E - International Union for the Protection of New Varieties of Plants

TGP/14/1: Section 2: Botanical Terms
Subsection 2: Shapes and Structures: III. DEFINITIONS FOR SHAPE AND STRUCTURE TERMS
page 59
III.
DEFINITIONS FOR SHAPE AND STRUCTURE TERMS
Term
Abaxial
Acicular
Aciculate
Actinomorphic
Aculeate
Acuminate
Acute
Adaxial
Adherent
Adnate
Adpressed
Anthela
Apex
Apical
Apiculate
Apopetalous
Arachnoid
Arched, Arching
Aristate
Definition / comment
The lower, outer or dorsal side; the side facing away from the axis. Compare
‘adaxial’.
Needle-shaped; rigid, long and narrow and tapering to a fine point. Round or
grooved in transverse section, e.g. conifers. Applies primarily to threedimensional
shape but may also be used for the outline.
With fine, straight stripes, like needle scratches, lying in different directions, and
of a different color or texture. Compare ‘striate’ (parallel lines).
Radially symmetric, so that median division in any direction will produce two
equal halves, e.g. inflorescence of Asteraceae. Compare ‘zygomorphic’.
Type of appendage covered by the general term “spine” in the Test Guidelines.
Bearing prickles; with stiff, sharp projections from the superficial layers of the
plant part.
Compare ‘spinose’ (from the superficial and deeper layers).
Tapering gradually, with concave margins, to a sharp or blunt tip. Applies to the
apex. Compare ‘apiculate’, tapering more abruptly and ‘caudate’, tapering more
gradually, both applying to the tip only.
With straight or slightly convex margins, at an angle of less than 90 º. Applies to
the base, apex, etc. Compare ‘obtuse’ where the angle is >90 º. In cases where it
is useful to distinguish between ‘narrow acute’ and ‘broad acute’, one should
remember that they should both still be