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1.
Am J Bot ; 106(2): 292-302, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30791095

RESUMO

PREMISE OF THE STUDY: An Akania-like inflorescence, including flowers with in situ pollen was recovered from the remarkable Konservat-Lagerstätte lacustrine diatomite deposit at Foulden Maar, Otago indicating the presence of Akaniaceae in southern New Zealand during the early Miocene. The flowers, although slightly smaller than the sole modern Australian species, A. bidwillii, contain pollen grains that are very like that taxon. The pollen also resembles that of the monospecific sister genus Bretschneidera from Southeast Asia and India, although that taxon has flowers with very different morphology from this genus. METHODS: The floral morphology of the fossil and in situ pollen grains were compared with flowers and pollen grains from extant species of Akaniaceae and related taxa. KEY RESULTS: The fossil inflorescence and associated pollen are referred to a new, extinct species of Akania: Akania gibsonorum. The floral structures and pollen resemble those of the modern Australian Akania species. CONCLUSIONS: The discovery of fossil flowers of Akania in an early Miocene lake deposit in New Zealand, coupled with earlier recognition of Akaniaceae leaves from the Paleocene epoch and wood from the Miocene epoch in South America suggests that the genus was once widespread in former Gondwana landmasses. The extinction of Akaniaceae in New Zealand and South America, and its present relictual distribution in eastern Australia, is most likely related to post-Miocene climatic cooling.


Assuntos
Fósseis/ultraestrutura , Inflorescência , Magnoliopsida , Nova Zelândia , Pólen/ultraestrutura
2.
PeerJ ; 5: e2985, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28224051

RESUMO

Plants and insects are key components of terrestrial ecosystems and insect herbivory is the most important type of interaction in these ecosystems. This study presents the first analysis of associations between plants and insects for the early Miocene Hindon Maar fossil lagerstätte, Otago, New Zealand. A total of 584 fossil angiosperm leaves representing 24 morphotypes were examined to determine the presence or absence of insect damage types. Of these leaves, 73% show signs of insect damage; they comprise 821 occurrences of damage from 87 damage types representing all eight functional feeding groups. In comparison to other fossil localities, the Hindon leaves display a high abundance of insect damage and a high diversity of damage types. Leaves of Nothofagus(southern beech), the dominant angiosperm in the fossil assemblage, exhibit a similar leaf damage pattern to leaves from the nearby mid to late Miocene Dunedin Volcano Group sites but display a more diverse spectrum and much higher percentage of herbivory damage than a comparable dataset of leaves from Palaeocene and Eocene sites in the Antarctic Peninsula.

3.
Am J Bot ; 103(5): 938-56, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27208361

RESUMO

PREMISE OF THE STUDY: The history of the basal angiosperm family Monimiaceae is based largely on fossil wood and leaf and floral fossils of uncertain affinity. Fossilized leaves with a well-preserved cuticle and Hedycarya-like flowers, including one with in situ pollen tetrads and fruits from an early Miocene lacustrine diatomite deposit in southern New Zealand implies a long record for Hedycarya in New Zealand. The flowers contain pollen grains that are very similar to those of the modern New Zealand species Hedycarya arborea and the Australian H. angustifolia but are considerably smaller. METHODS: We undertook comparative studies of the leaf, flower and fruit morphology of the newly discovered macrofossils and compared the in situ pollen grains from the flower with dispersed pollen grains from extant species. KEY RESULTS: The leaves are referred to a new, extinct species, Hedycarya pluvisilva Bannister, Conran, Mildenh. & D.E.Lee, (Monimiaceae), and associated with fossilized Hedycarya-like flowers that include in situ pollen and an infructescence of three drupes from the same site. Phylogenetic analysis placed the fossil into Hedycarya, sister to H. angustifolia in a clade with H. arborea and Levieria acuminata. A new name, Planarpollenites fragilis Mildenh., is proposed for dispersed fossil pollen tetrads at the site and those associated with the flower. CONCLUSIONS: The fossils are similar to those of modern Australian and New Zealand Hedycarya species, suggesting that the genus and related taxa have been significant components of the rainforests of Australia and the former Zealandian subcontinent for most of the Cenozoic.


