Vachellia collinsii

Vachellia collinsii

Vachellia collinsii

Vachellia collinsii

Vachellia collinsii

Vachellia collinsii

Vachellia collinsii


Vachellia collinsii  (Safford) Seigler & Ebinger, Phytologia 87:150. 2005.
syn. Acacia collinsii Safford, Science N.S. 31:677. 1950

Synonymy and types

Basionym:  Acacia collinsii Saff., Science N.S.  31: 677.  1910.  Myrmecodendron collinsii (Saff.) Britton & Rose, N. Amer. Fl.  23:  92.  1928. - TYPE:  MEXICO.  CHIAPAS:  between Chicoasén and San Fernandino, 1,005 ft., 13 Jan 1907, G. N. Collins & C. B. Doyle 180 (holotype:  US, F photo).  NOTE:  Safford (1910) listed G. N. Collins as the only collector, and cited 14 Jan. 1907 as the date collected.  On the label of the type specimen G. N. Collins and C. B. Doyle are listed as the collectors and 13 Jan. 1907 is given as the date of the collection.

Acacia glutea Ram. Goyena, Fl. Nicaragüense  1:  382.  1909. - TYPE:  not cited.  NOTE:  Although the original description of Ramírez Goyena is in Spanish and no type is cited (Rico Arce, 2001), this species was described before either of these was required.  Because this name is not accepted by most workers, is not supported by type material, nor is a designated herbarium extant, in order to contribute to nomenclatural stability, we have made a proposal to conserve the name of Safford (1910), which is widely used.  If accepted, the name for this taxon must become Vachellia collinsii (Saff.) Seigler & Ebinger.

Acacia costaricensis Schenck, Repert. Spec. Nov. Regni Veg.  12: 361.  1913.  Myrmecodendron costaricensis (Schenck) Britton & Rose,  N. Amer. Fl.  23: 93.  1928. -  TYPE:  COSTA RICA.  ALAJUELA:  Alajuela, alt. 900 m, 1896, J. D. Smith 6488  [lectotype, designated by Seigler and Ebinger (1995):  S (B, destroyed); isotypes: BM, GH, K, MO].

Acacia panamensis Schenck, Repert. Spec. Nov. Regni Veg. 12: 362.  1913. - TYPE:  PANAMA.  ALAJUELA:  A. Koch s.n. (holotype:  B, destroyed).

Acacia yucatanensis Schenck, Repert. Spec. Nov. Regni Veg.  12: 361.  1913. - TYPE:  MEXICO.  YUCATÁN, 1895, G. F. Gaumer 353 [lectotype, designated by Seigler and Ebinger (1995):  US (B, destroyed); isotypes:  BM, GH, F, MO].

Acacia nelsonii Saff., J. Wash. Acad. Sci.  4: 363.  1914. - TYPE:  MEXICO.  GUERRERO:  Acapulco, sea level, 30 Apr 1903, E. W. Nelson 7024 (holotype:  US; isotypes:  GH, F).

Acacia penonomensis Saff., J. Wash. Acad. Sci.  4: 363.  1914. - TYPE:  PANAMA.  COCLÉ:  Penonomé, 50-1,000 ft., 23 Feb-22 Mar 1908, R. S. Williams 113 (holotype:  NY, F photo, US fragment and photo; isotype:  US).

