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The record of fossil monocotyledonous pollen in New Zealand is summarized and discussed in terms of age and palaeoecological implications. The fossil monocot pollen record covers reports of taxa variously ranging from the Palaeogene to the present, with diverse groups represented, including Alstroemeriaceae: Luzuriagoideae ( Luzuriaga), Amaryllidaceae (aff. Hymenocallis?), Arecaceae (including Nypa and aff. Metroxylon), Asparagaceae: Lomandroideae ( Arthropodium, Cordyline), Asteliaceae ( Astelia and Collospermum), Cyperaceae, Anarthriaceae (including Hopkinsiaceae and Lyginiaceae) or Flagellariaceae?, Orchidaceae, Pandanaceae, Poaceae, Restionaceae (aff. Empodisma), Ripogonaceae ( Ripogonum), Typhaceae ( Typha and Sparganium) and Asphodelaceae (= Xanthorrhoeaceae): Hemerocallidoideae ( Dianella and Phormium). There are also monosulcate and reticulate lilioid and echinate and gemmate arecoid palynomorphs known from the Late Cretaceous. The possible biogeographical and palaeoecological implications of these records, especially for tropical or subtropical taxa occurring at mid to high southern latitudes, are also discussed. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178, 421-440. [ABSTRACT FROM AUTHOR]

The macrofossil record of monocotyledons for New Zealand and Australia is updated on the basis of recent finds. In particular, reports for mummified leaf fossils with good cuticular preservation reveal significant fossil age or range extensions for a number of families in several different orders, including Ripogonaceae in the Eocene of Tasmania and New Zealand (and South America), and calamoid and other Arecaceae from the Eocene of southern New Zealand. There are also earliest macrofossil records for several families or subfamilies, including Alstroemeriaceae: Luzuriagoideae ( Luzuriaga), Arecaceae, Asparagaceae: Lomandroideae ( Cordyline), Asteliaceae ( Astelia), Cymodoceaceae (aff. Ruppia), Cyperaceae, Restionaceae, Orchidaceae: Epidendroideae ( Dendrobium and Earina), Asphodelaceae (previously Xanthorrhoeaceae): Hemerocallidoideae ( Dianella/ Phormium) and Xeronemataceae ( Xeronema) from the Miocene of New Zealand. In addition, an Ensete-like seed associated with Pakawaua ( Musaceae) and a leaf fragment of a second Musaceae-like species of Miocene age are presented. The biogeographical and palaeoecological implications of these records, especially for tropical or subtropical taxa occurring at mid to high southern latitudes, is discussed. In particular, the role and ecology of the relatively high-diversity monocot fossils in the sclerophyllous swamp forest at Newvale Mine in Southland and the lake-edge rainforest at Foulden Maar are explored. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178, 394-420. [ABSTRACT FROM AUTHOR]

Outcrossing rates and seed set were estimated at both the population and individual plant scale within four populations of Xanthorrhoea johnsonii. Sites differed with respect to habitat disturbance (time since fire), plant density, mean plant height, and mean inflorescence length. Allozyme data from progeny arrays of 24 seeds per plant from ten plants at each site were used to determine maternal outcrossing rates, which were found to be consistently high at all sites (> 90%). Small but significant levels of inbreeding were recorded at three of the four sites. There was close agreement between tm and ts measures, which indicated that most inbreeding was a result of within plant selfing rather than biparental inbreeding. Outcrossing rates were estimated within top, middle, and bottom thirds of spikes on six plants at a fifth site. Significant differences from complete outcrossing were recorded in the middle and/or bottom sections of three plants. Total seed set per plant and seed set per flower varied significantly among the four sites. Xanthorrhoea johnsonii appears to be able to maintain relatively high outcrossing rates under different ecological conditions, although levels of both seed set per plant and seed set per flower are much more variable. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110, 335-345. [ABSTRACT FROM AUTHOR]

