Wisteria

Taxonomy

Wisteria T. Nuttall Nom. cons. Gen. 2: 115. Mai (sero)-Jun (prim.) 1818.

Subfamily: Faboideae.
Phylogenetic Number: 3.7.
Tribe: Millettieae.
Species Studied - Species in Genus: 6 studied; 6 in genus.

Description

Fruit: A legumelegume:
usually dry, dehiscent fruit derived from a single carpel that opens along two longitudinal sutures
; unilocular; 7–20 cm long; 0.8–1.6 cm wide; 0.6–1 cm thick; 2–9 times longer than wide, or more than 9 times longer than wide; with deciduous androecial sheath; with deciduous corolla; with deciduous calyx; without orifice formed by curving of fruit or fruit segments; straight; not plicate; not twisted; symmetrical, or asymmetrical; linear, or oblanceolate, or obliquely oblanceolate; with both sutures nearly straight, or both sutures parallelly curved; not inflated; compressed; with beak, or without beak; straight; with solid beak the same color and texture as fruit; tapered at apex, or short tapered at apex; aligned with longitudinal axis of fruit; long tapered at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; chartaceous, or coriaceous; seed chambers externally visible, or invisible; seed chambers with the raised seed chambers not torulose; margin constricted, or not constricted; margin slightly constricted along both margins; margin without sulcus; margin plain; wing(s) absent; nonstipitate; with all layers dehiscing; splitting along suture(s). Dehiscence of valves along both sutures; apical and down; active; with valves twisting. Replum invisible. Epicarp dull; monochrome; brown; with surface texture uniform; glabrous, or pubescent and indurate; with hairs appressed; with 1 type of pubescence; velutinous; with pubescence brown; with pubescence uniformly distributed; with simple hairs; stiff; with hair bases plain; eglandular; without spines; smooth, or not smooth; with elevated features; not veined; not tuberculate; minutely rugose; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thin; surface not veined; 3-layered; without balsamic vesicles; without fibers; without reniform canals; with spongy layer over vitriol over solid layer, or solid layer over vitriol layer over solid layer; coriaceous, or chartaceous. Endocarp present; visible; dull; opaque; mottled; white; with mottling more or less uniform; with brown overlay; pithy, or smooth; without adhering pieces of testa; septate, or nonseptate; with septa thicker than paper, firm; with septa eglandular; chartaceous, or pulpy; not exfoliating; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 1–8; length parallel with fruit length; neither overlapping nor touching; in 1 series. Funiculus 1–1.5 mm long; of 1 length only; thick; straight, or triangular. Aril present; dry; when dry rim-aril and tongue-aril, or partial rim-aril; entire; tan, or white.

Seed: 7–20 mm long; 5–19 mm wide; 2.5–7 mm thick; not overgrown; not angular; symmetrical, or asymmetrical; oblong, or obovate, or reniform; terete, or compressed, or flattened; with surface smooth; with visible radicle and cotyledon lobes, or without visible radicle and cotyledon lobes; without external groove between radicle and cotyledon lobes; with shallow 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, or glossy; not modified by a bloom; colored; mottled; with frequent mottles; brown; with brown overlay (darker); glabrous; smooth, or not smooth; with elevated features; rugose; chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe visible, or not visible; from hilum through lens and terminating before base of seed; not bifurcating; darker than testa; raised. Hilum present; partially concealed; concealed by aril; with faboid split; with the lips of the faboid split the same color as the rest of the hilum; larger than punctiform; 1.2–4 mm long; with curved outline, or straight outline; elliptic; oblong; apical according to radicle tip but marginal according to seed length; recessed; within halo, or within rim; halo darker than testa; rim color darker than testa. Lens discernible; 0.5–1.5 mm long; with margins straight, or curved; triangular; ovate; not in groove of raphe; confluent with hilum, or adjacent to hilum; 0.5 mm from hilum; mounded; similar color as testa; darker than testa; brown; within rim, or not within corona, halo, or rim; rim color of testa. Endosperm absent. 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; not concealing radicle; notched at radicle; without lobes; with the interface division terminating at base of radicle; without margins recessed; tan to yellow; inner face flat; glabrous on inner face. Embryonic axis oblique to right angled; oblique to length of seed to parallel to length of seed to perpendicular to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; bulbose to linear; lobe tip straight; deflexed and parallel to cotyledon width; centered between cotyledons; less than 1/2 length of cotyledons. Plumule rudimentary, or moderately developed; glabrous.

Distribution

North America, China, and Japan.

New World and Old World; United States; Russia, China, and Japan.

Generic Notes

Rehsonia Stritch (1984) is included in Wisteria because Geesink (1984) maintained its type species in Wisteria.

Tribal Notes

Tribe Millettieae

Geesink (1981) treated this tribe, as others before him, under the tribal name Tephroseae, but we now know that its correct name is Millettieae. Recent tribal studies (Geesink, 1981, 1984; Polhill, 1994a, 1994b) have arranged the genera in alphabetical order without phylogenetic numbers. Geesink (1984) monographed tribe Millettieae, and presented descriptive notes about fruits and seeds and in situ fruit and seed drawings. However, we are not entirely following Geesink (1984) for generic parameters because he either questioned the status of many of his new genera or did not make the necessary species transfers. The few new genera which he clearly recognized are being accepted. Lavin et al. (1998) developed a preliminary infratribal classification of six informal groups using phytochrome nucleotides: Millettia group, Lonchocarpus group, Derris group, Tephrosia group, "primitive" group, and Phaseoleae group. Lavin (1987) transferred Sphinctospermum to Millettieae. Lavin and Doyle (1991) carried out cladistic analyses integrating morphological and chloroplast DNA data, and concluded that it is a member of Robineae where we have placed it (now 8.12).