Severinia

Synonyms

Helie M. Roem. (sec. Swingle and Reece 1967)

Cultivar or taxon

Atalantia Corrêa (sec. Bayer et al. 2009); Severinia Tenore (sec. Swingle and Reece 1967; sensu Tanaka sec. Cottin 2002)

Description

Crown compact or dense, not weeping. First-year twig surface pubescent; second- or third-year twig surface mottled; thorns straight; prickles absent or not persistent. Petiole glabrous, length short; wings absent. Leaflets one, margin crenate/crenulate or bluntly toothed, shade leaflet blades flat or weakly conduplicate, sun leaflet blades flat or weakly conduplicate. Scent of crushed leaflets sweetly orange-like or not scented. Fruit broader than long, as broad as long, or longer than broad; rind black, medium green (4), light green with some break to yellow (5), or green-yellow (6); rind texture smooth (1-3); firmness membranous; navel absent; flesh green/greenish.

Swingle and Reece (1967) provided the following additional notes on the genus:

"Severinia has six species, all with simple leaves and with a cup-shaped disk in which the base of the ovary is partially immersed. The very primitive pulp-vesicles are peripheral and much like those of Hesperethusa..."

"Leaves simple, conspicuously parallel-veined, with very short wingless petioles 1/15-1/10 the length of the leaf blade, not articulated with it; flowers small; in simple clusters in the leaf axils or in corymbs or panicles; sepals 3-5-lobed; petals 3-5; stamens 6-10, free; disk cup-shaped, enclosing the base of the ovary; ovaries with 1-5 locules, with 1 ovule pendent in each locule; fruits small, berry-like and juicy or semidry with a well-defined peel dotted with oil glands; locules with rudimentary pulp-vesicles, polyhedral through mutual pressure, often crushed by the developing seeds; seeds smooth, plump, single in each locule.

The types [sic] species and all the other species here referred to as Severinia have in recent decades been considered to be species of Atalantia. Atalantia, however, differs decidedly from Severinia in having well-formed, conical pulp-vesicles and much larger flowers, often with the filaments of the stamens more or less connate. The typical species of Severinia have the ovary more or less sunken in the disk, which is, in consequence, usually broader than the ovary.... Severinia has very primitive, stalkless, peripheral pulp-vesicles very like those of Hesperethusa; in neither genera is there indication of the contents breaking down into a more or less resinous mass, such as is seen in Pleiospermium. Severinia differs decidedly from Hesperethusa in having simple leaves and wingless petioles. The leaves of Severinia are strongly veined, the finer veins forming more or less uniform reticulations, not clearly marked in Hesperethusa A still more striking difference is in the disk, which is cup-shaped in Severinia and annular in Hesperethusa. Severinia resembles Atalantia in the shape, size, and venation of its leaves and in having wingless petioles, but differs decidedly in having nonarticulated petioles and more primitive pulp-vesicles without definite form, those of Atalantia being conical and pointing toward the center of the fruit with a rather broad base, more or less sunken in the tissues of the dorsal locular walls. Severinia also resembles somewhat several of the genera in the subtribe Triphasiinae, especially the genera Paramignya and Pamburus, from which it differs in possessing rudimentary pulp-vesicles.

Severinia lauterbachii is very different from the first five species of the genus and is as yet only imperfectly known.

Severinia buxifolia and S. disticha are known to have served as rootstocks for Citrus, and it is probable that other species can be so employed."

References

Bayer, R.J., D.J. Mabberley, C. Morton, C.H. Miller, I.K. Sharma, B.E. Pfeil, S. Rich, R. Hitchcock, and S. Sykes. 2009. A molecular phylogeny of the orange subfamily (Rutaceae: Aurantioideae) using nine cpDNA sequences. American Journal of Botany 96: 668–685.

Cottin, R. 2002. Citrus of the World: A citrus directory. Version 2.0. France: SRA INRA-CIRAD.

Swingle, W.T. and P.C. Reece. 1967. The botany of Citrus and its wild relatives. In: Reuther, W., H.J. Webber, and L.D. Batchelor (eds.). The Citrus industry. Ed. 2. Vol. I. University of California, Riverside. http://lib.ucr.edu/agnic/webber/Vol1/Chapter3.html.

Resources

Search for this cultivar in NCBI Entrez or NCBI Nucleotide

           Unifoliolate leaf of  Severinia buxifolia         (Riverside, CA)

Unifoliolate leaf of Severinia buxifolia (Riverside, CA)

           Fruit of  Severinia buxifolia         (Riverside, CA)

Fruit of Severinia buxifolia (Riverside, CA)

           Unifoliolate leaf of  Severinia disticha         (Riverside, CA)

Unifoliolate leaf of Severinia disticha (Riverside, CA)