Background and Aims Microsporogenesis leading to monosulcate pollen grains has already been described for a wide range of monocot species. However, a detailed study of additional callose deposition after the completion of the cleavage walls has been neglected so far. The study of additional callose deposition in monosulcate pollen grain has gained importance since a correlation between additional callose deposition and aperture location has recently been revealed. Methods Microsporogenesis is described for 30 species belonging to eight families of the monocots: Acoraceae, Amaryllidaceae, Alstroemeriaceae, Asparagaceae, Butomaceae, Commelinaceae, Liliaceae and Xanthorrhoeaceae. Key Results Five different microsporogenesis pathways are associated with monosulcate pollen grain. They differ in the type of cytokinesis, tetrad shape, and the presence and shape of additional callose deposition. Four of them present additional callose deposition. Conclusions In all these different microsporogenesis pathways, aperture location seems to be linked to the last point of callose deposition. [ABSTRACT FROM PUBLISHER]

Background and Aims Pollen-collecting bees are among the most important pollinators globally, but are also the most common pollen thieves and can significantly reduce plant reproduction. The pollination efficiency of pollen collectors depends on the frequency of their visits to female(-phase) flowers, contact with stigmas and deposition of pollen of sufficient quantity and quality to fertilize ovules. Here we investigate the relative importance of these components, and the hypothesis that floral and inflorescence characteristics mediate the pollination role of pollen collection by bees. Methods For ten Aloe species that differ extensively in floral and inflorescence traits, we experimentally excluded potential bird pollinators to quantify the contributions of insect visitors to pollen removal, pollen deposition and seed production. We measured corolla width and depth to determine nectar accessibility, and the phenology of anther dehiscence and stigma receptivity to quantify herkogamy and dichogamy. Further, we compiled all published bird-exclusion studies of aloes, and compared insect pollination success with floral morphology. Key Results Species varied from exclusively insect pollinated, to exclusively bird pollinated but subject to extensive pollen theft by insects. Nectar inaccessibility and strong dichogamy inhibited pollination by pollen-collecting bees by discouraging visits to female-phase (i.e. pollenless) flowers. For species with large inflorescences of pollen-rich flowers, pollen collectors successfully deposited pollen, but of such low quality (probably self-pollen) that they made almost no contribution to seed set. Indeed, considering all published bird-exclusion studies (17 species in total), insect pollination efficiency varied significantly with floral shape. Conclusions Species-specific floral and inflorescence characteristics, especially nectar accessibility and dichogamy, control the efficiency of pollen-collecting bees as pollinators of aloes. [ABSTRACT FROM AUTHOR]

We provide here a subfamilial scheme for the expanded asparagalean families Amaryllidaceae, Asparagaceae and Xanthorrhoeaceae. Our recommendation is that the first family has three subfamilies (Agapanthoideae, Allioideae and Amaryllidoideae), the second has seven (Agavoideae, Aphyllanthoideae, Asparagoideae, Brodiaeoideae, Lomandroideae, Nolinoideae and Scilloideae) and the last has three (Asphodeloideae, Hemerocallidoideae and Xanthorrhoeoideae). Tribal names are provided for the large subfamilies Allioideae, Amaryllidoideae and Scilloideae. The use of these subfamily names permits easier descriptions of characters by specialists for these well-supported subclades, but the use of the broader family limits greatly simplifies the taxonomy of Asparagales and thus makes the teaching of these families much easier. A new subfamilial name, Xanthorrhoeoideae, and a new tribal name, Oziroëeae, are proposed. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161, 132–136. [ABSTRACT FROM AUTHOR]

Leaf surface morphology was analysed in 32 species representing the maculate species complex (the poorly resolved section Pictae) in the genus Aloe (Xanthorrhoeaceae). Few comparative morphological data are available for the complex. Leaf surface and stomatal characters observed by scanning electron microscopy show taxonomically significant interspecific variation. Most species are characterized by irregularly outlined, four- to six-sided epidermal cells, the periclinal walls of which are flat and embellished with micropapillae and the anticlinal walls of which are indicated by channels on the leaf surface. The outer stomatal pore is typically sunken or plane and surrounded by four lobes on the leaf surface that may overarch the epistomatal chamber. The guard cells have distinct outer and inner stomatal ledges. Two geographical groups, comprising southern and east African species, are distinguishable by their leaf surface morphology. These characters are diagnostic in A. ellenbeckii, A. prinslooi and A. suffulta and support changes in the delimitation of A. greatheadii, A. macrocarpa and A. swynnertonii. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160, 418–428. [ABSTRACT FROM AUTHOR]