Miocene Wilkinsonia fruits (Hicksbeachiinae, Proteaceae) from the base of the Yallourn Formation, Latrobe Valley, Victoria

Wilkinsonia bilaminata F. Muell., 1879 is recorded from interseam clays at the base of the Yallourn Formation, Latrobe Valley, Victoria. The genus was widely distributed throughout eastern Australia during the Oligo-Miocene. The palynological record for both Yallourn and the type locality has not suggested that either Athertonia, the most closely related extant taxon, or the subtribe Hicksbeachiinae were present in these localities. There are two inferences from these results; the suggested affinities of some of the pollen taxa may be in error, or the pollen of the Wilkinsonia plant may be under-represented in these sites and has been overlooked

The species of Sphaerolobium (Fabaceae) in Tasmania

Two species of the globe pea Sphaerolobium occur in Tasmania: Sphaerolobium minus Labill. and S. vimineum Sm. Information on their morphology, distribution and conservation status in the state is discussed based primarily upon Tasmanian Herbarium (HO) records. The leaf morphology of both species is described

Elaeocarpus (Elaeocarpaceae) endocarps from the Oligo-Miocene of Eastern Australia

Elaeocarpus peterii.sn nov. is described from the Oligo-Miocene Glencoe locality in central Queensland. This species has prominent stellate ridges and fine punctate ornamentation. These features support a close relationship to extant E. steffaris L.S. Smith fronl northeastern Queenlsland.Elaeocarpus clarkei(F. Muell). Selling is redescribed. The punctate ornamentation and large oval endocarps of E. clarkei (F. Meull) are closely comparable to extant E. bancroftii F. Muell. & F.M. Bail. and E. linsmithii G.P. Guymer from north eastern Queensland. Elaeocarpus clarkei is a common element in many oligo-Miocene deep leads in southeastern Australia. The age of some of the deep leads (buried placer deposits) in Victoria, e.g. Haddon and Foster, is discussed; the limited data available suggests a minimum mid-Miocene age for these localities

Oldest Known Eucalyptus Macrofossils Are from South America

The evolutionary history of Eucalyptus and the eucalypts, the larger clade of seven genera including Eucalyptus that today have a natural distribution almost exclusively in Australasia, is poorly documented from the fossil record. Little physical evidence exists bearing on the ancient geographical distributions or morphologies of plants within the clade. Herein, we introduce fossil material of Eucalyptus from the early Eocene (ca. 51.9 Ma) Laguna del Hunco paleoflora of Chubut Province, Argentina; specimens include multiple leaves, infructescences, and dispersed capsules, several flower buds, and a single flower. Morphological similarities that relate the fossils to extant eucalypts include leaf shape, venation, and epidermal oil glands; infructescence structure; valvate capsulate fruits; and operculate flower buds. The presence of a staminophore scar on the fruits links them to Eucalyptus, and the presence of a transverse scar on the flower buds indicates a relationship to Eucalyptus subgenus Symphyomyrtus. Phylogenetic analyses of morphological data alone and combined with aligned sequence data from a prior study including 16 extant eucalypts, one outgroup, and a terminal representing the fossils indicate that the fossils are nested within Eucalyptus. These are the only illustrated Eucalyptus fossils that are definitively Eocene in age, and the only conclusively identified extant or fossil eucalypts naturally occurring outside of Australasia and adjacent Mindanao. Thus, these fossils indicate that the evolution of the eucalypt group is not constrained to a single region. Moreover, they strengthen the taxonomic connections between the Laguna del Hunco paleoflora and extant subtropical and tropical Australasia, one of the three major ecologic-geographic elements of the Laguna del Hunco paleoflora. The age and affinities of the fossils also indicate that Eucalyptus subgenus Symphyomyrtus is older than previously supposed. Paleoecological data indicate that the Patagonian Eucalyptus dominated volcanically disturbed areas adjacent to standing rainforest surrounding an Eocene caldera lake

Synchrotron computer tomographic (CT) scans complement traditional techniques in understanding the internal anatomy of permineralised Fontainocarpa (Crotonoideae, Euphorbiaceae) fruits from the Oligocene of eastern Australia

The internal morphology and anatomy of silicified fruits of Fontainocarpa were studied using traditional thin sectioning techniques, SEM and synchrotron computed tomographic (CT) imaging and animations, to enable comparative analyses with extant, indehiscent-fruited genera in the Euphorbiaceae including Fontainea, Aleurites and Hylandia from Australia, and other non-Australian crotonoid genera. Thin sections and sectioning show that the fruits of Fontainocarpa are indehiscent, multicarpellate and usually 3- to 5-loculate, with axial placentation, a single ovule per carpel and the ovules are anatropous and have antitropous curvature. A ventral vascular trace that supplies each ovule is embedded in the bitegmic seed coat. The internal anatomy is therefore consistent with the Euphorbiaceae. Additional characters, including indehiscent fruits, distinctive vascular channels (foramina) that penetrate through the fruit wall into the locule, and thin membranous seed coats are restricted to very few genera in the Euphorbiaceae, but occur together in extant Fontainea. The seed coat in extant Fontainea and fossil Fontainocarpa seeds is membranous, and appears to lack the palisadal exotegmen of most genera in the Euphorbiaceae. Fontainocarpa fruits were compared with those of extant Fontainea and the fossil has a combination of features unlike those of extant taxa. It shares with Fontainea picrosperma in having endocarps with convex intersutural surfaces lacking ornamentation and a similar number of locules and with Fontainea venosa in having conspicuous foramina. This study therefore supports a close relationship between Fontainea and Fontainocarpa and is further evidence of the Crotonoideae in the fossil record in Australia, and is one of the few records of this subfamily worldwide. This study is one of the few, to date, using synchrotron CT imaging to reveal the internal morphology of silicified fruits and to utilize animations to examine the structure of these fruits. © 2017 Elsevier B.V

