Senna reticulata (Willd.) H.S.Irwin & Barneby

Authors

Howard S. Irwin, Rupert C. Barneby

Authority

Irwin, Howard S. & Barneby, Rupert C. 1982. The American Cassiinae. A synoptical revision of Leguminosae tribe Cassieae subtrib Cassiinae in the New World. Mem. New York Bot. Gard. 35, part 2: 455-918.

Family

Caesalpiniaceae

Scientific Name

Senna reticulata (Willd.) H.S.Irwin & Barneby

Type

Holotypus, Hb. Willd. 7994, collected by Sieber and acquired from Hoffmannsegg, B (2 sheets, one = F Neg. 1740)!—Chamaesenna reticulata (Willdenow) Pittier, Arb. y Arbust. Legum. II Cesalp. 131. 1928, without bibliographic reference.

Synonyms

Cassia reticulata Willd., Chamaesenna reticulata (Willd.) Pittier, Cassia strobilacea Kunth, Cassia tarantan Kunth, Cassia dumetorum Bertero ex DC., Cassia annunciata E.H.L.Krause

Description

Species Description - Coarse, amply leafy, potentially arborescent shrubs of rapid growth, at anthesis (1-)2-8(-9) m, precociously flowering as a softly woody bush but sometimes becoming a tree with trunk up to 8 cm diam few-branched into an irregular crown, pilosulous-puberulent throughout or almost so with fine erect, incumbent or sinuous hairs up to 0.1-0.5 mm, the vesture of hornotinous branchlets usually composed of erect shorter and longer hairs (the latter sometimes 0), that of the foliage either spreading or subappressed, the lvs ± bicolored, the lfts deep green drying olivaceous, dull on both faces, paler beneath, the racemes at first axillary to developed lvs, later forming an exserted candelabriform panicle. Stipules herbaceous obliquely triangular-lanceolate (5-)6-10 mm, at base dilated on side further from petiole and auriculately amplexicaul, the auricle or the whole blade reflexed in age, the blade strongly parallel-nerved distally, becoming dry and deciduous before the lf. Lvs (2-)2.5-7(-8.5) dm; petiole including the discolored, when dry shrunken pulvinus (2.5-)3.5-13(-16) cm, at middle 2-6(-7) mm diam, terete or faintly 2-ridged ventrally; rachis (1.1-)1.3-4.5(-5) dm, tapering and progressively more trigonous distally, the flat, narrowly margined ventral face of each interfoliolar segment gradually dilated upward, the terminal seta modified into a subcarneous (often eaten) lance-triangular or deltate conduplicate blade 1.5-5 x 1-4 mm; petiolar glands 0; pulvinules (when fresh orange-yellow) 2.5-6 mm; lfts (6-)7-13(-15) pairs, either conspicuously or scarcely accrescent distally (but the proximal 1-3 pairs always smallest), the distal or largest pair oblong, oblong- or exceptionally subrhombic-obovate (6.5-)7- 18(-19) x (2-)3-7(-8.5) cm, 2-3.3 times as long as wide, at apex most commonly broadly rounded mucronulate, less often shallowly emarginate or deltately subacute, at base inequilaterally cuneate or rounded, the margin plane, the straight centric midrib immersed or almost so above, cariniform beneath, the 10-18 pairs of camptodrome secondary veins usually prominulous on both faces, sometimes faintly so above, the tertiary and reticular venulation sometimes finely raised on both, sometimes only on dorsal face, sometimes faint on both. Racemes incurved to vertical many-flowered, in early anthesis capped by a blunt cone of bright yellow or orange-yellow (when dry fuscous) bracts, early and often much elongating, the stout axis including the short peduncle becoming (1-) 1.5-5.5(-6) dm; bracts subpetaloid, amply obovate or rhombic-obovate, abruptly acuminulate (12-) 15-22(-24) mm, minutely but densely puberulent dorsally, caducous as the pedicel begins to lengthen; pedicels at and after full anthesis (3-)4-9(-10) mm; fl-buds obliquely obovoid obtuse, minutely puberulent; sepals subpetaloid, little graduated, oblong-obovate-concave 10-14 mm, often disjointing before the petals; petals glabrous, yellow drying whitish or ochroleucous brown-veined, all conspicuously clawed, the blades little heteromorphic, oblong- obovate or obovate-flabellate, the longest petal (12-) 14-22 mm; androecium glabrous, functionally 2-merous, the filaments of 4 median stamens 1.5-2.5 mm, of 2 latero-abaxial ones thickened and 2.5-5 mm, of the central abaxial one 4-5.5 mm, the anthers of 4 median stamens sterile or almost so, lance-oblong from shortly sagittate base, including the porrect 2-porose beak 3-5 mm, the anther of the centric abaxial one sterile 2.5-4.5 mm, its basal lobes hastately recurved, the 2 large fertile anthers lunately lanceolate in outline, including the spoutlike, porrect, 2-porose beak 9.5-12 mm; ovary densely fuscous-velutino-pilosulous, sometimes in addition pilose with longer pale hairs; style filiform or almost so, gently incurved 4.4-6 mm, at apex 0.2-0.3 mm diam; ovules 28-40. Pod stiffly widely ascending or declined, broadly linear straight (8-) 10- 16 x (1.2-) 1.3-1.75 cm, piano-compressed, bicarinate by the scarcely thickened sutures, cuneately contracted at base into a stipe ±3-6 mm, the stiffly papery lustrous, finely cross-venulose, nigrescent glabrate valves corrugately elevated over the seeds in low transverse ridges (not crested lengthwise), the locules 3-4 mm long but as wide as the pod itself; seeds transverse, narrowly oblong-clavi- form compressed parallel to the valves 5.1-7.6 x 1.9-2.3(-2.5) mm, the testa light brown sometimes faintly darker-mottled, often obscurely pitted, dull or moderately lustrous, crackled in age, the linear-elliptic, highly lustrous areole 3.1-5.1 x 0.4-0.7 mm; n = 14.—Collections: 145.

