Frankeniaceae Desv.

Milliken, W., Klitgard, B. and Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics. http://creativecommons.org/licenses/by/3.0

Morphology General Habit

Shrubs or subshrubs, evergreen or woody perennials of low stature, usually halophytic or gypsophilous with salt glands and often with simple, unicellular indumentum on stems, leaves and calyces.

Morphology Leaves

Leaves up to 14mm in length, simple, opposite, decussate, sclerophyllous and ericoid, occasionally succulent, blade margins slightly to strongly revolute, sometimes fringed with short, soft trichomes, leaf sheath extending along petiole margins when petiolate, decussate when sessile, midvein inconspicuous to prominently abaxially raised; without stipules.

Morphology Reproductive morphology Inflorescences

Inflorescence terminal, sometimes axillary, solitary or in few-to many-flowered dichasia; bracteoles 2 and often with 2 additional bracts, these often basally connate, subtending flowers, leaf like; peduncles usually absent

Morphology Reproductive morphology Flowers

Flowers actinomorphic, usually bisexual or rarely unisexual then gynodiocecious, sessile; calyx synsepalous, tubular, 4-5 (-6)- lobed, strongly ribbed; petals 4-5(-6), free, clawed; ligule or scale-like appendage present ad axillary at petal base; androecium with 3-6(-8) stamens, anthers often orange-red (3-5 staminodes present in pistillate flowers of F. triandra J. Remy); gynoecium with superior ovary, 3 united carpels, 1 locule, the style filiform with 3 branches; placentation basal - parietal, ovules (1-)3(-many)

Morphology Reproductive morphology Fruits

Seeds 1-8(-40) per fruit . Fruits glabrous, papery, loculicidally dehiscent capsules, surrounded by persistent calyx, brown to golden brown, white or yellow

Diagnostic

Key differences from similar families: Differs from Plumbaginaceae in having: Revolute leaves. Pedicels absent. Ligule-like appendage present adaxially at petal base. 1-3 carpels. Halophytic (gypsophilous in F. gypsophila). Bisexual (unisexual in F. triandra forms dense hard cushions only a few cm high). triandra - gynodiocecious). Dwarf, evergreenhabit (F. Dwarf, evergreenhabit (F. Petiolate (except in F. gypsophila). Peduncles absent (except F. chilensis) Bracteolate; bracteoles 2 and distinct (F. triandra). triandra), or often 2 with 2 additional bracts, these often basally connate, subtending the flowers and leaf like. Calyx synsepalous and tubular (or campanulate to urceolate in F. triandra). Fruit white or yellow (brown to golden brown F. chilensis). Distinguishing characters (always present): Salt glands present on stems, leaves and calyces. Leaves opposite and decussate. Revolute leaf blades. Pedicels absent. Petals clawed. Filiformstyle with 3 branches. Carpels 3. Fruits with persistentcalyx. Foliage with a sweet musky odour.

Distribution

Native. Frankenia chilensis Presl: coastal areas of S Peru and N Chile, saline conditions. F. triandra: an inland species, also found in S Peru and N Chile, NW Argentina and the Puna of Bolivia at 3,350-4,800m. Two further species are found just outside the floristic area but are nonetheless worthy of a mention; F. gypsophilia I. M. Johnst: Chihuahuan Desert in sections of Nuevo León, San Luis Potosí and Zacatecas, Mexico at 1,600-2,200 m. Restricted to gypseous soils. F. margaritae Medrano: endemic and a dominant species of Nuevo León, found at 1,900m.

Note

"Known as the ""Revolver flowers"" due to the prominent ligules which project inward, dividing the inner portion of the flower into separate compartments. Frankenia was named after J. Franke, professor of botany at Uppsala." Number of genera: One genus Frankenia L.with two Neotropical and two Mexican species. Notes on delimitation: Currently placed in the non-core Caryophyllales as sister family to the non-Neotropical Tamaricaceae (APG II, 2003) with which they share many similarities including capsular fruit and a straight embryo.  Placed in the Violales by Cronquist, who recognized a third genus Anthobryum Phil. (= F. triandra) along with Frankenia L. and the monotypicHypericopsis Boiss. which occurs only in Southern Iran.