Chemistry of the Australian Gymnosperms. Part IX: The Leaf Oils of the Australian Members of the Genus 'Callitris' (Cupressaceae)

The leaf oils of the 18 species and four subspecies of the genus 'Callitris' endemic to Australia have been investigated by a combination of GC and GC/MS. All taxa produced oils in poor to moderate yields. 'Callitris baileyi' produced a leaf oil in which α-pinene and limonene together, contributed the majority of the oil, while in 'Callitris canescens' methyl citronellate also made significant contributions to the oil. In 'C. columellaris', limonene was the principal component, contributing up to 78% of the oil. 'Callitris drummondii' gave a leaf oil which showed two chemical varieties. The samples from Western Australia contained large amounts of α-pinene (67-69%), while the sample from South Australia contained limonene (10.9%), bornyl acetate (24.2%) and geranyl acetate (14.9%) as significant components. In 'C. endlicheri' the main components were limonene, α-pinene and bornyl acetate. Limonene and α-pinene were the principal components of the leaf oil of 'C. glaurophylla'. 'Callitris gracilis' ssp. 'gracilis' gave an oil in which the principal components were α-pinene, myrcene and limonene, while in ssp. 'murrayensis' α-pinene was the principal component. α-Pinene and limonene were the principal components of 'C. intratropica' and 'C. macleayana'. 'Callitris muelleri' was found in two chemical forms, one monoterpenoid and one sesquitepenoid, with either α-pinene or spathulenol being the principal component. In 'C. oblonga', which consists of three subspecies, α-pinene was the main component. In 'C. preissii' the major components were α-pinene, myrcene, limonene and bornyl acetate. 'Callitris rhomboidea' was distinguished from the vast majority of other 'Callitris' species by containing significant amounts of neryl acetate, geranyl acetate and citronellyl acetate. 'Callitris roei' contained significant amounts of sesquiterpenes in its leaf oil, with (E)-nerolidol being the principal component. In 'C. tuberculata' α-pinene and limonene were the major components. α-Pinene, limonene and camphor were the major components in the leaf oil of 'C. verrucosa', while in 'Callitris' sp. (Emerald Falls P.I. Forster +PIF26357) α-pinene and limonene were the principal components with significant amounts of α-fenchyl acetate. The leaf oil of the putative introgressed populations of 'C. columellaris' - 'C. verrucosa' had α-pinene (25-46%), myrcene (9-19%), limonene (14-24%), α-fenchyl acetate (8-13%) and bornyl acetate (4-13%) as the most significant components. The oil does provide similarities to the oils of both putative parent species in that it contains camphor (1-3%), which is characteristic of 'C. verrucosa' and bornyl acetate (2-13%) characteristic of 'C. glaucophylla'

Synchrotron computer tomographic (CT) scans complement traditional techniques in understanding the internal anatomy of permineralised Fontainocarpa (Crotonoideae, Euphorbiaceae) fruits from the Oligocene of eastern Australia

The internal morphology and anatomy of silicified fruits of Fontainocarpa were studied using traditional thin sectioning techniques, SEM and synchrotron computed tomographic (CT) imaging and animations, to enable comparative analyses with extant, indehiscent-fruited genera in the Euphorbiaceae including Fontainea, Aleurites and Hylandia from Australia, and other non-Australian crotonoid genera. Thin sections and sectioning show that the fruits of Fontainocarpa are indehiscent, multicarpellate and usually 3- to 5-loculate, with axial placentation, a single ovule per carpel and the ovules are anatropous and have antitropous curvature. A ventral vascular trace that supplies each ovule is embedded in the bitegmic seed coat. The internal anatomy is therefore consistent with the Euphorbiaceae. Additional characters, including indehiscent fruits, distinctive vascular channels (foramina) that penetrate through the fruit wall into the locule, and thin membranous seed coats are restricted to very few genera in the Euphorbiaceae, but occur together in extant Fontainea. The seed coat in extant Fontainea and fossil Fontainocarpa seeds is membranous, and appears to lack the palisadal exotegmen of most genera in the Euphorbiaceae. Fontainocarpa fruits were compared with those of extant Fontainea and the fossil has a combination of features unlike those of extant taxa. It shares with Fontainea picrosperma in having endocarps with convex intersutural surfaces lacking ornamentation and a similar number of locules and with Fontainea venosa in having conspicuous foramina. This study therefore supports a close relationship between Fontainea and Fontainocarpa and is further evidence of the Crotonoideae in the fossil record in Australia, and is one of the few records of this subfamily worldwide. This study is one of the few, to date, using synchrotron CT imaging to reveal the internal morphology of silicified fruits and to utilize animations to examine the structure of these fruits. © 2017 Elsevier B.V