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Focussed searches were made across New Zealand between 2013 and 2016, for endemic aphids from the Schizaphis (Rhopalosiphina) genus, which is currently represented by two putative, undescribed species from the endemic host plants Aciphylla and Dracophyllum. Cytochrome c oxidase I (COI) gene sequences (48 in total) from the Schizaphis were analysed together with those from a broader collection of New Zealand endemic aphids that has been assembled since the year 2000. The bulk of the Schizaphis belonged to two clusters corresponding to the host plant genera. Two aphids from central North Island Dracophyllum represented a much diverged lineage without clear affiliations to other New Zealand Schizaphis. Inter-population variation in the New Zealand Schizaphis was high compared with that seen in international studies of Aphidinae and among populations of other endemic New Zealand Aphidina. Within Schizaphis from Dracophyllum, geography played an apparent role in genetic structuring, with populations from Taranaki (North Island) and especially Mt Lyford (South Island) being divergent from those on the South Island main divide. Two distinct lineages of Schizaphis, which co-occurred at some sites, were found on Aciphylla. Our sequence comparisons, including GMYC analyses, indicated up to five New Zealand Schizaphis lineages, and two newly discovered endemic Aphis species from the host plants Clematis and Hebe. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the diversity and prevalence of Fusarium species in a survey of cereal and grassland systems from the South Island of New Zealand by applying morphological and molecular techniques. Isolates were collected from soil, roots, and stems from 21 cereal and grassland sites. Ten Fusarium species were identified using morphological characters, including F. acuminatum, F. avenaceum, F. crookwellense, F. culmorum, F. equiseti, F. oxysporum, F. poae, F. pseudograminearum, F. sambucinum, and F. tricinctum. In general, their distribution was found to be unrelated to biogeographical location, although agricultural practice increased the overall diversity of Fusarium. Phylogenetic analyses were successfully used to identify morphologically similar isolates belonging to the F. avenaceum/F. acuminatum/F. tricinctum species complex and to resolve previously undetermined relationships amongst these species. Fifty-eight isolates classified as either F. avenaceum, F. acuminatum, or other closely related species as well as several well-characterised isolates from international culture collections were examined using DNA sequence data for β-tubulin (βTUB), translation elongation factor 1α (EF1α), and mitochondrial small subunit ribosomal RNA (mtSSU). Analyses of DNA sequence data from both βTUB and EF1α discriminated among isolates of F. avenaceum, F. acuminatum, and F. tricinctum and determined that these three distinct sequence groups formed a single clade. By contrast, mtSSU was unable to differentiate F. avenaceum from F. acuminatum and other closely related species believed to be F. tricinctum. Comparison of the EF1α sequences with the international FUSARIUM-ID database supported the identification of isolates in this study. As in other studies, F. avenaceum was found to be widespread in agricultural and native ecosystems. However, F. acuminatum in New Zealand was found only on non-wheat hosts. The reason for the absence of this wheat pathogen in cereal-based ecosystems in New Zealand remains unknown., (Copyright © 2010 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

The African flat lizard genus Platysaurus is widely distributed on rock outcrops in southern Africa and is found both east and west of the Kalahari Desert and between major river drainage systems. We assembled a molecular phylogeny for the genus in order to test several biogeographic hypotheses. Sequence data were obtained from 29 specimens representing 14 taxa of Platysaurus that span the geographic range of the genus. We targeted a fragment of the mitochondrial genome comprising the 3' half of the ND4 gene and most of the flanking tRNA-HSL cluster. The edited alignment comprised 864 characters, of which 479 (55%) were variable and 461 (96%) parsimony informative. Overall, the phylogeny was well resolved and supported by high bootstrap values. Four major clades were identified comprising two to seven species: P. mitchelli and P. maculatus maculatus from the north-eastern range of the genus; P. broadleyi and P. capensis from the western range; P. imperator, P. torquatus, and P. intermedius rhodesianus; P. i. intermedius, P. monotropis, P. minor, P. i. nigrescens, P. lebomboensis, P. i. wilhelmi, and P. o. orientalis. Platysaurus has been suggested to represent a recent adaptive radiation where rapid speciation was fuelled by population fragmentation brought on by vicariant events and possibly divergent sexual selection. The traditional explanation for the radiation of the genus is that the eastern migration of the Kalahari sands fragmented populations in the Plio-Pleistocene, resulting in conditions favorable for speciation. Our genetic data strongly suggests that many of the speciation events in Platysaurus already had occurred prior to the Plio-Pleistocene. Moreover, vicariant events associated with the formation of the major river systems played an additional role in the evolution and distribution of Platysaurus species. Our topology displays long internodes and long terminal branches, suggesting that the radiation is much older than previously believed.