Dalea cliffortiana

  • Title

    Dalea cliffortiana

  • Authors

    Rupert C. Barneby

  • Scientific Name

    Dalea cliffortiana Willd.

  • Description

    18.  Dalea cliffortiana Willdenow

    (Plate XLII)

    Annual herbs, sometimes of long duration, variable in habit and stature, 0.8-7 dm tall, glabrous up to the inflorescence or very thinly and obscurely puberulent distally, the striate-angular, smooth to sparsely punctate or verruculose, stramineous or purplish stems either erect, then either simple and monocephalous or paniculately

    few-branching at and above middle (the branches often surpassing the central axis), or branched from the base, the stems then incurved-ascending or rarely prostrate, the foliage green, the leaflets  ± bicolored, paler and livid-punctate beneath; leaf-spurs up to 1 mm long; stipules 0.8-3 (4) cm long, narrowly triangular-subulate to sublinear, usually purplish; intrapetiolular glands minute; post-petiolular glands small but prominent; leaves (1) 1.5-4.5 (5) cm long, shortly petioled, with margined, commonly livid-punctate rachis and (3) 4-6 (7) pairs of narrowly oblong-oblanceo-late to linear-oblanceolate or -elliptic, subacute or minutely emarginate, distally gland-crenulate, dorsally carinate but flat or only marginally involute leaflets (2) 3-16 mm long, the terminal one elevated beyond and longer than the last pair; peduncles terminal to the main and all lateral axes, subobsolete up to 3 (5) cm long; spikes very densely many-flowered, the flowers crowded together in several to many spirally ascending ranks, ovoid to ovoid-oblong or the largest becoming cylindroid in age, without petals (6) 7-12 mm diam, the pilosulous axis becoming (0.8) 1-5.5 cm long; bracts persistent, lance- or elliptic-acuminate to obovate and abruptly caudate, 3-6 (7) mm long, the body nearly always livid or blackish and glandular-verrucose dorsally toward the middle, pallidly membranous-margined, the lowest (often lacking a flower) glabrate and ciliolate, the rest it densely pilosulous, plumose-ciliate, glabrous within; calyx (3) 3.8-5 mm long, densely pilose or pilosulous, the tube 1.4-2.3 mm long, recessed behind the banner, the ribs slender, commonly livid, the membranous intervals glandless or charged with 1-2 (3) small yellowish glands, the triangular to lance-acuminate or -aristate teeth of nearly equal length, (1.3) 1.7-3.3 mm long, varying from a little shorter to twice longer than the tube; petals normally bicolored, the banner white, faintly rubescent in age, the epistemonous ones most commonly rich, vivid blue, more rarely violet or rose-purple, pink, or exceptionally white, these perched just below separation of the filaments, the keel-blades imbricate in vernation but free; banner 3.2-5 mm long, spatulate, the claw 1.6-3.4 mm long, the oval-ovate blade 1.5-2.2 mm long, 1-1.4 mm wide; wings ± 2-2.5 mm long, the claw very short, the blade broadly oblong 1.3-1.6 mm wide; keel-petals (2.1) 2.4-3.4 mm long, the claw 0.2-0.6 mm, the broadly obovate to suborbicular blade (1.9) 2.1-2.8 mm long, 1.4-1.7 mm wide; androecium 9-10-merous, 4.5-6.7 mm long, the longest filaments free for 1.1-1.9 mm, the connective minutely gland-tipped, the nearly round anthers livid-purple or sometimes pallid, 0.2-0.3 mm long; pod obliquely obovoid or half-obovoid, 2.1-2.6 mm long, the style-base terminal, the valves in the lower ± 2/3 glabrous and hyaline, thinly papery and densely villosulous distally, the prow a little thickened; seed 1.3—1.7 mm long; n = 7 II (Spellenberg, 1973); 2n = 14 (Mosquin).— Collections: 182 (xvi).

