pinnule


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Related to pinnule: pinnation

pinnule

[′pin‚yül]
(biology)
The secondary branch of a plumelike or pinnate organ.
References in periodicals archive ?
Pinnules entire or lobed, lateral lobes lanceolate; blades turning bronze in winter 5.
There is also evidence that the pinnule laminae do not overlap and the pinnules do not show the pronounced biconvex ("roof shape") morphology described above in cf.
27) in pinna axes and pinnules of a number of scrambling/climbing late Paleozoic pteridosperms (Stidd & Phillips, 1973; Rothwell, 1975; Krings, 1997, 2000; Krings & Kerp, 2000).
the typical or trifoliate pinnule is actually homologous to an imparipterid ultimate pinna that normally is composed of a number of lateral pinnules with one definite terminal pinnule.
Figure 11a shows the tip region of a primary or secondary pinna with 2 cm long pinnules homologous to ultimate pinnae, which then change to pinnatifid pinnules in which subsidiary veins tend to dominate.
It is beyond the scope of this paper to give a full inventory of morphospecies for this exceptionally diverse and well-preserved assemblage, but remains are dominated by medullosan pteridosperms and include pinnae ofMacroneuropteris scheuckzeri with cyclopterid pinnules, Neuropteris ovata, and trunks with downwardrecurved petioles.
Numerous modified proximal pinnules occur at the base of the arms (Fig.
The great variability in spines size and pinnules arrangement seems to be a common feature in the order Antipatharia; therefore, a large number of measures in several specimens from diverse localities, are necessary to verify the variability of a species character.
Rhizome not elongated (internodes indiscernible due to closely overlappiingnodes), leaves clustered near apex; pinnules near middle of blade not dissected to midrib (pinnatifid); bulblets often present (found on the underside of leaf); leaf blades usually widest near base.
Leaves pubescent to densely tomentose; pinnules pinnatifid to pinnate.
Acrossota is, however, unique among octocorals in lacking pinnules on the tentacles (Alderslade and McFadden, 2007), an apomorphy that is not shared with clavulariid sp.
Terminal pinnules (leaflets) 6 to 15 times longer than wide, undersurface of leaflets (abaxial axes) remotely pilose to glabrous P.