bisporangiate

bisporangiate

[¦bī·spə′ran·jē‚āt]
(botany)
Having two different types of sporangia.
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References in periodicals archive ?
a functional bisporangiate compound cone) rather than a teratology.
But the extensive evidence for parasitic insects in extinct seed plants making a switch to become pollinators has also to account for a switch from unisporangiate to bisporangiate strobili.
Bisporangiate strobili: the presumed ancestral Angiosperm character.
Styphelioideae are supported as monophyletic by the presence of bisporangiate anthers (char.
55), bisporangiate, usually monothecal anthers (char.
Stamens (2-)5-10(-16), free from the corolla or adnate, sometimes connate, included or exserted, the filaments straight to variously curved, unicellular-pubescent or glabrous; anthers tetrasporangiate or bisporangiate, inverting (late, or more commonly early) in development, with 2 or 4 apparently terminal or dorsal appendages (awns, spurs) or these sometimes on the filaments, opening by pores or short to long slits, sometimes through narrowed tubules, an endothecium usually lacking.
However, in the Secamonoideae with functionally bisporangiate anthers, it is the two inner (ventral) ones that are reduced (Civeyrel, 1995, 1996), whereas in the Asclepiadoideae it is the two outer (dorsal) ones that have become obsolete.
Androecium: stamens [1 (Usteria)-]4-5(-16), isomerous, alternipetalous, adnate to corolla: anthers bisporangiate or tetrasporangiate, dithecal and introrse; dehiscing via longitudinal slits; usually isostylous, occasionally heterostylous (Gelsemieae); usually free, rarely connivent (Gardneria).