Assuntos
Fósseis , Magnoliopsida/anatomia & histologia , Pólen/anatomia & histologia , Flores/anatomia & histologia , Frutas/anatomia & histologia , Geografia , Nova Zelândia , Filogenia , Folhas de Planta/anatomia & histologia , Manejo de Espécimes , Terminologia como Assunto
4.
PLoS One ; 10(6): e0128871, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26083758

RESUMO

The New Zealand endemic bat family Mystacinidae comprises just two Recent species referred to a single genus, Mystacina. The family was once more diverse and widespread, with an additional six extinct taxa recorded from Australia and New Zealand. Here, a new mystacinid is described from the early Miocene (19-16 Ma) St Bathans Fauna of Central Otago, South Island, New Zealand. It is the first pre-Pleistocene record of the modern genus and it extends the evolutionary history of Mystacina back at least 16 million years. Extant Mystacina species occupy old-growth rainforest and are semi-terrestrial with an exceptionally broad omnivorous diet. The majority of the plants inhabited, pollinated, dispersed or eaten by modern Mystacina were well-established in southern New Zealand in the early Miocene, based on the fossil record from sites at or near where the bat fossils are found. Similarly, many of the arthropod prey of living Mystacina are recorded as fossils in the same area. Although none of the Miocene plant and arthropod species is extant, most are closely related to modern taxa, demonstrating potentially long-standing ecological associations with Mystacina.


Assuntos
Evolução Biológica , Quirópteros/fisiologia , Dieta , Fósseis , Filogenia , Animais , Quirópteros/anatomia & histologia , Quirópteros/classificação , Ecossistema , Cadeia Alimentar , Nova Zelândia , Plantas , Floresta Úmida
5.
J Phycol ; 51(5): 1017-21, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26986895

RESUMO

A fossil of the aerophytic green algal genus Phycopeltis (Trentepohliaes, Ulvophyceae) dated to 35 Ma, is reported from the Pikopiko Fossil Forest, Southland, New Zealand. Previous reports of fossilized Phycopeltis have been subsequently synonymized with fungi by other authors; however, our specimen is not vulnerable to their criticisms. Inflated cells present in two approximately concentric rings are interpreted as gametangia, with irregular structures resembling the gametangial pores of modern material; sporophytic material is absent. The fossil resembles the modern disc-forming species P. novae-zelandiae, P. expansa, and P. arundinacea. The limited material available prevents the assignation of a specific epithet, but the habit and dimensions of the fossil clearly fall within those of modern representatives of the genus. Its single cell thickness throughout, absence of distinct melanization, and larger size demonstrate that it is not a fungal shield. The specimen constitutes arguably the most convincing fossil belonging to Trentepohliales, and the first unambiguously for the genus Phycopeltis. It is consistent in age with other known fossils of the order that, when combined with molecular evidence, suggests a terrestrial radiation far more recent than that of land plants.

6.
Biol Lett ; 10(10): 20140647, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25319820

RESUMO

The temporal stability of plant reproductive features on islands has rarely been tested. Using flowers, fruits/cones and seeds from a well-dated (23 Ma) Miocene Lagerstätte in New Zealand, we show that across 23 families and 30 genera of forest angiosperms and conifers, reproductive features have remained constant for more than 20 Myr. Insect-, wind- and bird-pollinated flowers and wind- and bird-dispersed diaspores all indicate remarkable reproductive niche conservatism, despite widespread environmental and biotic change. In the past 10 Myr, declining temperatures and the absence of low-latitude refugia caused regional extinction of thermophiles, while orogenic processes steepened temperature, precipitation and nutrient gradients, limiting forest niches. Despite these changes, the palaeontological record provides empirical support for evidence from phylogeographical studies of strong niche conservatism within lineages and biomes.


Assuntos
Evolução Biológica , Magnoliopsida , Polinização/fisiologia , Traqueófitas , Clima , Florestas , Fósseis , Nova Zelândia , Filogenia , Filogeografia , Reprodução , Fatores de Tempo
7.
Am J Bot ; 101(1): 141-55, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24425789

RESUMO

PREMISE OF THE STUDY: The Foulden Maar lake sediments in Otago, South Island, New Zealand, date to the earliest Miocene and provide an important picture of the diversity of the Australasian biota, paleoecology, and climate at a time when New Zealand had a smaller land area than today. The diverse rainforest contains many taxa now restricted to Australia, New Caledonia, or South America. The presence of Luzuriaga-like fossils in these deposits is important for understanding Alstroemeriaceae evolution and the biogeography of genera shared between New Zealand and South America. METHODS: Leaves and a flower with in situ pollen that resemble extant Luzuriaga are described and placed phylogenetically. Geographic range information and a molecular clock model for the Alstroemeriaceae were used to investigate possible biogeographic scenarios and the influence of the new fossil on inferred divergence times. KEY RESULTS: Luzuriaga peterbannisteri Conran, Bannister, Mildenh., & D.E.Lee sp. nov. represents the first macrofossil record for Alstroemeriaceae. An associated Luzuriaga-like flower with in situ fossil pollen of Liliacidites contortus Mildenh. & Bannister sp. nov. is also described. The biogeographic analysis suggests that there have been several dispersal events across the Southern Ocean for the genus, with the fossil representing a now-extinct New Zealand lineage. CONCLUSIONS: Luzuriaga was present in Early Miocene New Zealand, indicating a long paleogeographic history for the genus, and L. peterbannisteri strengthens biogeographic connections between South America and Australasia during the Oligocene and earliest Miocene.


