pteridosperm

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Related to Pteridosperms: Cordaites, Pteridospermatophyta

pteridosperm

(ˈtɛrɪdəˌspɜːm)
n
1. (Plants) any extinct seed-producing fernlike plant of the group Pteridospermae. Also called: seed fern
2. (Palaeontology) any extinct seed-producing fernlike plant of the group Pteridospermae. Also called: seed fern
[C19: from Greek pteris a fern + -sperm]

seed′ fern`


n.
any of various fossil plants of the order Lyginopteridales (or Cycadofilicales) that had fernlike leaves and reproduced by means of seeds. Also called pteridosperm.
[1925–30]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.pteridosperm - an extinct seed-producing fernlike plant of the order Cycadofilicales (or group Pteridospermae)pteridosperm - an extinct seed-producing fernlike plant of the order Cycadofilicales (or group Pteridospermae)
gymnosperm - plants of the class Gymnospermae having seeds not enclosed in an ovary
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References in periodicals archive ?
Evidence for pollination-drop mechanism in Paleozoic pteridosperms.
8h) with minor contributions from lycopsids (Lepidodendron and Lepidophloios), sphenopsids (Calamites), and possible tree ferns and pteridosperms (Ielpi et al.
Evidence for a pollination-drop mechanism in Paleozoic pteridosperms.
Pteridosperms, or seed-ferns, were one of the most diverse and widespread elements of Late Paleozoic tropical rainforests (DiMichele et al.
Late Gzhelian pteridosperms with callipterid foliage of the Donets Basin, Ukraine.
Drifted lycopsid plants predominate in the basal limestones, whereas overlying siltstones and sandstones contain a mixed suite of drifted gymnosperms (cordaitaleans), sphenopsids (primarily calamiteans), pteridosperms and putative progymnosperms (Falcon-Lang 2003a).
From this Psilophyton-like type were derived two lines of evolution--the lycopods, on the one hand, which retained their phylloids and dichotomous cauloids, and, on the other, all other vascular cryptogams, the pteridosperms, all gymnosperms and angiosperms.
Medullosan pteridosperms and cordaitaleans were assisted through dry periods by a substantial root system, which allowed them to tap deep groundwater sources (Falcon-Lang and Bashforth 2004).
DiMichele and Phillips (1977) described the monocyclic Psaronius simplicicaulis from an Early Pennsylvanian bedrock valley-fill succession in Illinois (Leary 1981), where it was associated with an upland/dryland assemblage of cordaitaleans, pteridosperms, and noeggerathialians (Leary 1975, 1993).