orthotropous


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orthotropous

[ȯr′thä·trə·pəs]
(botany)
Having a straight ovule with the micropyle at the end opposite the stalk.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Characters that support positions in this part of the tree are the continuous tectum and sessile stigma, as in Amborella and Nymphaeales (symplesiomorphies), and the orthotropous ovule, as in Amborella (either a symplesiomorphy or a synapomorphy).
The female flowers consist of a single carpel, which lacks the hooked hairs of Appomattoxia but also contains a single pendent, orthotropous seed, which is more elongate than the seed of Appomattoxia but similar in having thick-walled cells around the micropyle.
When Pseudoasterophyllites was added to the J/M tree, where Chloranthaceae and Ceratophyllum are well separated, its most parsimonious position was sister to Chloranthaceae, supported by opposite or whorled leaves, stephanocytic stomata, sessile, unisexual flowers, one stamen, embedded pollen sacs, supratectal spinules, one carpel, and orthotropous ovule, but a position with Ceratophyllum was only one step less parsimonious.
(2015) associated it with carpels with a single ovule resembling that of Pseudoasterophyllites and Appomattoxia in being pendent and orthotropous and having an area of thicker-walled cells around the micropyle.