Aeonium
General Information   |   Species   |   Hybrids   |   Cultivars

x burchardii   (Praeger) Praeger, 1929

Par: Aeonium pseudourbicum  Bañares × Aeonium sedifolium  (Bolle) Pit. & Proust

[Or Aeonium sedifolium  (Bolle) Pit. & Proust × Aeonium urbicum  (Hornem.) Webb & Berthel. when pseudourbicum is included in urbicum.]

Sempervivum ×burchardii  Praeger, Notes on Canarian and Madeiran Semperviva, Transactions of the Botanical Society of Edinburgh 29: 202. 1925 (pro sp.).

Aeonium ×burchardii  (Praeger) Praeger, Semperviva of the Canary Islands area, Proceedings of the Royal Irish Academy 38 Sect.B (1): 465. (24 Sep) 1929 (pro sp.).

Etym: Named for Oscar Burchard (1863-1949).

T: Islas Canarias, Tenerife, Teno Mtns., on the roadside between Masca and Santiago, 800-900m; Jan 1923, Oscar Burchard.

HT: Not cited.

NT: Praeger's analytical sketch, in Praeger, An account of the Sempervivum group: 176, fig. 73. 1932. Designated by Bañares, Vieraea 35: 11. (Oct) 2007 [as LT].

Obs: In Bañares (Vieraea 43: 191, 2015), Art. 40.4 is cited as a reason for a superfluous reneotypification, but that rule applies only to new taxa, while Aeonium ×burchardii (Praeger) Praeger was already validly published.

 

 

Description (according to Praeger, An Account of the Sempervivum Group, 1932) :

An erect glabrous subshrub, 30 cm or more high.

Stem woody, comparatively slender, smooth, often rich brown.

Branches patent, ascending, bare, smooth, with linear leaf-scars, about 6 mm diameter, rich brown and shining in upper part, leafy near the apex.

Leaves crowded, loosely rosulate (in the British climate not rosulate but scattered), obovate-spatulate, 7 - 10 x 2.5 cm, in transverse section oblong-rhomboidal owing to thickening along the nerve, especially on the face, 5 mm thick, broadly cuneate and subapiculate at apex, attenuate and subpetiolate below, the petiole rhomboidal in section ; marginal cilia short, very blunt, rather distant ; surface dark green, shining, glabrous or sparsely hairy on the upper part of the face, more or less brown-lined down the centre.

Flowering branches 12 - 16 cm long, leafy with decreasing oblong-spathulate leaves.

Inflorescence flattish or convex, minutely glandular-pubescent, 7 - 10 x 10 - 15 cm, racemose, with about 6 spreading dichotomous branches, pedicels glandular-pubescent, about 7 (5 - 10) mm long.

Flowers : Buds ovoid, flowers 8-9-parted, 1.5 cm across, buff (in this climate pale yellow), calyx 5 mm long, densely glandular-pubescent, sepals lanceolate, acute or acuminate, 3 mm long, petals lanceolate, acute, 8 - 9 mm long, buff with a red nerve, edges scabrid in the upper part, stamens yellow, the epipetalous 6.5 mm, the episepalous 7 mm long, filaments slightly hairy, scales minute, subquadrate, broader than long, angles rounded, carpels pale yellow, slightly hairy, ovaries 3 mm long, styles 5 mm long.

Flowering time : April.

Cytology : n = 18

Habitat : Canary Islands : Tenerife, by the road from Masca to Santiago, near the north-west corner of the island, 900 - 980 m.



Aeonium ×burchardii from Burchard, Beiträge zur Ökologie und Biologie der Kanarenpflanzen, Bibliotheca Botanica 98: t.31. 1929.



Aeonium ×burchardii LT from Praeger, An account of the Sempervivum group: 176, fig. 73. (Aug) 1932.

 




< back