|
(Last Modified On 6/6/2013)
|
|
|
|
(Last Modified On 6/6/2013)
|
|
Species
|
Conyza bonariensis (L.) Cronq.
|
|
PlaceOfPublication
|
Bull. Torrey Bot. Club 70: 632. 1943.
|
|
Synonym
|
Erigeron bonariensis L., Sp. PI. 863. 1753. TYPE: Herb. Linn. 994.11 (LINN, not seen). Conyza floribunda H.B.K., Nov. Gen. Sp. PI. 4: 69. 1820 (18.18). TYPE: Quito, Humboldt & Bonpland 3100 (P).
|
|
Description
|
Coarse erect, sparingly branched ephemeral herb to 1.5 m tall; stems reaching 5 mm thick at the base, striate, green, evenly puberulent or sometimes glabrescent. Lower (few) leaves near the base broadly spatulate and dentate; median leaves to 10 mm long becoming somewhat smaller upwards, oblanceolate, entire or sparingly toothed, the base narrowed, sometimes into a petiolelike region, thin, puberulent, the midvein prominent, the minor venation obscure above, drying fine reticulate beneath. Inflorescence a many-headed open terminal panicle, much branched with scattered lanceolate bracts ca. 10-15 mm long; pedicels slender, to 20 mm long. Heads small, disciform with many florets; involucral bracts imbricate in ca. 2 series, 4-6 mm long, herbaceous with broad hyaline apically erose margins, glabrous to pilose; receptacle flat or slightly convex, 2-2.5 mm across, muricate; outer florets numerous, white, capillary, 3-4.5 mm long, apically denticulate, usually without a distinct ligule; inner florets few, yellow, clearly differentiated about halfway up into a slender, cylindrical limb, sparingly pubescent towards the top, the lobes deltoid-acuminate, glandular papillose at the tips, the anthers ca. 0.75 mm long, basally auriculate, apically with narrow appendages, the style branches broadly flattened with deltoid appendages, conspicuously glandular- pilose dorsally. Achene compressed, the margins slightly thickened by two prominent veins, pubescent, especially towards the base; pappus of fine strigulose bristles in 1 series, ca. 1.5 mm long.
|
|
Habit
|
herb
|
|
Note
|
The species is sometimes difficult to distinguish from C. canadensis or from large specimens of C. apurensis. In C. canadensis the leaves are narrower, the heads are smaller, the involucres and other green parts are generally less pubescent or glabrous, and there are small but distinct ligules on the outer florets. Large plants of C. apurensis which lack basal leaves may be distinguished by the large inner florets and by the manifest ligules on the outer florets. Conjza bonariensis is nearly cosmopolitan in distribution, but Cuatrecasas (1969) indicates it may be a native of Argentina. In Panama it may be found in weedy areas throughout the country. Cuatrecasas distinguishes a puberulent var. leiotheca (Blake) Cuatr. with a glabrous involucre (most Panamanian plants) from the typical, densely pubescent var. bonariensis. Marshall & McClintock (1972) distinguished C. bonariensis from C. floribunda, but examination of type material revealed they are the same. They may be correct in recognizing two similar taxa in the British flora. "Tabaquillo."
|
|
Distribution
|
nearly cosmopolitan in distribution
|
|
Common
|
Tabaquillo
|
|
Specimen
|
BOCAS DEL TORO: N slope of Cerro Horqueta, 6000-7000 ft, Allen 5007 (MO). Without definite locality, Wedel 324 (MO). CANAL ZONE: Barro Colorado Island, Bailey & Bailey 363 (BH). Gaillard Hwy. near Paraiso, Croat 10138 (MO). Gaillard Hwy. near Gamboa Bridge, Croat 14899 (MO). Llanos Francia, 400 ft, Dwyer & Lallathin 8722 (MO). Ca. 1 mi S of Madden Dam, King 5238 (US). 1 mi NW of Gamboa, Lazor 2247 (MO). Ancon Hill, Standley 26315 (US). Sosa Hill, Standley 26427 (US). Frijoles, Standley 27622 (US). Rio Pedro Miguel near East Paraiso, Standley 30019 (US). Between France Field & Catival, Standley 30364 (US). Near Fort Sherman, Standley 31223 (US). Obispo, Standley 31748 (US). CHIRIQUI: Near New Switzerland, 1800-2000 m, Allen 1372 (MO). Escuela San Benito, Volcain, Croat 10417 (MO). Monte Rey above Boquete, Croat & Porter 15661 (MO); Croat 15764 (MO). NW side of Cerro Panda, Croat 15951 (MO). Between Cerro Punta and Bajo Grande, Croat & Porter 15995 (MO). Quebrada Quanabanito beyond La Repressa, 2 mi SW of Puerto Armuelles, 0-200 m, Croat 22040, 22073 (both MO). Near Las Nubes, 2.7 mi NW of Rio Chiriqui Viejo W of Cerro Punta, 2200 m, Croat 22360 (MO). First big bridge N of David on way to Boquete, ca. 800 ft, D'Arcy & D'Arcy 6289 (MO). Slope of La Popa above Boquete, 5400 ft, D'Arcy & D'Arcy 6414 (MO). Slope of Cerro Respinga above Cerro Punta, 8400 ft, D'Arcy & D'Arcy 6567 (MO). Bajo Chorro, Boquete District, Davidson 149 (MO, US). Llanos Francia, 400 ft, Dwyer & Lallathin 8722 (MO). San Bartolo Limite, 12 mi W of Puerto Armuelles, 400-500 m, Liesner 214 (MO). E of Boquete, Stern et al. 1009 (MO). Bambito, 1 mi SW of Cerro Punta, 5600 ft, Tyson 6521 (MO). COCLE1: Cerro Pilon, Lallathin (MO). DARIEN: Without definite locality, Bristan 187 (MO). Near Campamento Buena Vista, Rio Chucunaque above Rio Tuquesa, Stern et al. 874 (MO). LOS SANTOS: 5 mi S of Pocri, Croat 9730A (MO). Los Toretos, Dwyer 2436 (MO). 17.8 mi S of Macaracas, 1100 ft, Lewis et al. 1618 (MO). PANAMA&: Pan-Am. Hwy. near Jenine, Rio Caffita, Duke 3826, 3885, 3894 (all MO). 5-6 mi E of Chepo, Duke 4026 (MO). Panama Viejo, Dwyer 2890 (MO). Juan Diaz, Standley 30569 (US). Rio Tapia, Standley 28162 (US). Cerro Jefe, Tyson et al. 4311 (MO).
|
|
Tag
|
|
|
|
Project Name
|
|
Tag
|
|
|
|