Stauracanthus

Taxonomy

Stauracanthus J.H.F. Link Neues J. Bot. 2(2): 52. 1807.

Subfamily: Faboideae.
Phylogenetic Number: 3.30.24.
Tribe: Genisteae.
Species Studied - Species in Genus: 2 studied; 2 in genus.

Description

Fruit: A legumelegume:
usually dry, dehiscent fruit derived from a single carpel that opens along two longitudinal sutures
; unilocular; 0.8–2.5 cm long; 0.5 cm wide; 2–9 times longer than wide, or length less than twice as long as width; with deciduous androecial sheath; with deciduous corolla; with persistent calyx; with calyx shorter than fruit; without orifice formed by curving of fruit or fruit segments; straight; not plicate; not twisted; asymmetrical; linear, or oblong (to linear); with 1 straight and 1 curved suture, or both sutures nearly straight; widest near middle or D-shaped (somewhat); not inflated; compressed; without beak; rounded at apex; aligned with longitudinal axis of fruit; short tapered at base; oblique with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally invisible; margin not constricted; margin without sulcus; margin plain; wing(s) absent; nonstipitate; with all layers dehiscing; splitting along suture(s). Dehiscence of valves along both sutures; assumed apical and down; passive. Replum invisible. Epicarp dull; monochrome; reddish brown; with surface texture uniform; glabrous, or pubescent but soon deciduous; with hairs appressed; with 1 type of pubescence; with pubescence golden (barely: primarily colorless); with pubescence uniformly distributed; with simple hairs; pliable; with hair bases plain; eglandular; without spines; smooth; not veined; not tuberculate; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thin; surface not veined; 1-layered; without balsamic vesicles; without fibers; without reniform canals; solid; coriaceous. Endocarp present; visible; dull; opaque; monochrome; reddish brown; smooth; without adhering pieces of testa; nonseptate; chartaceous; not exfoliating; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 2–6; length oblique to fruit length; neither overlapping nor touching; in 1 series. Funiculus 1 mm long; of 1 length only; flattened; curved. Aril present (but apparently easily knocked off); fleshy; when fleshy topknotlike; entire; covering less than 1/2 of seed; brown, or tan.

Seed: 2.8–3.5 mm long; 2–2.5 mm wide; 1.2–1.8 mm thick; not overgrown; not angular, or angular; asymmetrical; oblong, or rectangular (more or less); compressed; with surface smooth; 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; glossy; not modified by a bloom; colored; monochrome, or streaked and mottled (large or minute); with frequent mottles; with frequent streaks; reddish to greenish brown, or green; with purple overlay; glabrous; smooth; coriaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; visible, or fully concealed; concealed by aril; with faboid split; with the lips of the faboid split the same color as the rest of the hilum; punctiform, or larger than punctiform; 0.3 mm long; with straight outline; oblong; apical at apex of radicle tip and between cotyledon and radicle lobe; recessed; within rim; rim color of testa (or nearly so). Lens discernible; 0.8 mm long; with margins straight, or curved; oblong; oblong; not in groove of raphe; confluent with hilum; mounded; similar color as testa; darker than testa; reddish brown; not within corona, halo, or rim. Endosperm present; 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; not concealing radicle; split over radicle; with lobes; with the interface division terminating at base of radicle; without margins recessed; tan; 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; lobe tip straight; deflexed and parallel to cotyledon length; centered between cotyledons; 1/2 to nearly length of cotyledons. Plumule rudimentary; glabrous.

Distribution

Southwestern Europe and northwestern Africa.

Old World; southwestern Europe to Mediterranean to Africa (northwestern).

Tribal Notes

Tribe Genisteae

Traditionally this tribe has been called Genisteae. Reveal (1997) reported that the name Cytiseae was published before the name Genisteae. Following the International Code of Botanical Nomenclature (Greuter et al., 1994), the oldest name for a taxon must be used, so Reveal suggested that this tribe should be called Cytiseae. In 1999 Reveal (1999) reversed himself, so that this tribe remains the Genisteae. Bisby (1981) summarized tribe Genisteae, following the excellent study by Polhill (1976). Bisby correctly noted that "many species have been moved from one genus to another several times and the Cytisus-Genista complex has gained a reputation as a critical group." He continued with an indepth analysis of the tribe. Polhill (1994a, 1994b) and Van Wyk and Schutte (1995a), using chemical and morphological characters, transferred five genera from Crotalarieae (27) to Genisteae: Anarthrophyllum (30.06), Argyrolobium (30.03), Dichilus (30.02), Melolobium, and Sellocharis (30.07). Cristofolini (1997) carried out a cladistic study of the tribe's biogeography, and discussed its early evolutionary history. López et al. (2000) studied the species of this tribe occurring in southwestern Spain and presented detailed descriptions for and a key to them.