Hoffmannseggia Cav., Icon. 4: 63. 1798

Gagnon, Edeline, Bruneau, Anne, Hughes, Colin E., de Queiroz, Luciano Paganucci & Lewis, Gwilym P., 2016, A new generic system for the pantropical Caesalpinia group (Leguminosae), PhytoKeys 71, pp. 1-160 : 68

23. Hoffmannseggia Cav., Icon. 4: 63. 1798 Figs 34F-H , 37

Larrea Ortega (1797), nom. rejec. against Larrea Cav. (1800) in the Zygophyllaceae .

Moparia Britton & Rose (1930).

Type.

Hoffmannseggia falcaria Cav., nom. illeg. = Hoffmannseggia glauca (Ortega) Eifert.

Description.

Perennial woody herbs, most species forming a basal rosette, or subshrubs to 3 m, unarmed, often arising from bud-bearing and tuberous roots, shoots pubescent and with gland-tipped trichomes. Stipules not seen. Leaves alternate, bipinnate, ending in a pair of pinnae plus a single terminal pinna (except for Hoffmannseggia aphylla ); pinnae opposite, in 1-13 pairs; leaflets small and numerous, in 2-15 (- 18) pairs per pinna, glabrous to pubescent, and glandular. Inflorescences terminal or axillary racemes; bracts often caducous. Flowers bisexual, zygomorphic; calyx comprising a hypanthium and 5 sepals, these weakly imbricate, persistent as pods mature (except in Hoffmannseggia microphylla and Hoffmannseggia peninsularis , where they are not always persistent); petals 5, free, yellow to orange, the median petal often with red markings; stamens 10, free, filaments pubescent; ovary glabrous to pubescent, eglandular to glandular, stigma apical, concave. Fruit a laterally compressed, straight or sometimes falcate pod, the sutures almost parallel, papery to leathery, glabrous to pubescent, eglandular or with glandular trichomes, indehiscent or dehiscent, with twisting valves. Seeds compressed, ovoid.

Geographic distribution.

Hoffmannseggia comprises 25 taxa in 23 species and occupies a classical amphitropical distribution in the New World with 10 species restricted to North America (southern USA and Mexico), 12 in South America (Peru, Bolivia to south-central Argentina and Chile, mainly Andean), and one species ( Hoffmannseggia glauca (Ortega) Eifert) widespread throughout the range of the genus.

Habitat.

Subtropical desert and semi-desert grassland, often in open areas and on disturbed sites, on sandy, rocky or calcareous soils.

Etymology.

Named by Cavanilles for the German botanist, entomologist and ornithologist, Johann Centurius Graf von Hoffmannsegg (1766-1849).

References.

Britton and Rose (1930, under Larrea and Moparia ); Burkart (1936); Macbride (1943, under Caesalpinia ); Ulibarri (1979, 1996); Simpson (1999); Simpson et al. (2004, 2005); Lewis (1998, see Caesalpinia pumilio : 171-173); Simpson and Ulibarri (2006); Lewis and Sotuyo (2010).

Notes.

A complete synopsis and key to species (except Hoffmannseggia aphylla ) is available in Simpson and Ulibarri (2006). A list of accepted species is given below excluding types and synonymy, for which the reader should refer to Simpson and Ulibarri (2006).

Figures

Figure 34. Balsamocarpon brevifolium Clos. A branch with inflorescence and fruit (M. F. Gardner, Chile, Gardner & Knees 5825 (E )) B fruits with persistent calyx, C habit (P. Baxter, Chile, Baxter et al. DCI 1859 (E )). Zuccagnia punctata Cav. D flowers E fruits (I. Specogna, Flora mendocina (http: // www. floramendocina. com. ar /), Mendoza, Argentina, unvouchered). Hoffmannseggia arequipensis Ulibarri F fruits with persistent calyx, and inflorescence (C. E. Hughes, Arequipa, Peru, Hughes et al. 2342 (FHO )). Hoffmannseggia minor (Phil.) Ulibarri, G habit and inflorescence (G. P. Lewis, Bolivia, unvouchered). Hoffmannseggia humilis (Mart. & Galeotti) Hemsl. H fruit with persistent sepals (J. Neff, Puebla, Mexico, unvouchered). Stenodrepanum bergii Harms I habit J inflorescence K fruit (R. H. Fortunato, Argentina, Fortunato 9144 (BAB )).

Figure 37. Hoffmannseggia pumilio (Griseb.) B. B. Simpson. A habit B median leaflet undersurface C calyx opened out D median petal E detail of glands on dorsal surface of median petal F lateral petal G, H stamens I gynoecium J stigma K detail of glands on ovary L fruit M gland on fruit. A, L-M from Cabrera 30150 B-K from Venturi 8309. Drawn by Eleanor Catherine.