    Dry fields, roadsides, waste places, disturbed soil of riverbeds and stream banks, in arid grassland and drought-deciduous thorn-scrub, ascending in open places into the oak-belt, from near sea-level up to 1600 (1950) m (but mostly below 1000 m), widespread and common almost throughout lowland Mexico s.-ward from the Transverse Volcanic Belt, from Nayarit to Veracruz, Oaxaca, and Chiapas, extending n. along the Pacific coastal plain and adjoining foothills of Sierra Madre as far as Rio Mayo in w. Chihuahua (± 28° N) and along the Gulf slope to s.-e. San Luis Potosi (22° N), apparently absent from Tabasco and Yucatan Peninsula; from Mexico abundantly s. through upland and drier regions of Central America to w. Panama; in South America probably adventive but naturalized and locally plentiful especially in the Coastal Cordillera of n. Venezuela (Yaracuy and n. Cohedes to Miranda, with one record from the Orinoco Basin near San Fernando de Apure); coastal Ecuador (near 2° S); naturalized since early XIX century in Islas Filipinas. — Flowering where native from late summer through fall and winter .—Representative: MEXICO. Chihuahua: Gentry 1871 (ARIZ, F, UC). Sinaloa: Shreve 7830 (ARIZ, F). San luis potosi: Purpus 5270 (UC). Durango: Gentry 5275 (ARIZ, NY). Nayarit: Mexia 753 (F, GH, MICH, NY, UC, US). Jalisco: Pringle 2494 (BR, F, GH, M, MICH, NY, SD, W); Ripley & Barneby 13440 (CAS, GH, NY, MEXU, MICH, US). MichoacAn: Hinton 15152 (GH, NY, RENNER, UC). Mexico: Hinton 11501 (F, NY, MICH, UC). Morelos: Ripley & Barneby 14542 (CAS, NY). Veracruz: Purpus 1900 (F, NY, UC, Z). Colima: Palmer 933 (MICH, NY, UC, US). Guerrero: Mexia 8787 (ARIZ, F, NY, UC, US). Oaxaca: Liebmann 4585 (F). Chiapas: Breedlove 7510 (NY, US). GUATEMALA. Chimaltenango: Standley 57951 (F, NY). Chiquimula: Steyermark 31202 (F). Guatemala: Standley 59555 (F). Huehuetenango: Standley 81351 (F). Jalapa: Heyde & Lux 3744 (M). Jutiapa: Standley 60556 (F). Quiche: Standley 6248 (F). Santa Rosa: Standley 77801 (F). Zacapa: Steyermark 29696 (F). EL SALVADOR. Santa Ana: Standley & Padilla 3344 (F). HONDURAS. Choluteca: Molina 23237 (NY). Comayagua: Standley 56241 (F). El ParaIso: Williams & Molina 10684 (F). Lempira: Standley 12988 (F). Morazan: Molina 18459 (NY). Ocotepeque: Standley 27970 (F). Olancho: Standley 17997 (F). Santa barbara: Molina 3779 (F). Valle: Standley 22802 (NY). PANAMA. Herrera: Burch et al. 1301 (NY). VENEZUELA. Merida: Fendler 311 (BR, OXF, K). Yaracuy: Curran 295 (NY). Carabobo: Linden 1518 (F, NY, OXF, W). Aragua: Chardon 173 (US). Distrito Federal: Alston 5252 (NY, US). ECUADOR. Guay as: Svenson 11266 (NY, US). ISLAS FILIPINAS: Cuming 449 (K, L, M); Van Steenis 17878 (L).

    Dalea cliffortiana (George Clifford, 1685-1760, patron of Linnaeus) Willd., Sp. Pl. 3: 1336. 1802, based on Psoralea dalea (former generic name) L., Sp. PI. 764. 1753.— "Habitat in America." + reference back to Dalea L., Hort. Cliff. 363, tab. 22. 1738.— No type-specimen known to survive, the plant in herb. Linn = Dalea leporina (Ait.) Bullock, the holotypus therefore the cited plate in Hortus Cliffortianus! — Psoralea annua Mill., Gard. Diet., Ed. 8 (Psoralea no. 6). 1768, nom. illegit., a superfluous substitute for the cited Ps. dalea L. Dalea linnaei Mchx., Fl. Bor. Amer. 2: 57. 1803, quoad nom. (the plant described also = D. leporina). Dalea annua (Mill.) O. Kze., Rev. Gen. 178. 1891. Dalea annua ß willdenowii O. Kze., Rev. Gen. 178. 1891, evidently based primarily on D. cliffortiana Willd. Dalea dalea (L.) MacMill., Metasp. Minn. Vail. 330. 1892 ("Dalea"). Parosela dalea (L.) Britt., Mem. Torrey Club 5: 196. 1893 ("Dalea"). Parosela cliffortiana (Willd.) Rose, Contrib. U. S. Nat. Herb. 10: 105. 1906 ("cliffortiana"). Thornbera dalea (L.) Rydb. N. Amer. Fl. 24: 120. 1920 ("Dalea").

    Dalea acutifolia (with sharp-pointed leaflets) S. & M. ex DC., Prod. 2: 245. 1825. — "...in Mexici montibus Chilapae humidis [i.e. Guerrero]..." — Holotypus, Caiques Dess. Fl. Mex. Pl. 228! — Specimens of D. cliffortiana distributed by Pavon, probably from the collections of Sesse & Mocino, are extant at BM ("Dalea polystachya sp. nov.") and OXF (see next paragraph); also in Herb. Sesse, No. 2680 (F, MA), as "Dalea antihydrophobica"; some may be isotypic, but cannot safely be cited as such. —Parosela acutifolia (DC.) Rose, Bot. Gaz. 40: 144. 1905.

    Dalea angustifolia (with narrow leaflets) G. Don, Gen. Hist. Diehl. Pl. 2: 223. 1832.— "Native of Mexico...(v.s. in herb. Lamb.)." — Holotypus, labelled originally "Dalea sp. nov. de Mexico", annotated probably by Don "angustifolia", the specimen doubtless acquired by Lambert from Pavon, OXF!

