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!Tritonia securigera (Aiton) Ker Gawl. Search in The Plant ListSearch in IPNISearch in Australian Plant Name IndexSearch in NYBG Virtual HerbariumSearch in Muséum national d'Histoire naturelleSearch in Type Specimen Register of the U.S. National HerbariumSearch in Virtual Herbaria AustriaSearch in JSTOR Plant ScienceSearch in SEINetSearch in African Plants Database at Geneva Botanical GardenAfrican Plants, Senckenberg Photo GallerySearch in Flora do Brasil 2020Search in Reflora - Virtual HerbariumSearch in Living Collections Decrease font Increase font Restore font
 

Published In: Annals of Botany, Koenig & Sims 1: 228. 1804. (Ann. Bot. Koenig & Sims) Name publication detail
 

Project Name Data (Last Modified On 6/6/2016)
Acceptance : Accepted
Taxon Profile     (Last Modified On 10/13/2016)
Description: Plants (100–)150–250(–350) mm high. Corm subglobose, 10–20 mm diam.; tunics of fine-textured or wiry fibres, sometimes thickened into flattened claws at base. Stem suberect or flexed outward above uppermost sheath, usually unbranched, rarely with 1 branch from near base. Leaves 4–8, linear-lanceolate to lanceolate, suberect or spreading in a 2-ranked fan, usually ± 1/2 as long as stem, (40–)80–200 (–250) × (4–)6–10(–12) mm wide, acute to acuminate, main vein moderately thickened, margins slightly thickened, uppermost cauline leaf membranous, bract-like, sheathing, sometimes concealed by uppermost foliage leaf. Spike suberect, moderately lax, subsecund, 2–15-flowered; bracts dry-membranous, translucent flushed brown and speckled in upper half, 7–10(–12) mm long, minutely 3- or irregularly toothed, inner ± as long, shortly bifid. Flowers zygomorphic, orange or apricot with yellow throat and yellow spot on lower tepals surrounding callus; perianth tube obliquely funnel-shaped, (10–)12–15(–20) mm long, lower cylindric portion 3–6(–15) mm long, widening to 6–8 mm diam.; tepals unequal, obovate, dorsal larger, slightly hooded over anthers, often paler inside, upper laterals spreading, lower tepals deflexed, upper tepals 10–15(–20) × 7–15 mm, lower (10–)12–15 × 5–8 mm, each with a quadrate yellow callus 2–4 mm high near base. Filaments unilateral, arcuate, 9–12(–15) mm long, exserted up to 6 mm; anthers (4–)5–6 mm long, often curved, violet. Style dividing opposite or beyond anthers, branches 4–6 mm long. Capsules ellipsoid, 7–10 mm long. Flowering time: late August to October or November.
Country: South Africa
South African Province: Eastern Cape, Western Cape
Distribution and ecology: extending through southern Western Cape near Ladysmith and Mossel Bay eastward through the Little Karoo and southern Cape to Adelaide and Somerset East in Eastern Cape; on stony flats in renosterveld and karroid shrubland.
Diagnosis: the central species in a taxonomically difficult group characterised by similar two-lipped, orange flowers with an obliquely funnel-shaped tube conspicuosly yellow in the throat and about as long as the tepals (sometimes slightly longer), the lower tepals each with a yellow blotch near the base bearing a quadrate or axe-like callus 1–4 mm high. Within this group, Tritonia securigera is applied to plants with plane, lanceolate or linear-lanceolate leaves, usually forming an erect fan up to half as long as the stem, the main vein raised and the margins thickened and without prominent submarginal veins. The perianth tube is usually 10–15 mm long, with the narrow basal portion 3–6 mm long. Plants from Kommadagga are variable in tube length, the tube in some individuals up to ± 20 mm long with the narrow basal portion 15 mm long. Introgression with T. chrysantha may be indicated here.

Tritonia nelsonii from Gauteng, Limpopo and Northwest is usually taller with narrow, stiffly erect leaves with numerous prominent veins; T. strictifolia from interior Eastern Cape around Grahamstown is distinguished by prominent submarginally veined leaves; and T. laxifolia from Eastern Cape and tropical Africa flowers in late summer and autumn and has larger capsules 12–15 mm long closely appressed to the stem. Two other taxa are less clearly separated: T. parvula from the central and eastern Little Karoo is a mostly smaller plant with linear leaves, mostly 1–2(–3) mm wide; and T. watermeyeri from the western Little Karroo has more or less spirally twisted leaves with the margins often undulate or crisped.


 


 

Specimens whose coordinates are enclosed in square brackets [ ] have been mapped to a standard reference mark based on political units.
 
 
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