Assuntos
Cotilédone/anatomia & histologia , Fósseis , Magnoliopsida/anatomia & histologia , Folhas de Planta/anatomia & histologia , Pólen/anatomia & histologia , Relógios Biológicos , Geografia , Nova Zelândia , Filogenia , Fatores de Tempo
8.
Am J Bot ; 100(10): 2052-65, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24107580

RESUMO

PREMISE OF THE STUDY: Fuchsia (Onagraceae) anthers, pollen, and an ornithophilous Fuchsia-like flower from an earliest Miocene lacustrine diatomite deposit at Foulden Maar, southern New Zealand confirm a long record for Fuchsia in New Zealand and probably an equally long history for its distinctive honeyeater pollination syndrome. The anthers contain in situ pollen of the fossil palynomorph previously assigned to Diporites aspis Pocknall et Mildenh. (Onagraceae: Fuchsia L.). • METHODS: We undertook comparative studies of the flower and anther morphology of the newly discovered macrofossils and compared the in situ pollen grains from the anthers with dispersed pollen grains from extant species. • KEY RESULTS: The anther mass is referred to a new, extinct species, Fuchsia antiqua D.E.Lee, Conran, Bannister, U.Kaulfuss & Mildenh. (Onagraceae), and is associated with a fossilized Fuchsia-like flower from the same small mining pit. Because Diporites van der Hammen is typified by a fungal sporomorph, the replacement name for D. aspis is Koninidites aspis (Pocknall & Mildenh.) Mildenh. gen. & comb. nov. Phylogenetic placement of the fossils agrees with a proximal position to either sect. Skinnera or sect. Procumbentes. These are the oldest macrofossils of Fuchsia globally. • CONCLUSIONS: The floral structures are remarkably similar to those of modern New Zealand Fuchsia. They suggest that the distinctive honeyeater bird-pollination syndrome/association seen in modern New Zealand was already established by the late Oligocene-earliest Miocene. The implications for the biogeography and paleoecology of Fuchsia in Australasia are discussed.


Assuntos
Fósseis , Onagraceae/anatomia & histologia , Pólen/anatomia & histologia , Nova Zelândia , Onagraceae/classificação , Onagraceae/ultraestrutura , Filogenia , Pólen/ultraestrutura , Fatores de Tempo
9.
Biol Bull ; 225(3): 125-36, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24445439

RESUMO

The reproductive cycle and growth of the temperate New Zealand rhynchonelliform brachiopod Liothyrella neozelanica was examined over 12 months (December 2010 and December 2011). The research aimed to clarify the spawning cycle, life history, population size, and age structure of L. neozelanica and to enable more direct comparisons with the Antarctic brachiopod Liothyrella uva. Reproduction over the course of a year was quantified by monthly examination of gonad size and gametogenesis. Histological examination indicated a seasonal cycle with prolonged, potentially asynchronous spawning. Increased numbers of large oocytes in July followed by a significant decrease in September suggest that female spawning takes place in early austral spring. A decrease in the proportion of the gonad area occupied by sperm during September suggests a level of spawning synchrony between sexes. Somatic growth was modeled from 60 tagged individuals. A maximum size of ≈ 50-mm shell length is achieved at 17 years of age, and instantaneous growth is highest in juveniles (9.7 mm yr(-1)). Mortality rate was estimated from the age distribution at an instantaneous rate of 0.14 yr(-1). A left-skewed size-frequency distribution implies high mortality in juveniles.


Assuntos
Invertebrados/fisiologia , Distribuição por Idade , Animais , Feminino , Gametogênese/fisiologia , Gônadas/anatomia & histologia , Invertebrados/crescimento & desenvolvimento , Masculino , Nova Zelândia , Densidade Demográfica , Reprodução/fisiologia , Estações do Ano
10.
Am J Bot ; 98(7): 1164-72, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21700805

