Project 2359: G. W. Rothwell, R. A. Stockey. 2016. Phylogenetic diversification of Early Cretaceous seed plants: The compound seed cone of Doylea tetrahedrasperma. American Journal of Botany. 103 (5):923-937.
Specimen: Doylea tetrahedrasperma (UA/ALTA:No. P13467)
View: cone segment

Abstract

ABSTRACT
• Premise of the study: Discovery of cupulate ovules of Doylea tetrahedrasperma within a compact, compound seed cone highlights the rich diversity of fructification morphologies, pollination biologies, post-pollination enclosure of seeds, and systematic diversity of in Early Cretaceous gymnosperms.
• Methods: Specimens were studied from anatomical sections prepared by the cellulose acetate peel technique; three-dimensional visualizations were rendered using AVIZO, and phylogenetic analyses of morphological characters were performed using TNT.
• Key results: Doylea tetrahedrasperma has bract/fertile short shoot complexes that are helically arranged within a compact seed cone of compound structure. Individual complexes diverge from the axis as a single unit, and separate distally into a free bract tip and two sporophylls of an axillary fertile shoot. Each sporophyll bears a single, abaxial seed, recurved toward the cone axis, that is enveloped after pollinaton by scale tissue, forming a closed cupule. Ovules are pollinated by bissacate grains that are captured by micropylar pollination horns, and enter the pollen chamber through a narrow micropyle. A phylogenetic analysis of seed plants helps to clarify the systematic affinities of this plant.
• Conclusions: The unique combination of characters shown by Doylea tetrahedrasperma includes the presence of cupulate seeds borne in conifer-like compound seed cones, an ovuliferous scale analogue that is also structurally equivalent to the ovulate stalk of Ginkgo biloba, gymnospermous pollination, and nearly complete enclosure of mature seeds. These features characterize the Doyleales ord. nov., clearly distinguish it from the seed fern order Umkomasiales, and allow for recognition of another recently described Early Cretaceous seed plant as a second species of Doylea. A morphological phylogenetic analysis of seed plants highlights systematic relationships of the Doyleales ord. nov., and emphasizes the explosive phylogenetic diversification of gymnosperms that was underway during the time interval when flowering plants may have originated and/or first began to radiate.  


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Article DOI: 10.3732/ajb.1600030

Project DOI: 10.7934/P2359, http://dx.doi.org/10.7934/P2359
This project containsMatrices
  • 1 Media
  • 1 Matrix
  • 42 Taxa
  • 1 Specimen
  • 111 Characters
Total size of project's media files: 2 MB

Download Project SDD File
Total scored cells: 4540
Total media associated with cells: 0
Total labels associated with cell media: 0
Characters
Total characters: 111
Total characters with associated media: 0
Total characters with media with labels: 0
Total character states: 287
Total character states with associated media: 0
Total character states with media with labels:0
Total unordered/ordered characters:111/0
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MorphoBank Project 2359


    Members

    member name taxa specimens media chars character
    media
    labels
    cell scorings
    (scored, NPA, "-")
    cell
    medialabels
    rules
    Gar Rothwell
    Project Administrator
    Last logged in 05/25/16
    4201111004540
    (3315, 0, 1225)
    000
    MorphoBank Curator
    Full membership
    Last logged in 06/27/16
    0100000
    (0, 0, 0)
    000


    Taxonomic Overview for Matrix 'M23745' (42 Taxa)

    taxon unscored
    cells
    scored
    cells
    no cell
    support
    NPA
    cells
    "-" cellscell images labels on
    cell images
    member
    access
    [1] † Aneurophyton
    Last Modified in 05/31/16
    05252059002
    [2] † Archaeopteris
    Last Modified in 05/31/16
    06363048002
    [3] † Cecropsis
    Last Modified in 05/31/16
    06060051002
    [4] † Elkinsia
    Last Modified in 05/31/16
    07272039002
    [5] † Heterangium
    Last Modified in 05/31/16
    07777034002
    [6] † Lyginopteris
    Last Modified in 05/31/16
    08080031002
    [7] † Callistophyton
    Last Modified in 05/31/16
    07979032002
    [8] † Quaestora
    Last Modified in 05/31/16
    05252059002
    [9] † Medullosa
    Last Modified in 05/31/16
    07877034002
    [10] Ginkgo
    Last Modified in 02/12/16
    09392019002
    [11] † Emporia
    Last Modified in 05/31/16
    07474037002
    [12] Pinus
    Last Modified in 02/12/16
    09796015002
    [13] Podocarpus
    Last Modified in 02/12/16
    09594017002
    [14] Taxus
    Last Modified in 02/12/16
    09292019002
    [15] † Cordaixylon
    Last Modified in 05/31/16
    08181030002
    [16] † Mesoxylon
    Last Modified in 05/31/16
    08080031002
    [17] † Corystosperms
    Last Modified in 05/31/16
    07473038002
    [18] † Peltasperms
    Last Modified in 05/31/16
    14343067002
    [19] † Glossopteris
    Last Modified in 05/31/16
    07473038002
    [20] † Caytonia
    Last Modified in 05/31/16
    05959052002
    [21] Cycadaceae
    Last Modified in 02/12/16
    09999012002
    [22] Zamiaceae
    Last Modified in 05/31/16
    09998013002
    [23] † Bennettitales
    Last Modified in 05/31/16
    08580031002
    [24] † Pentoxylon
    Last Modified in 05/31/16
    17272038002
    [25] Ephedra
    Last Modified in 02/12/16
    09292019002
    [26] Welwitschia
    Last Modified in 02/12/16
    09191020002
    [27] Gnetum
    Last Modified in 02/12/16
    08786025002
    [28] Magnoliaceae
    Last Modified in 05/31/16
    0102100011002
    [29] Eupomatia
    Last Modified in 02/12/16
    09696015002
    [30] Austrobaileya
    Last Modified in 02/12/16
    09999012002
    [31] Chloranthaceae
    Last Modified in 05/31/16
    09290021002
    [32] Laurales
    Last Modified in 05/31/16
    09393018002
    [33] Winteraceae
    Last Modified in 05/31/16
    09898013002
    [34] Eudicots
    Last Modified in 05/31/16
    010195016002
    [35] Aristolochioideae
    Last Modified in 05/31/16
    09696015002
    [36] Piperaceae
    Last Modified in 05/31/16
    09896015002
    [37] Nymphaeales
    Last Modified in 05/31/16
    09693018002
    [38] Monocots
    Last Modified in 05/31/16
    09290021002
    [39] † Charcoalified seeds
    Last Modified in 05/31/16
    01616095002
    [40] Doylea tetrahedrasperma
    Last Modified in 02/12/16
    445252015002
    [41] Doylea mongolica
    Last Modified in 02/12/16
    623434015002
    [42] † Petriellales
    Last Modified in 05/31/16
    445050017002


    Project views

    type number of views Individual items viewed (where applicable)
    Total project views10753
    Project overview1648
    Matrix views1318Matrix landing page (1157 views); Doylea cone matrix (161 views);
    Media views2073Media search (1790 views); M423755 (283 views);
    Taxon list3905
    Bibliography382
    Specimen list840
    Views for media list587




    Project downloads

    type number of downloads Individual items downloaded (where applicable)
    Total downloads from project181
    Matrix downloads40Doylea cone matrix (40 downloads);
    Project downloads141