Formal description

Tree to 10 m tall.  Bark dark gray to brown, shallowly furrowed.  Twigs reddish brown to dark brown, not flexuous, glabrous.  Short shoots absent.  Leaves alternate, 40-195 mm long.  Stipular spines light reddish brown to dark brown, rarely ivory to yellowish, mostly symmetrical, terete, straight, stout and inflated, 20-50 x 13 mm near the base, glabrousPetiole adaxially grooved, 4-18 mm long, glabrous to lightly puberulent; petiolar glands (2)3 to 5, usually near the base of the petiole, sessile, dome-shaped to broadly volcano-shaped, base 1.0-2.5 mm across, apex nearly circular, 0.3-0.8 mm across, puberulent.  Rachis adaxially grooved, 30-180 mm long, glabrous to lightly puberulent, rachis glands mostly absent.  Pinnae 3 to 15 pairs per leaf, 30-90 mm long, 7-17 mm between pinna pairs.  Petiolules 0.7-1.5 mm long.  Leaflets 11 to 29 pairs per pinna, opposite, 1.0-2.5 mm between leaflets, oblong, 6-13 x 1.3-3.1 mm, glabrous, lateral veins obvious, 2 to 3 veins from the base, base oblique, margins usually not ciliate, apex obtuse; beltian bodies 0.4-0.8 mm long.  Inflorescence a densely flowered cylindrical spike nearly the same thickness throughout, 15-35 x 4-6 mm, commonly in short, leafy racemose clusters to 80 mm long with 1-3(5) spikes per node.  Peduncles 6-20 x 0.8-1.8 mm, glabrous to lightly puberulent.  Involucre 4-lobed, located near the base to lower third of the peduncle, glabrous to lightly puberulent, persistent.  Floral bracts peltate, 0.6-1.1 mm long, apex circular and usually puberulent, deciduous.  Flowers sessile, yellowish; calyx 5-lobed, 1.0-1.4 mm long, glabrous; corolla 5-lobed, 1.1-1.5 mm long, slightly longer than the calyx, glabrous; stamen filaments 1.5-2.5 mm long, distinct; ovary glabrous, subsessile.  Legumes dark brown to black, nearly straight, elliptical in cross section, not constricted between the seeds, oblong, 30-60 x 7-13 mm, coriaceous, not striate, glabrous, eglandular, dehiscent along both sutures; stipe absent; apex acute, short beaked to 1-6 mm long.  Seeds uniseriate, imbedded in a yellow aril, dark brown, ovoid, slightly flattened, 5.3-7.9 x 3.5-5.5 mm, smooth; pleurogram oval, 3-4.5 mm across. Flowers in January to August. Chromosome number: Not determined.


Shrubby vegetation of pastures, successional fields, edge of roads, scrub forest, and rocky ridges in habitats ranging from wet to moderately dry in the lowlands from along the west coast of Mexico from Guerrero east to the Yucatán Peninsula, south through Central America to Colombia (Seigler and Ebinger 1995).

Additional info

Vachellia collinsii has the most extensive geographical distribution of all New World ant-acacias, and is the only ant-acacia known to occur in South America.  This species also has the widest ecological distribution, growing in dry to moderately wet pastures and fields and in open shrubby vegetation from sea level to 1,000 m.  It is a common component of early successional areas, being particularly abundant in habitats too dry for the other ant-acacias (Janzen 1974).  This wide ecological and geographical distribution has resulted in a relatively broad morphological diversity, which is reflected in the extensive synonomy.  Though morphologically diverse, Acacia collinsii can easily be distinguished from all other ant-acacias by the following combination of characters:  elongated cylindrical inflorescences, 3-5 petiolar glands that are broadly dome-shaped, absence of rachis glands, and leaflets with obvious lateral veins.  Also, most individuals have relatively small stipular spines that are terete in cross section; occasional individuals are encountered with stipular spines that have the base enlarged and flattened, a characteristic of A. hindsii.

As is typical of most xerophytic ant-acacias, Beltian body production in Vachellia collinsii is relatively high.  In this species, the nearly globose Beltian bodies usually are found on more than 50% of the leaflets of developing leaves.  As most individuals of this species are inhabited by obligate acacia-ants, the Beltian bodies are generally "harvested" soon after development.

Cyanide tests of more than 400 specimens of Vachellia collinsii indicate that this species is not cyanogenic.  Herbarium material of this species was reported cyanogenic (Seigler et al. 1978), but reinvestigation of these same specimens failed to confirm activity (Seigler and Ebinger 1987). Janzen (1981) did not report cyanogenesis for this species.

Vachellia collinsii probably hybridizes with V. hindsii.  These species are sympatric in parts of their ranges in Mexico and Central America, and occasionally occur at the same site.  Vachellia collinsii also hybridizes with the non-ant-acacia V. pennatula (Ebinger & Seigler 1992).

Flowering time


Representative specimens










San José:


La Unión:


El Petén:













Quintana Roo:














Canal Zone:




Los Santos:





Dade Co.: