Mimosa quadrivalvis var. angustata (Torr. & A.Gray) Barneby
-
Authors
Rupert C. Barneby
-
Authority
Barneby, Rupert C. 1991. Sensitivae Censitae. A description of the genus Mimosa Linnaeus (Mimosaceae) in the New World. Mem. New York Bot. Gard. 65: 1-835.
-
Family
Mimosaceae
-
Scientific Name
-
Type
190h. Mimosa quadrivalvis Linnaeus var. angustata (Torrey & Gray) Barneby, comb. nov., based on autonym generated by Schrankia angustata var. brachycarpa Chapman, 1865, q.v. infra. S. angustata Torrey & Gray, Fl. N. Amer. 1:400. 1840.—"S. uncinata [sensu]
-
Synonyms
Schrankia angustata var. brachycarpa Chapm., Schrankia angustata Torr. & A.Gray, Schrankia uncinata Willd., Mimosa microphylla Dryand. ex Sm., Morongia microphylla (Dryand. ex Sm.) Britton, Leptoglottis microphylla (Dryand. ex Sm.) Britton & Rose, Mimosa horridula Michx., Schrankia uncinata Willd., Morongia uncinata (Willd.) Britton, Schrankia angustata var. brachycarpa Chapm., Leptoglottis chapmanii Small, Schrankia chapmanii (Small ex Britton & Rose) F.J.Herm., Schrankia horridula var. angularis Chapm., Morongia horridula var. angularis (Chapm.) A.Heller, Leptoglottis halliana Britton & Rose, Schrankia angustisiliqua (Britton & Rose) F.J.Herm.
-
Description
Variety Description - Leaf-formula (iii-)iv-viii/(9-) 10— 17(— 19); longer lf-stks (6—)7—15 cm, the petiole (1.5-)2-4 cm, shorter than rachis; rachis of longer pinnae (10-)14-42 mm; longer lfts 2.5-7.5 x 0.6-1.7 mm, the venation immersed, either discolored or imperceptible dorsally; peduncles 2-6 cm; capitula without filaments 5-7.5 mm diam.; pod polymorphic in dimensions and armature, either a) elongate, 8-13 cm with long sterile beak, discounting prickles 3-4.5 mm diam., or b) of similar length but only (2-)2.5-3 mm diam., or c) only 4-8 cm long, often more shortly beaked and more densely prickly with basally confluent aculei, the replum (2-)2.2-3.5 mm and the valves (1.7-)2-2.5 mm wide, the whole either glabrous or puberulent; seeds 14-20(-24).
Distribution and Ecology - In open sunny places on sandy or loamy soils of pine-palmetto savanna and mixed deciduous woodland of the coastal plain and piedmont, becoming weedy in fallow ground, along highways, and in waste places, widespread and frequent from far w. Virginia and s.-e. Kentucky to s. peninsular Florida, s.-w. to s. Louisiana and e. Texas (Isely, 1973, map 46, sub Schrankia microphylla, but this excluding the Texan populations shown by Turner, 1939: 46, map 16).—Fl. IV-X, into winter in subtropical Florida.
-
Discussion
Except for nomenclature, contingent on the taxonomy, my concept of var. angustata coincides with Schrankia microphylla sensu Isely (1971a, 1973) except in this respect: I follow Turner (1959) by including Leptoglottis halliana, the lectotype of Schrankia angustata, and similar east-Texan schrankias with leaf-formula of iii— vi/12-18 and long narrow pods, which appear to me indistinguishable from some populations in Florida. These controversial taxa were transferred by Isely to Schrankia latidens, but contradict the contrasting morphological definitions presented in his key and discussion (1971a: 234, 236). There appears to be a narrow gap in the known dispersal of var. angustata in Louisiana between the lower Mississippi and lower Sabine rivers, but this gap cannot outweigh morphological congruence between plants found to the east and west.
The variation in length and armature of the fruit of var. angustata was noted by Chapman, and has given rise to a number of proposed segregates; these, however, as Isely has ably demonstrated, lack geographic patterns, except insofar as the state with short, usually burrlike but sometimes only thinly aculeate pod, is not encountered at the southern and western extremities of the dispersal range. No significant correlation has been found between length, girth, pubescence, and armature of fruit, which vary independently of one another. Occasional plants in Florida have incipiently elevated midrib on back of leaflets, suggesting passage into var. floridana.
-
Distribution
United States of America North America| Texas United States of America North America| Florida United States of America North America| Kentucky United States of America North America| Louisiana United States of America North America| Virginia United States of America North America|