollinator Assemblages and Floral Characters in Lamiaceae

Premise of research. Pollination syndromes are used to infer pollinators from floral attributes when field observations of floral visitors are lacking. Such inferences are often found to be incorrect or too generalized. To investigate the relationship between pollinators and observable differences in a genus of Lamiaceae with flowers that appear ornithophilous and entomophilous, we experimentally quantified floral morphology and pollinator assemblages in a phylogenetic perspective. Methodology. Floral morphology was examined using multivariate analysis of geometric morphometrics (corolla shape described by landmarks), linear dimensions, and nonmetric attributes for 17 species of Prostanthera. Pollination effectiveness was determined through censuses of floral visitors and interactions by pollinators with flowers, and multivariate statistics were used to examine correspondence between these data and nonlandmark characters. Ancestral state reconstruction was performed using geometric morphometric data and a phylogenetic tree. Pivotal results. Three floral morphologies were identified in Prostanthera, each of which was associated with a unique pollinator assemblage and corroborated by our detailed field observations. A higher abundance of bees visited flowers with the ancestral (bee) floral type, which had a long corolla, porrect adaxial lobes, and long anther appendages. Visits by birds were more frequent to the derived bird floral type, characterized by red or green flowers with larger nectar volumes, longer and narrower corollas, and a reflexed abaxial lobe. Another derived lineage attracted a higher abundance of generalist flies and beetles (beetle+fly floral type). This lineage had flowers with a shorter corolla tube, reflexed adaxial lobes, and shorter anther appendages. Conclusions. When pollinator frequency was used as a proxy for pollinator effectiveness, the correspondence between the floral types and pollinator assemblages supported traditional concepts of bird and insect pollination syndromes. Intermediates between these floral types also corresponded with phylogenetic position and pollinator assemblage. Linear measurements of floral attributes were just as reliable as landmark data in predicting pollinator assemblages. By combining a molecular phylogeny with the above data, evidence indicated that the bird and beetle+fly floral types diversified from an ancestral bee floral type, demonstrating at least one evolutionary specialization for birds, as well as another shift toward a more generalized pollination syndrome. This combination of techniques presents a potential application with which to investigate the evolution of pollination.

Molecular phylogenetics provides new insights into the systematics of Pimelea and Thecanthes (Thymelaeaceae)

Abstract. Pimelea Banks & Sol. ex Gaertn. is a genus of flowering plants comprising an estimated 90 species in Australia and ∼35 species in New Zealand. The genus is economically important, with the inflorescences of some species having floricultural applications, and the presence of toxic compounds in several species proving poisonous to livestock. Pimelea grows in a variety of habitats ranging from arid to alpine, suggesting a complicated biogeographic history. The relationships within Pimelea remain largely uncertain, despite previous attempts at clarification using molecular phylogenetics. However, it is clear that Pimelea is closely related to Thecanthes Wikstr., with the two genera comprising the subtribe Pimeleinae. We used Bayesian and maximum-likelihood phylogenetic analyses of four plastid markers (matK, rbcL, rps16, trnL–F) and one nuclear ribosomal marker (ITS) to examine the evolutionary relationships within Pimeleinae. We found strong support for the monophyly of Pimeleinae but, similar to previous studies, Pimelea was paraphyletic with respect to Thecanthes. Our results also indicated that P. longiflora R.Br. subsp. longiflora and P. longiflora subsp. eyrei (F.Muell.) Rye are best considered as distinct species. Therefore, we reduce Thecanthes to synonymy with Pimelea, making the necessary new combination Pimelea filifolia (Rye) C.S.P.Foster et M.J.Henwood (previously Thecanthes filifolia Rye), and also reinstate Pimelea eyrei F.Muell.

Actinotus helianthi Populations across a Wide Geographic Range Exhibit Different Climatic Envelopes and Complex Relationships with Plant Traits

Premise of research. Climate envelopes are generated by overlaying climate variables derived from temperature and rainfall data onto mapped geographic locations of occurrences. Typically, the species data are amalgamated into a single climate envelope, missing the opportunity to account for the potential of different environments to independently shape the functional plant trait values within populations. Here we explore how climate envelopes vary among populations and whether individuals with similar trait values are similarly matched to particular climate envelopes or to spatial layers of environmental classifications based on additional variables other than climate. Methodology. We generated climate envelopes from 35 populations of the widely distributed plant species Actinotus helianthi Labill. (Apiaceae). Populations with at least 84% similarity in their local climate were grouped by hierarchical cluster analysis. We then tested whether the similar climate envelopes would covary with populations of plants with similar traits. We also compared whether the climate envelopes were representative of other environmental groupings, including the Interim Biogeographical Regionalisation of Australia (IBRA) and soil types. Pivotal results. Plant trait values were significantly different among populations (P ≤ 0.001) and soil types (P ≤ 0.003). All traits, except main stem diameter and distance to closest conspecific, were significantly different among bioregions. Seven climate envelopes were identified across sampled populations, and plant trait values within climatically similar populations were highly dissimilar (global R = 0.09). IBRA regions and soil types showed greater similarity with plant traits (global R = 0.27 and 0.25, respectively). Conclusions. This study demonstrates how the collection of data on plant traits and other environmental factors beyond climate can improve models of species distributions. Consequently, studies that rely on climate-only data—or single broad climate envelopes—may be too general or disconnected from the population-level processes that shape the persistence and distribution of species across the landscape.