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Pigs, Peccaries and
Hippos Status Survey and Action Plan (1993) Chapter 2 THE NEOTROPICAL PECCARIES - DICOTYLIDAE Tayassu and Catagonus 2.1 Taxonomy and Description Peter Grubb and Colin P. Groves Introduction There are two genera and three
extant species of peccaries. These are the collared peccary, Tayassu tajacu, the white-lipped
peccary, Tayassu pecari (= albirostris),
and the giant or Chacoan peccary, Catagonus
wagneri. The peccaries, both living and extinct, are assigned to a separate
family within the Suiformes, the Dicotylidae. The name Tayassuidae has also
been widely used to denote this Family, but this is not correct as it dates
from Palmer, 1897, while Dicotylidae dates from Turner, 1849. Being an older
name, the latter takes precedence according to the International Code of
Zoological Nomenclature (International Commission of Zoological Nomenclature,
1985), as clearly shown by Husson (1978). There are also some problems with
the generic name Tayassu,
particularly if the two living species should no longer be regarded as
congeneric, as Woodburne (1968) has suggested. Unfortunately, both of these
species have at one time or another been assigned to a separate genus Dicotyles. In fact, Dicotyles and Tayassu were coined independently for the two species, and
neither is unequivocally associated with one species or the other by the
authors of the names. However, whilst such problems are relevant to our
understanding of peccary phylogeny, they are of limited significance to conservation
and, for the purposes of this Action Plan, the single genus Tayassu is retained for both species. The three extant species, and some
other problems with their existing subspecific nomenclature, may be described
as follows: The Collared Peccary (Tayassu
tajacu) This species, the smallest and
most widely distributed of the living peccaries, occurs from southern Texas,
New Mexico and Arizona in the United States, south through northwestern
Sonora in Mexico to Tubes and Piura in Peru, west of the Andes, and Santiago
del Estero in Argentina, east of the Andes. The species is extremely
eurytopic, inhabiting deserts, arid woodlands, oak woodlands and tropical
rain forests. It is a comparatively small animal, perhaps reaching as much as
30 kg but averaging 22 kg for males from the Chaco, with females a little
less. In proportions it is large-headed with relatively slight, slender
limbs. Body measurements (total length and lengths of tail, hind-foot and
ear, in mm) have been given as 870-940, 19-55, 180-200, 84-100 (Hall &
Kelson, 1959), source not stated but presumably applying to North American
populations. Mayer & Brandt (1983) gave rather higher figures for Chaco
specimens: males 840-1,040, 10-106, 163-253, 27-98; females 788-1,060, 10-60,
170-235, 27-93. The general color of the pelage is a strongly speckled dark
blackish gray, blacker on the limbs and along the dorsal crest, with a
whitish band passing across the chest from shoulder to shoulder. The juvenile
coat is grizzled reddish-tan with a distinct dark brown mid-dorsal stripe and
light shoulder collar. Change to the adult coloration occurs at two to three
months of age. The diploid chromosome number is 30. There has been no modern revision
of the species. Two species or subspecies-groups have been differentiated in
the past, the 'angulatus' group in
Central America and the nominate 'tajacu'
group in South America. This situation could parallel the biogeography of
other Neotropical mammals, such as tapirs, tamanduas or coatis, but it is not
currently recognized and needs further investigation. Woodburne (1968)
concluded that geographic variation in this species was relatively gradual,
that characters distinguishing the angulatus
group were not confined to Central America and that only one species should
be recognized. The fourteen described subspecies may be divided informally
into three groups, as follows: 1) South American gray to buff subspecies with
clearly marked pale collar and black dorsal stripe: tajacu Linnaeus, 1758, Brazil. 2) Blackish forms with very poorly expressed collar
and dorsal stripe: patira Kerr,
1792, French Guiana (synonym: macrocephalus
Anthony, 1921, Guyana); torvus
Bangs, 1898, Colombia; crusnigrum
Bangs, 1902, Panama; niger Allen,
1913, Ecuador; bangsi Goldman,
1917, Panama (synonym: modestus
Cabrera, 1917, Colombia). Hershkovitz (1963) doubts whether most of these can
be distinguished from patira. 3) Grey Central American forms: angulatus Cope, 1889, Texas; sonoriensis
Mearns, Sonora, Mexico; nanus, humeralis, yucatanensis and crassus,
all of Merriam, 1901, from Cozumel I., Colima, Yucatan and Puebla
respectively, all in Mexico; nelsoni
and nigrescens of Goldman, 1926,
from Chiapas, Mexico, and Honduras, respectively (nigrescens perhaps representing intergradation with patira - sensu lato). The White-Lipped Peccary (Tayassu
pecari) This species has a less extensive
distribution than the collared peccary, occurring from Veracruz and Oaxaca in
southern Mexico, south to Esmeraldas and Pichincha in Ecuador west of the
Andes, and Entre Rios in Argentina east of the Andes. Most of its range is
within tropical rain forest, but it also occurs in drier habitats such as the
savannas of Venezuela and the Gran Chaco of Paraguay. It is larger that T. tajacu. Recorded body weights range
from 25 to 40 kg, averaging 28kg, and a pregnant female from the Chaco
weighed 38kg (Mayer & Brandt, 1982; Mayer & Wetzel, 1987). Body
measurements in mm, again from Chaco specimens, for males are: 961-1,390,
10-55, 165-233 and 73-85; and for females: 905-1,250, 20-65, 181-250, 68-80
(Mayer & Brandt, 1982). In color the white-lipped peccary is blackish
brown becoming grizzled or light-colored in the pectoral and inguinal
regions. The face and mid-dorsum are often grizzled black and tan, as are the
legs, with white adjacent to the hooves and on the lateral and hind surfaces
of the forelimbs. In contrast to the body color, the chin, cheeks and sides
of the muzzle are white or yellowish-white. The ears are black with white
insides. The juvenile pelage is mixed red-brown, black and cream with a black
mid-dorsal stripe and white undersides, legs and rostrum. The coat darkens
during the first year and changes to the adult coloration in the second, so
that maturation of the pelage takes much longer than in the other peccaries.
