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Trigonobalanoidea (disused)
Taxonomy
Trigonobalanoidea was named by Crepet and Nixon (1989). Its type is Trigonobalanoidea americana.
It was assigned to Fagoideae by Crepet and Nixon (1989).
It was assigned to Fagoideae by Crepet and Nixon (1989).
Synonymy list
| Year | Name and author |
|---|---|
| 1989 | Trigonobalanoidea Crepet and Nixon |
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If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
Subfm. †Trigonobalanoidea Crepet and Nixon 1989
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Diagnosis
| Reference | Diagnosis | |
|---|---|---|
| W. L. Crepet and K. C. Nixon 1989 | Immature pistillate infrutescences and dispersed fruits. Infructescences elongate, unbranched, with a straight to slightly curved axis bearing alternately arranged cupules. Cupules scaly, obscurely lobed, partially enclosing up to three trigonous fruits. Styles 3 per fruit, divergent, ca. 2 mm long. Stigmas terminal, capitate or discoid. Mature dispersed fruits: Fruits with valvate cupules enclosing about 2/3 of the fruit. Cupule scales tongue-shaped, arranged in (sometimes obscure) transverse rows. Fruits 1-3 in each cupule, trigonous, winged, with an indument of elongate simple trichomes particularly along wings and apices. Perianth often persistent at fruit apex, with 3 styles that expand distally to the capitate stigmatic region. Triangular attachment scar visible basally on some solitary dispersed fruits. |