Zornia

Taxonomy

Zornia J.F. Gmelin Syst. Nat. 2: 1076, 1096. Apr (sero)-Oct 1792.

Subfamily: Faboideae.
Phylogenetic Number: 3.14.21.
Tribe: Aeschynomeneae.
Subtribe: Poiretiinae.
Species Studied - Species in Genus: 77 studied; ca. 80 in genus.

Description

Fruit: A lomentloment:
usually dry fruit derived from a single carpel that breaks transversely into one-seeded fruit segments
(or a lomentloment:
usually dry fruit derived from a single carpel that breaks transversely into one-seeded fruit segments
segment); 1.1–1.8 cm long; 0.1–0.35 cm wide; 0.1–0.2 cm thick; more than 9 times longer than wide; with deciduous androecial sheath; with deciduous corolla; with persistent calyx; with calyx longer than fruit, or equal in length to fruit, or shorter than fruit; without orifice formed by curving of fruit or fruit segments; straight to curved (slightly); not plicate; not twisted; asymmetrical, or symmetrical; moniliform; with 1 straight and 1 curved suture, or both sutures parallelly curved; narrowing in several places, resembling Desmodium (3.11.09) fruit; not inflated; compressed; without beak; rounded at apex; aligned with longitudinal axis of fruit; rounded at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally visible; seed chambers with the raised seed chambers not torulose; margin constricted; margin constricted along both margins, or constricted only on 1 margin; margin without sulcus; margin plain, or embellished; margin with prickles; wing(s) absent; nonstipitate; indehiscent. Replum invisible. Lomentloment:
usually dry fruit derived from a single carpel that breaks transversely into one-seeded fruit segments
indehiscent; segments (articles) inconspicuous; segments (articles) 1.2–5 mm long; segments (articles) widest across seed area; segments (articles) with all essentially similar in shape; segments (articles) circular, or D-shaped. Epicarp dull; monochrome (with or without different colored reticulum); brown, or green, or tan, or yellow; with surface texture uniform; glabrous, or pubescent and indurate; with hairs erect; with 1 type of pubescence; pilose, or villous; with pubescence gray, or brown; with pubescence uniformly distributed; with simple hairs, or complex hairs; with plumose hairs, or bristle-like hairs, or setae; pliable; with hair bases plain; antrorse, or retrorse; straight at apex, or hooked at apex, or coiled at apex; glandular, or eglandular; with glandular dots; without spines; not smooth; with elevated features; veined, or not veined; reticulately veined; not tuberculate; glandular dotted; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp absent. Endocarp present; visible; dull; opaque; monochrome; brown; spongy; without adhering pieces of testa; septate; with septa thicker than paper, firm; with septa eglandular; chartaceous; not exfoliating; remaining fused to epicarp; without wings; entire. Seed(s) 1–15; length parallel with fruit length; neither overlapping nor touching; in 1 series. Funiculus of 1 length only; thick; straight. Aril absent.

Seed: 1.5–2.3 mm long; 1–1.5 mm wide; 0.5–0.8 mm thick; not overgrown; angular, or not angular; asymmetrical; elliptic (reniform), or irregular (reniform), or reniform (with or without beak); compressed; with visible radicle and cotyledon lobes; without external groove between radicle and cotyledon lobes; without hilar sinus; without umbo on seed faces; without medial ridge on each face. Cuticle not exfoliating; not inflated; not wrinkled. Testa present; without pieces of adhering epicarp; not adhering to endocarp; free from endocarp; dull; not modified by a bloom; colored; monochrome, or mottled; with frequent mottles, or infrequent mottles; brown (to reddish-brown or purplish-brown), or tan; with red overlay; glabrous; smooth; coriaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; visible; with faboid split; with the lips of the faboid split the same color as the rest of the hilum; punctiform; between cotyledon and radicle lobe; flush; within rim, or within halo; halo lighter than testa; rim color lighter than testa. Lens discernible, or not discernible; with margins curved; 2 circular mounds separated by groove; not in groove of raphe; confluent with hilum (or at least to the hilar rim); mounded; dissimilar color from testa; darker than testa; reddish brown; not within corona, halo, or rim. Endosperm present; thick, or thin; not pluglike and not resembling tip of radicle; covering entire embryo; adnate to testa. Cotyledons smooth; both outer faces convex; both the same thickness; both more or less of equal length; not folded; margin entire 180 degrees from base of radicle; similar at apex; partially concealing radicle; split over radicle; with lobes; with lobes not touching; with the interface division terminating at base of radicle; without margins recessed; yellow; inner face flat; glabrous on inner face. Embryonic axis deflexed; oblique to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; bulbose, or linear; lobe tip straight; deflexed and parallel to cotyledon width, or oblique to cotyledons; centered between cotyledons; less than 1/2 length of cotyledons, or 1/2 to nearly length of cotyledons. Plumule rudimentary; glabrous.

Distribution

Tropical and warm temperate regions of Old and New World.

New World, or Old World; southeastern United States, West Indies, Mexico, Central America, and South America; Argentina, Peru, Brazil, Ecuador, and the Guianas; Africa, Madagascar, Southwest Asia, India, Indochina, China, Japan, Indonesia and the Philippines, Australia, and Macaronesia (Asia (southeastern)).

Generic Notes

Mohlenbrock (1961) monographed the genus and revised his monograph in Mohlenbrock (1962a). Milne-Redhead (1954) treated the African species. Reynolds and Holland (1989) corrected and expanded the Mohlenbrock monograph for the 17 species that occur in Australia.

Tribal Notes

Tribe Aeschynomeneae

Rudd (1981a) recognized four subtribes of Aeschynomeneae: Ormocarpinae V.E. Rudd (genera 3.14.01–3.14.08), Aeschynomeninae (genera 3.14.09–3.14.16), Discolobinae (A.E. Burkart) V.E. Rudd (genus 3.14.17: Discolobium), Poiretiinae (A.E. Burkart) V.E. Rudd (genera 3.14.18–3.14.21), and Stylosanthinae (G. Bentham) V.E. Rudd (genera 3.14.22–13.4.26). Tribal and subtribal placement of Diphysa is based on Lavin (1987; Polhill, 1994a, 1994b), and not on Polhill and Sousa (1981), who placed Diphysa in Robinieae. Bailey et al. (1997), using the chloroplast rpl2 intron and ORF184, suggested that Brya (11.01), Cranocarpus (11.02), Phylacium (11.22), and Neocollettia (11.26) are not members of Desmodieae (11) and that they probably belong in Aeschynomeneae.