Distribution and Ecology - Forest margins and clearings, riverbanks, strands and shores, often in standing water, essentially a transient denizen of open places in wet macrothermic woodland, sometimes weedy but, unlike related S. alata, seldom forming extensive thickets, mostly below 400 m but ascending to 1000 m in Chiapas, 600 m in Honduras, and 1100 m along rio Cauca in Colombia, discontinuously widespread from 18°30'N in s.-e. Mexico (Veracruz, Tabasco, Yucatan, s. Oaxaca, Chiapas) through Central America in the inter-Andean valleys of Colombia as far as Valle de Cauca and along the Pacific lowlands to Gulf of Guayaquil, Ecuador; again widespread through the Orinoco and Amazon basins from Portuguesa and Barinas, Venezuela e. to Trinidad, s.-e. through the Guianas and the Amazon delta to n. Piauf, Brazil and s.-w. on the s. affluents of the Amazon to Pasco in Peru, Rondonia in Brazil, and on rio Beni s. to 15°30'S in the Yungas of La Paz, Bolivia. At higher latitudes cultivated only; commonly infested with small stinging ants.—Fl. almost throughout the year, but most freely at the end of rainy seasons.

Discussion

Senna reticulata and S. alata are strikingly similar at anthesis and as a pair are readily distinguished from other Pictae by their ample, distally accrescent, oblong-obovate leaflets and the massive cone or cylinder of petaloid, orange-yellow bracts that surmounts the several simultaneously expanded flowers. Of the two, S. reticulata is potentially the taller, more commonly arborescent and more pubescent plant, but the one differential character that is truly reliable at anthesis is the length of the petiole; in S. reticulata the first pair of leaflets is inserted upward of 3.5 cm distant from the pulvinus whereas in S. alata it is less than 3.5 cm distant, often subcontiguous to the pulvinus. In applying this criterion, care must be taken to note the true insertion of the first pair, which are readily deciduous in some specimens but leave a tell-tale scar on the leaf-stalk. The flat nigrescent pod containing seeds that are conformably flattened parallel to the valves are extremely different from the winged pod and obcompressed seeds of S. alata, so different in fact that Britton & Brown referred the species to different genera. The ingenuous opinion of the common people, who often have only one vernacular name for the two species and use them for the same medicinal purposes, appears nevertheless to acknowledge the close kinship between them expressed in multiple similarities of form, habit and properties.

Common Names

palo de jiote, varajita , mariloa , huevo de tortuga, sambran , laureho , bajagua , galbecillo, dorance , tarantan , majagua, majaguillo, mucuteno , carrion crow bush, srabitie , dartrier , Maria-mole, retama, tampush, shmashut , matapasto grande

Distribution

Veracruz Mexico North America| Tabasco Mexico North America| Yucatán Mexico North America| Oaxaca Mexico North America| Chiapas Mexico North America| Portuguesa Venezuela South America| Barinas Venezuela South America| Trinidad and Tobago South America| Piauí Brazil South America| Pasco Peru South America| Amazonas Peru South America| Rondônia Brazil South America| La Paz Bolivia South America| French Guiana South America| Guyana South America| Suriname South America| Amazonas Colombia South America| Honduras Central America|