Codonaceae (Retief & A.E.van Wyk) Weigend & Hilger

Weigend, Maximilian & Hilger, Hartmut H., 2010, Codonaceae-a newly required family name in Boraginales, Phytotaxa 10, pp. 26-30 : 27

Codonaceae (Retief & A.E.van Wyk) Weigend & Hilger , fam. & stat. nov.

Basionym: Boraginaceae subfam. Codonoideae Retief & A.E.van Wyk (2005: 79) . — Type: Codon L., generic type species: Codon royenii ( Linnaeus 1767: 292) .

Subperennial or perennial, densely branched, spiny shrublets. Strong taproot present. Stems terete, erect. Indumentum of white spines consisting of 3–12 cystolithic foot cells, stiff, unicellular trichomes and 2–5- celled, uniseriate, gland-tipped trichomes. Leaves alternate, estipulate, entire, petiolate, petioles stiffly curved towards shoot apex and lamina held +/- parallel to shoot axis, lamina (narrowly) ovate with acuminate apex and rounded base, margin entire to coarsely serrate, adaxially densely spiny, abaxially with spines only on the very prominent midvein, venation pinnate with lateral veins ascending. Inflorescence frondose-bracteose, initially scorpioid, later straight monochasia, rarely reduced to a single terminal flower. Flowers erect, with 10–20 perianth elements, actinomorphic, bisexual, hypogynous. Calyx divided nearly to base, calyx lobes unequal in width, narrow and wide calyx lobes alternating, densely spinose and pubescent. Corolla white or yellow, sympetalous, campanulate to saucer-shaped, lobes half-erect to spreading, oblong with rounded apex, inside with 6–10 flap-like protrusions near filament bases. Stamens 6–10, filaments basally pubescent, epipetalous, inserted ca. 1/5 th from the base of the tube, incurved and closing the tube near base, then erect, anthers dorsifix, exserted. Ovary bicarpellate, nearly two-locular by deeply intruding placentae, style terminal, divided into two long stigmatic lobes for ca 1/2 of its length. Fruit a dry, bivalved capsule, loculicidal, seeds numerous, ellipsoidal to ovoidal, testa with deeply reticulate epidermis cells. Endosperm copious.

This new family consist only of the genus Codon with two species, Codon schenckii Schinz (1884: 173) and C. royenii Linnaeus (1767: 292) in Southwest Africa ( Republic of South Africa and Namibia). Codon royenii has been typified by Jarvis et al. (1993), but for Codon schenckii several syntypes are available ( Friedrich-Holzhammer 1967b). A recent, critical revision of the genus is not available, only the cursory treatment in Friedrich-Holzhammer (1967b) for Namibia.