Monographs Details: Dalea rzedowskii Barneby
Authors:Rupert C. Barneby
Authority: Barneby, Rupert C. 1977. Daleae Imagines, an illustrated revision of Errazurizia Philippi, Psorothamnus Rydberg, Marine Liebmann, and Dalea Lucanus emen. Barneby, including all species of Leguminosae tribe Amorpheae Borissova ever referred to Dalea. Mem. New York Bot. Gard. 27: 1-892.
Scientific Name:Dalea rzedowskii Barneby
Description:Latin Diagnosis - Dalea rzedowskii (Jerzy Rzedowski) Barneby, sp. nov., quoad calycem extus glabrum brevidentatum D. hegewischianae haud absimili forsan (sed haud proxime) affinis, sed bracteis persistentibus ac calyce magno sessili multiglanduloso procul recedens. A D. gypsophila Barneby fortasse propriori sed adspectu minus simili calyce brevidentato extus nitide glabro primu visu abhorret. — Herbae procumbentes hinc inde radicantes praeter calycis orem ciliolatum glaberrimae; folia 12-20 mm longa, foliolis 8-10 jugis anguste oblanceolatis 1.5-3 mm longis; spicae laxiusculae breves pauciflorae, floribus 6-15 bractea persistenti lanceolato-acuminata suffultis; calyx ± 5 mm longus, subtumidus, inter costas filiformes immersas grosse sparsim multiglandulosus, dentibus late deltatis tubo multoties brevioribus; petala bicoloria, vexillum albidum, epistemonea roseo-purpurea infra medium androecium insidentia carinae laminis ± 6.5 mm longis. —San Luis Potosi: terrenos margosos con vegetacion de matorral secundario, 1400 m, 5 km al s. de Ciudad del Maiz, oct. 27, 1956, J. Rzedowski 8290. — Holotypus, ENCB.

Species Description - Slender, weakly suffrutescent perennial herbs with arcuately procumbent, apparently tip-rooting, straminous or purplish, prominently gland-verruculose stems up to 6 m long (and probably longer), glabrous up to the internally pilosulous orifice of the calyx, the fine sparse foliage pallid-green or glaucescent, the leaflets smooth above, dotted beneath; leaf-spurs 0.3-0.6 mm long, charged at base with a prominent gland; stipules linear-acuminate, (0.8) 1.1-1.6 mm long, brownish-orange becoming livid, finally dry and fragile; intrapetiolular glands 0 or minute and impressed; post-petiolular glands very prominent, amber- or orange-colored; leaves subsessile, the main cauline ones (drought-deciduous) ± 12-20 mm long, with narrowly margined ventrally grooved, thinly verruculose rachis and ±8-10 pairs of narrowly oblanceolate or (expanded) cuneate-oblanceolate, deeply emarginate, folded leaflets 2-3 mm long, the leaves of axillary spurs and subbasal innovations smaller but otherwise similar, the leaflets (4) 5-8 pairs and ± 1.2-2 mm long; peduncles terminal to the main axes and to some axillary short-shoots, 1-1.5 cm long; spikes shortly but loosely 6—15- flowered, the flowers spreading-ascending, the glabrous axis 4-7 mm long; bracts persistent, narrowly lance-acuminate, firm, livid-glaucescent, 3.5-4 mm long, grossly glandular dorsally and gland-tipped; calyx ±5.1 mm long, broadly oblong-ellipsoid, a trifle tumid, externally glabrous and lustrous, the slender, scarcely prominulous ribs livid-tinted, the broad flat membranous yellowish intervals charged with 6-9 scattered or 2-seriate, hemispherical or ellipsoid, golden blister-glands (larger and smaller), the orifice ciliolate, the broadly low-deltate, externally glabrous, internally silky- pilosulous teeth gland-tipped and -spurred, the dorsal one ± 1 mm long, the rest slightly shorter and broader, the ventral sinus slightly shallower than the others; petals bicolored, the banner whitish with purple basal lobes, the epistemonous ones perched low on the androecium (1.3-1.7 mm above hypanthium), all charged with a linear- elliptic subapical gland, the blade of banner gland-sprinkled; banner =t 8.2 mm long, the claw 3.6 mm, the broadly ovate-cordate, emarginate, hooded blade recessed at base into a shallow comet, strongly recurved out of the calyx, 4.6-5 mm long, 3.6-4 mm wide; wings 8.5 mm long, the claw 2.3 mm, the oblong-elliptic blade 6.7 mm long, 2.1 mm wide; keel 10 mm long, the claws 3.7 mm, the elliptic blades 6.6 mm long, 3.2 mm wide; androecium 10-merous, 9.6 mm long, the longer filaments free for ± 3.3 mm, the connective gland-tipped, the bluish anthers 0.6 mm long; ovary submembranous, thinly pilosulous distally, the pod not seen. — Collections: 1 (typus).

Distribution and Ecology - In second-growth brush on loamy soil, 1400 m (4660 ft), known only from vicinity of Ciudad del Maiz, in s.-e. San Luis Potosi. — Flowering October and November, to be expected also in spring.


(Plate LXV)


Distribution:San Luis Potosí Mexico North America| Mexico North America|

Narratives:Dalea rzedowskii