    Amorpha glandulosa (gland-sprinkled) Blanco, Fl. Filip. 555. 1837 ("Glandulosa").—"...mui comun en Angat, y entre Lipa y Tanduan." —No typus known to survive, but the description, already accepted by Merrill, decisive. — Dalea glandulosa (Blanco) Merrill, Philip. Gov. Bur. Lab. Bull. 27: 37. 1905.

    Dalea nigra (black, of the bracts) Mart. & Gal., Bull. Acad. Brux. 101: 43 (in separate 13). 1843. — "Se trouve dans les savanes de Zacuapan [Veracruz] avec le Dalea elata nobis, a 3,000 pieds." — Holotypus, Galeotti 3263, BR (herb. Mart.)! isotypi, BR (herb. Gal.), W, and mislabelled "Cordillere (Oaxaca)", P\—Parosela nigra (Mart. & Gal.) Rose, Contrib. U. S. Nat. Herb. 10: 105. 1906.

    Dalea virgata (rodlike, of the stiff stems) Micheli, Bull. Herb. Bss. 2: 442, Tab. 9. 1894.— "Hab. Costa Rica prope S. Jose et Buenos-Ayres ad vias, leg. Pittier, N. 1462, 3828, 6504." — Not seen at G, perhaps overlooked by inadvertence; isotypus, Tonduz 1462, collected Dec 1, 1889 and distributed by Pittier, BR! paratypus, Pittier 6504, BR! — Thornbera robusta (stout) Rydb., N. Amer. Fl. 24: 121. 1920 (non Dalea virgata Lag., 1816). Parosela dalea var. robusta (Rydb.) Macbr., Contrib. Gray Herb., New Ser. 65 : 22. 1922. Dalea robusta (Rydb.) Cowan, Brittonia 8: 60. 1954.

    Thornbera pumila (dwarf) Rydb., N. Amer. FI. 24: 120. 1920.— "Type collected at Culiacan, Sinaloa, October 5, 1904, T. S. Brandegee..." — Holotypus, US! — Parosela pumila (Rydb.) Macbr., Contrib. Gray Herb., New Ser. 65: 23. 1922. Dalea pumila (Rydb.) Riley, Kew Bull. 1923: 337. 1923.

    Over the greater part of its range D. cliffortiana is the only species of its group and is easily recognized by the combination of a decisively annual root, few (mostly 4-6 pairs), narrow, glabrous leaflets, closely imbricated persistent bracts more or less pallid-margined and externally glandular-warty, and tiny flowers of which only three or four open each day. The epistemonous petals, usually bright blue, more rarely purple or pinkish-lilac, exceptionally white, are extremely fugitive, commonly shed almost as soon as they are carried up on the summit of the androecial column. The little spoon-shaped banner, always white at first but fading pinkish, disjoints at the same time as the inner petals but is held fast by its claw and often persists as a withered tab until the whole calyx falls away in fruit.

    Contrary to what might be expected of a species so burdened with synonymy, D. cliffortiana is not very variable. There are taller and dwarfer forms, and the spikes vary a good deal in thickness, due to variation in length of the bracts and calyces and in number of flowers arranged in each spiral around the receptacle. Due probably to autogamy, the populations are usually homogeneous internally, with the result that when two occur close together, or intermingle marginally, they may often be sorted into categories, giving the impression of distinct races. In the field these can be striking, but the now extensive herbarium record shows that the various modes of variation are not correlated with each other or with geographic dispersal, making taxonomic division of the species impracticable. At low elevations along the Pacific coast of Mexico the prevalent form of D. cliffortiana is characterized by relatively dwarf and slender stature combined with relatively narrow heads of short-acuminate bracts. The extreme in this direction has been segregated as Thornbera pumila, but even in Sinaloa, from which it was described, it does not fully replace the long-bracted and thick-headed form that extends south into Central America and has received the undeserved distinction of Dalea virgata or Thornbera robusta.

    The names D. angustifolia Don, D. nigra Mart. & Gal. and D. glandulosa (Blanco) Merr. were all applied to D. cliffortiana to distinguish the species not from the genuine plant grown at Hartekamp and described in Hortus Cliffortianus, that is the generitypus of Dalea gen. cons., but from the species which long usurped that title, properly known today as D. leporina (Ait.) Bullock. The confusion between these two widely dispersed and common, weedy daleas can be traced back to the earliest interpretations of the Lin- naean canon, partly due to the fact that the plant preserved in Herb. Linnaeanum as Dalea is actually D. leporina. The identity of the plant described by Linnaeus is securely known through the plate in Hortus Cliffortianus and through a specimen preserved by Philip Miller which represents the original introduction from Veracruz. Because these two species have been confounded in so many herbaria and in so many important floras and are still often misidentified in modern collections the following contrasts may be useful:

    1. Leaflets (3) 4-6 (7) pairs; bracts between the flowers persisting until the whole spike falls apart in advanced fruit; epistemonous petals borne at or scarcely below separation of the filaments. 

    ...D. cliffortiana.

    1. Leaflets (of cauline leaves) 8-17 (24) pairs; bracts deciduous at or just before anthesis of the flowers; epistemonous petals borne ± half-way between hypanthium and separation of the filaments (at least 1.2 mm below that point).

    ...D. leporina.