RESUMO

PREMISE OF THE STUDY: Microcachrys tetragona (Podocarpaceae), endemic to the mountains of Tasmania, represents the only remaining taxon of one of the world's most ancient and widely distributed conifer lineages. Remarkably, however, despite its ∼150 Myr heritage, our understanding of the fossil history of this lineage is based almost entirely on the pollen record. Fossils of Microcachrys are especially important in light of recent molecular phylogenetic and dating evidence. This evidence dates the Microcachrys lineage to the Mesozoic and does not support the traditional placement of Microcachrys as sister to the southeastern Australian genus Pherosphaera. METHODS: We undertook comparative studies of the foliage architecture, cuticle, and paleoecology of newly discovered fossils from the Oligo-Miocene of New Zealand and M. tetragona and discussed the importance of Microcachrys in the context of Podocarpaceae phylogeny. KEY RESULTS: The fossils represent the oldest and first extra-Australian macrofossils of Microcachrys and are described as the new foliage species M. novae-zelandiae. These fossils confirm that the distinctive opposite decussate phyllotaxy of the genus is at least as old as the Oligo-Miocene and contribute to evidence that Microcachrys plants were sometimes important components of oligotrophic swampy habitats. CONCLUSIONS: Leaf fossils of Microcachrys closely comparable with the only extant species confirm that this lineage had a much wider past distribution. The fossil record and recent molecular phylogenetic studies, including that of Microcachrys, also serve to emphasize the important status of Tasmania as a refugium for seed plant lineages.


Assuntos
Fósseis , Folhas de Planta/genética , Traqueófitas/genética , Extinção Biológica , Nova Zelândia , Filogenia , Folhas de Planta/ultraestrutura , Especificidade da Espécie , Tasmânia , Fatores de Tempo , Traqueófitas/classificação , Traqueófitas/ultraestrutura
11.
Am J Bot ; 97(1): 59-70, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21622367

RESUMO

The Australasian Ericaceae epitomize many problems in understanding the biogeography of the southern hemisphere, especially the relative contributions of Gondwanan vicariance and dispersal. Late Cretaceous fossil pollen of the family suggests extreme antiquity of the group in Australasia, but recent phylogenetic evidence suggests much younger histories for most of the groups in that region. This paper documents two new species of latest Oligocene-Early Miocene macrofossils of Ericaceae from New Zealand. Cyathodophyllum novae-zelandiae G.J.Jord. & Bannister gen. and sp. nov. is the oldest record of the tribe Styphelieae, but is of a clade now extinct in New Zealand, possibly related to the Tasmanian genus Cyathodes. Richeaphyllum waimumuensis G.J.Jord. & Bannister sp. nov. is a member of Richeeae, but it is ambiguous as to whether it is a member of the impressive modern New Zealand radiation in Dracophyllum. These fossils emphasize the fact that at least some of the fossil pollen of Ericaceae may have been derived from extinct lineages and therefore should not be used as evidence for the antiquity of any modern New Zealand clade of Ericaceae. New fossils and/or detailed analysis of fossil and extant pollen may help resolve such uncertainty.

12.
Am J Bot ; 97(2): 288-97, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21622389

RESUMO

Fossils can shed new light on plant biogeography and phylogeny. Pinnately lobed leaves from the Oligo-Miocene Newvale lignite mine, South Island, New Zealand are the first extra-Australian leaf fossils of the charismatic genus Banksia (Proteaceae), and they are assigned to a new species, B. novae-zelandiae. Comparison with extant taxa shows that the fossils are best regarded as an extinct stem relative of Banksia because their available features are either plesiomorphic for the genus (notably, the stomata are superficially placed, not sunken in balloon-like pits as in many extant species) or lack evidence of synapomorphies that would enable them to be placed in the crown group. Banksia novae-zelandiae does, however, exhibit two cuticular features that are unique or highly derived for Banksia. These are rugulate subsidiary cell ornamentation and the presence of complex papillae that extensively cover the abaxial leaf surface. The fossils add to the widespread records of the pinnately lobed leaf form in Banksia in Australia beginning in the late Paleocene. This form is now limited to species confined to sclerophyllous heathlands of Mediterranean climate in southwestern Australia. Banksia novae-zelandiae could be part of a lineage that had a long history in New Zealand, perhaps dating to the early Paleogene.

13.
Am J Bot ; 96(2): 466-74, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21628202

RESUMO

Fossil leaves of two Early Miocene orchids (Dendrobium and Earina) are reported from New Zealand. The distinctive, raised tetra- to cyclocytic stomatal subsidiary cells of Earina and characteristic papilla-like absorbing glands and "ringed" guard cells of Dendrobium support the placement of the fossils into these genera. These therefore represent the first Orchidaceae macrofossils with cuticular preservation, the oldest records for subfamily Epidendroideae, as well as the first New Zealand and southern hemisphere fossil records for Orchidaceae. These taxa belong in basal clades to the Vandeae/Cymbideae or Epidendreae (Earina) and the Australasian clade of Dendrobium sensu lato. This phylogenetic placement demonstrates expansion of epiphytic orchids into Zealandia by the mid-Cenozoic and an important role for southern continents in the diversification of Orchidaceae.

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