Codon (genus)

Codon is a small genus of plants from South Africa in the family Codonaceae[1] in the order Boraginales.[2] The genus Codon comprises two species.[3]

Codon
Codon royenii.jpg
Codon royenii
Scientific classification
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Codon

Codon was placed in the Hydrophyllaceae and Boraginaceae.[2] Recent phyllogenetic analysis place it as sister group to the Wellstediaceae and Boraginaceae s.str.[4]

The species of the genus Codon are annual to perennial herbs. The whole plants are densely covered with strong mineralised, unicellular trichomes on cystolithic foot-cells. The plants are growing from strong taproots.[3]

The flowers are tetracyclic and polymerous. The whorls are 10- to 20-merous with a high variability even within one plant individual. Most common are 12-merous flowers. The sepals are free. The petals are fused up to three quarter of their length. The bases of the filaments are fused with the base of the corolla. The fused parts of the filaments form septa. These septa form separate nectar chambers. The gynoecium is superior and consists of two carpels. The base of the gynoecium forms a lobed nectary disc. Each lobe is covered with nectarostomata and secretes nectar in the nectar chambers.[5] The flowers are bell-shaped and white in C. royenii and saucer-shaped and yellow in C. schenckii.

The fruit is an apical-loculicidal capsule.[3][5] Seeds are reticulately sculptured.

SpeciesEdit

ReferencesEdit

  1. ^ Weigend, M.; Hilger, H. H. (2014-10-28). "Codonaceae-a newly required family name in Boraginales". Phytotaxa. 10 (1): 26. doi:10.11646/phytotaxa.10.1.3. ISSN 1179-3163.
  2. ^ a b Luebert, Federico; Cecchi, Lorenzo; Frohlich, Michael W.; Gottschling, Marc; Guilliams, C. Matt; Hasenstab-Lehman, Kristen E.; Hilger, Hartmut H.; Miller, James S.; Mittelbach, Moritz (2016-06-24). "Familial classification of the Boraginales" (PDF). Taxon. 65 (3): 502–522. doi:10.12705/653.5.
  3. ^ a b c Weigend, M.; Hilger, H. H. (2016). Flowering Plants. Eudicots. The Families and Genera of Vascular Plants. Springer, Cham. pp. 137–140. doi:10.1007/978-3-319-28534-4_9. ISBN 9783319285320.
  4. ^ Weigend, Maximilian; Luebert, Federico; Gottschling, Marc; Couvreur, Thomas L.P.; Hilger, Hartmut H.; Miller, James S. (2014-10-01). "From capsules to nutlets—phylogenetic relationships in the Boraginales". Cladistics. 30 (5): 508–518. doi:10.1111/cla.12061. ISSN 1096-0031.
  5. ^ a b Jeiter, Julius; Danisch, Fränze; Hilger, Hartmut H. (2016). "Polymery and nectary chambers in Codon (Codonaceae): Flower and fruit development in a small, capsule-bearing family of Boraginales". Flora - Morphology, Distribution, Functional Ecology of Plants. 220: 94–102. doi:10.1016/j.flora.2016.02.010.