Marina minutiflora (Rose) 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.

Family

Fabaceae

Scientific Name

Marina minutiflora (Rose) Barneby

Type

based on Parosela minutiflora (tiny- flowered) Rose, Contrib. U. S. Nat. Herb. 8: 306. 1905. - "Collected by Mr. G. C. Pringle near Yautepec, Morelos, 1902 (no. 8721)." —Holotypus, US! isotypi, GH, NY, OKLA, TEX!— Dalea minutiflora (Rose) Bullock, Kew Bul

Synonyms

Parosela minutiflora Rose, Dalea minutiflora (Rose) Bullock

Description

Species Description - Slender, erect, obligately annual herbs from a slender, orange taproot, glabrous throughout, 1-5 (6) dm tall, effusely and repeatedly branching upward to form broadheaded or umbraculiform plants, the subcapillary terminal branchlets all floriferous, the main stems green, purple, or stramineous, minutely and distantly microtuberculate, the foliage bicolored, the membranous leaflets bright green above, pallid and minutely punctate beneath, lineolate both sides, the margins gland-crenulate; leaf- spurs almost 0; stipules submembranous, subulate-attenuate or -caudate, 0.5-1.5 mm long, fimbriolate at base; intrapetiolular gland spiculiform; post-petiolular glands prominent, conic or prickle-shaped; main cauline leaves 1.5-3 (3.5), exceptionally up to 7 cm long, shortly petioled, with mostly 8-13 (rarely fewer) pairs of oblong, ob- long-oblanceolate, or narrowly obovate, obtuse or commonly openly retuse, bluntly gland-mucronate, flat leaflets 3-9 mm long, the rameal leaves shorter, with mostly 3-7 pairs of smaller leaflets;peduncles both leaf-opposed and terminal to branchlets, (1) 3-20 mm long; racemes very loosely or remotely (1) 2-6 (9)-flowered, the axis becoming (0) 3-12 (20) mm long; bracts early caducous from small decurrent spurs, spatulate or flabellate, 0.8-1.1 mm long, marginally fimbriolate; pedicels filiform, up to 1 mm long, 2-glandular at apex; calyx 2.1-2.7 (3) mm long, the shallowly obconic- campanulate tube 1.3-1.6 mm, not pleated, the ribs slender but prominent, the flat intervals charged with 3-6 small, uniseriate, golden glands, the teeth subequal, the dorsal one ovate-deltate, 0.9-1.4 mm long, the ventral pair slightly shorter and broader, united nearly half their length behind the banner; petals bicolored, the blade of banner opening whitish (often with purple basal lobes) early rubescent, eglandular, the inner petals vivid magenta-purple, also eglandular, perched 1.1-1.5 mm above hypanthium rim; banner 1.8-2.4 mm long, the claw 0.7-1.2 mm, the subcircular, entire or shallowly emarginate blade 1-1.5 mm long and about as wide, united across the top of claw to form a shallow comet; wings 2.3-2.7 mm long, the claw 0.1-0.3 mm, the oblong-obovate blade 2-2.7 mm long, 1.3-2.4 mm wide; keel 2.2-3.5 mm long, the claws 0.4-0.8 mm, the broadly obovate blades 1.8-3.2 mm long, 1.3-2.4 mm wide; androecium 10-merous, 3.3-4.2 (5.2) mm long, the longer filaments free for ± 0.7 mm, the connective gland-tipped, the bluish anthers 0.25-0.35 mm long; pod 1.7-2 mm long, subglobose beyond the short, inversely conic base, slightly compressed, nutlike, crested ventrally above the pore, the style-base lateral, neither keeled dorsally nor prowed across the top, the valves firm distally, charged on each face with ± 20-30 small, firm subcontiguous glands up to 0.2-0.4 mm diam.— Collections: 11 (ix).

Distribution and Ecology - Brushy and grassy hillsides, commonly in shade of shrubs, apparently always on limestone, local but forming dense, colonial populations, about the e. edge of Balsas Depression in Morelos, Puebla, and adjoining Guerrero, in Puebla extending e. just into the upper margin of the Tehuacan desert; somewhat disjunct in s.-w. Oaxaca. — Flowering October to January.

Discussion

(Plate XXVI)

Other than M. scopa, this species and the closely related M. stilligera are the only fully glabrous, annual members of the genus. They differ collectively from M. scopa in their small stature (1-5, rarely 6 dm, not 5-15 dm tall), their small flowers (calyx 2-3, not 3-4 mm long), and in the peltate blade of the banner which is recessed above the top of the claw into a little conic pit. Both species are notable for the extreme delicacy of all their parts.

In general aspect M. minutiflora and M. stilligera are similar and the more important differential characters require close observation. In M. minutiflora the blade of the banner is suborbicular in outline, only shallowly emarginate, and glandless (rarely a minute remnant of a subapical gland) and the pod is charged all over with small, firm-skinned blister-glands which do not break under pressure and are crowded together to present a continuously bullate surface. In M. stilligera the blade of the banner is ovate or spadeshaped, deeply retuse at the apex and charged with one large subapical gland and several smaller ones near the middle, while the pod is charged with fewer and larger, mutually distant, fragile glands which burst under pressure and stain drying papers with orange blots. Flowers and pods of these two types are, so far as known, neatly correlated ecologically, M. minutiflora being strongly and apparently obligately calciphile, whereas M. stilligera has been found only on volcanic bedrock, commonly in pedregal. Strong differential tendencies, but not quite exclusive, are also noted in the foliage and raceme, the main cauline leaves of M. minutiflora having on the average more numerous (8-13 not 6-9) pairs of leaflets but the racemes fewer (mostly 2-6 not 4-12) flowers less crowded along the axis. The ranges of M. minutiflora and M. stilligera overlap only in Morelos, where recent lava-flows overlying and interfingering with limestone bedrock permit the two species to occur in close proximity without actually mingling. It appears that the calcifuge M. stilligera tolerates somewhat higher rainfall and elevations than its relative.

Distribution

Oaxaca Mexico North America| Puebla Mexico North America| Oaxaca Mexico North America| Mexico North America|