Journal Articles

Permanent URI for this collectionhttps://mro.massey.ac.nz/handle/10179/7915

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Author: search.filters.author.Tate JASubject: search.filters.subject.New Zealand

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    Evolutionary relationships in Santalales inferred using target capture with Angiosperms353, focusing on Australasian Santalaceae sensu lato
    (CSIRO Publishing, Australia, 2025-08) Anderson BM; Edlund M; James SA; Lepschi BJ; Nickrent DL; Sultan A; Tate JA; Petersen G; Murphy D
    The angiosperm order Santalales comprises more than 2500 species, most of which are hemi- or holoparasitic on other plants, and derive water and nutrients via specialised structures that attach to host roots or stems. The parasitic lifestyle has affected the morphology and genomes of these plants, and classification of the order has been difficult, with outstanding questions about membership of and relationships between families in the order. We chose to focus on improving phylogenetic sampling in the broadly circumscribed Santalaceae sens. lat., with emphasis on Australasian members of Amphorogynaceae and Viscaceae as part of the Genomics for Australian Plants Initiative. We used target capture with the Angiosperms353 bait set to generate a dataset of 318 nuclear loci × 195 samples, including publicly available data from other Santalales families. Phylogenetic inferences using maximum likelihood concatenation and a summary coalescent approach were largely congruent and resolved relationships between most families, agreeing with much of the previous work on the order. Some relationships that have been difficult to resolve remained so, such as branching order among some families in Olacaceae sens. lat. and Santalaceae sens. lat. Denser sampling in Amphorogynaceae and Viscaceae provided new insights into species-level relationships in genera such as Leptomeria and Choretrum, and allowed testing of recent phylogenetic work in Korthalsella. Our new phylogenetic hypothesis is consistent with one origin of root hemiparasitism, two origins of holoparasitism and five origins of aerial parasitism in the order. Although Angiosperms353 was successful, some phylogenetic bias in gene recovery suggests that future studies may benefit from more specific baits and deeper sequencing, especially for Viscaceae.
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    Sequence data support greater taxonomic diversity and a complicated history of hybridisation in New Zealand’s sun orchids - Thelymitra (Orchidaceae)
    (Taylor and Francis Group on behalf of the Royal Society of New Zealand, 2025-06-26) Jones HR; Lehnebach CA; Tate JA
    Thelymitra, commonly known as sun orchids, is a genus of orchids present in New Zealand (NZ), known for their radially symmetrical and brightly coloured flowers. A long history of nomenclatural changes, and a recent and rapid circumscription of Australian (AU) taxa has left our understanding of this genus in NZ lagging. In this study we report two phylogenies of NZ Thelymitra species, based on nuclear (LFY) and plastid (ycf1) sequence data. The phylogenies identify support for several taxa currently only known by tag-names as being distinct from those that are currently described both in NZ and AU, as well as evidence supporting an extensive history of hybrid speciation in this genus in NZ, which had been hypothesised previously for six species. This work has also found evidence for species complexes within NZ Thelymitra that need further molecular and taxonomic work to fully resolve species boundaries. In this study we also demonstrate a novel application of nanopore sequencing of amplicons, that enables the recovery of multiple sequence copies in allopolyploid taxa without the prior need for cloning.
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    Taxonomic revision of the southern hemisphere pygmy forget-me-not group (Myosotis; Boraginaceae) based on morphological, population genetic and climate-edaphic niche modelling data
    (CSIRO Publishing, 2022-05-05) Prebble JM; Symonds VV; Tate JA; Meudt HM; Wilson P
    A taxonomic revision of the southern hemisphere pygmy forget-me-not group (Myosotis L.; Boraginaceae) is presented here. Climate-edaphic niches are modelled and compared for five species in the pygmy group, namely, M. antarctica Hook.f., M. brevis de Lange & Barkla, M. drucei (L.B.Moore) de Lange & Barkla, M. pygmaea Colenso and M. glauca (G.Simpson & J.S.Thomson) de Lange & Barkla, and one unnamed putative taxon, M. "Volcanic Plateau". In this case, niche-modelling data mostly do not aid species delimitation, but morphological and genetic data provide evidence for recognising the following three species within the group: M. brevis and M. glauca (both endemic to New Zealand), and an enlarged M. antarctica (native to New Zealand, Campbell Island and Chile). Myosotis antarctica is here circumscribed to include M. antarctica sens. strict., M. drucei and M. pygmaea. The following two allopatric subspecies of M. antarctica are recognised on the basis of minor morphological differences: subsp. antarctica (formerly M. antarctica from Campbell Island and Chile, M. drucei and M. "Volcanic Plateau") and subsp. traillii Kirk (formerly known by New Zealand botanists as M. pygmaea Colenso, an illegitimate name). For all three species, which are considered Threatened or At Risk, most of their genetic variation is partitioned between rather than within populations, meaning that conserving as many populations as possible should be the priority to minimise risk of extinction.