Specimens without the white cheeks are known (W. Oliver pers. comm.) and they
may represent an undescribed subspecies if they are not merely subadults that
have yet to acquire the full adult pelage. The diploid chromosome number is
26. There has been no modern revision
of the species. However, since the type locality of Tayassu pecari (Link, 1795), is Cayenne, French Guiana
(Hershkovitz, 1963, followed by Mayer & Wetzel, 1987), and not Paraguay
as widely stated, the nominate subspecies T.
p. pecari cannot have a distribution excluding the Guianas (Mayer &
Wetzel, loc. cit.). The prior name for the animals in Brazil and further
south is T. p. albirostris
(Illiger, 1815) (type locality, Paraguay). The prior name for animals north of
Brazil is T. p. pecari of which beebei (Anthony, 1921) must surely be
a synonym. The five generally recognized subspecies should therefore be named
as follows: 1) T. p. pecari Link, 1795, French Guiana (synonym: beebei Anthony, 1981, Guyana),
Guianas. 2) T. p. albirostris Illiger, 1815, Paraguay. 3) T. p. ringens Merriam, 1901, Campeche, Mexico. 4) T. p. spiradens Goldman, 1912, Costa Rica. 5) T. p. equatoris Lönnberg, 1921, Ecuador. In line with Hershkovitz (1963),
who treats the species as monotypic, the status of all these subspecies
should be regarded as doubtful and requiring review, though it is possible
that the Central and South American populations should be distinguished
subspecifically. The Chacoan Peccary (Catagonus
wagneri) Not recognized as an extant form
until 1974, this species is known only from the dry thorn forest in the Gran
Chaco of northern Argentina, southeastern Bolivia and western Paraguay
(Wetzel, 1977a,b). It is the largest and most distinct of the living species.
It may be distinguished from the other peccaries by its much larger head,
longer ears with long whitish hairs, and paler hair on the legs and feet
rather than dark hair. The skull length is nearly one third (28%) of total
length, compared with one quarter for the white-lipped peccary. The Chacoan
peccary is a brownish-gray animal with a collar of whitish bristles around
the shoulders, similar to the collar of the considerably smaller collared
peccary. The bristles are much paler on the basal half than the vivid black
and white banded hairs of the latter, and differ in detailed structure from
those of both Tayassu species.
Newborn juveniles have a mixture of mostly tan and black bristles in the
coat, with a black mid-dorsal stripe and a tan collar across the shoulder,
the pattern less distinct than in collared peccaries of similar age. The end
of the snout, the digits and the anterior edges of the forelimbs are brown to
black. Unlike those of adults, the bristles are entirely black, brown, tan or
white, and they are longer than those of juvenile Tayassu species. Change to adult coloration occurs at three to
four months of age. Body measurements in mm from Mayer & Brandt (1982)
for males are 957-1,161; 24-102; 206-250; 100-122; and for females
1,030-1,170, 170; 45-100; 222-257; 100-120. Body weight is 29.5-40 kg in
males, 30.5-38.5 kg in females, but up to 43.5 if pregnant. The Chacoan peccary is the most
specialized of the living peccaries in that it lacks dewclaws on the hind
feet, present (second digit) in the other peccaries. It also has cranial and
dental specializations suggesting adaptation to dry, relatively open
environments. The teeth are high-crowned, there is a distinct basicranial
flexure, the orbits are set well back and the nasal cavity and cranial
sinuses are enlarged. These features are adaptations associated with browsing
and scanning the surroundings during mainly diurnal activities, in a
situation where the air may be charged with dust. The diploid number of chromosomes
in the species is 20. A full reconstruction of karyotypic evolution among
peccaries cannot yet be made, but C.
wagneri seems to be the most distinct of the three living species in the
number and structure of its chromosomes (Benirschke et al., 1985). References Benirschke, K., Kumamoto, A. T. and Merrit, D. A. 1985. Chromosomes of
the Chacoan peccary, Catagonus wagneri
(Rusconi). J. Heredity, 76: 95-98. Hall, E. R. and Kelson, K. R. 1959. The mammals of North America, Vol.
2. Roland Press, New York. Hershkovitz, P. 1963. The nomenclature of South American peccaries.
Proc. Biol. Soc. Washington, 76: 85-88. Husson, A. M. 1978. The Mammals of Suriname. E. J. Brill, Leiden. Mayer, J. J. and Brandt, P. N. 1982. Identity, distribution, and
natural history of the peccaries, Tayassuidae. In: M. A. Mares & H. H.
Genoways (eds.), Mammalian Biology in South America, Spec. Publ. Series,
Pymatuning Laboratory of Ecology, Univ. of Pittsburg: 433-455. Mayer, J. J. and Wetzel, R. M. 1987. Tayassu pecari. Mammalian Species 293: 1-7. International Commission on Zoological Nomenclature 1985.
International Code of Zoological Nomenclature. 3rd ed., International Trust
for Zoological Nomenclature, London. Wetzel, R. M. 1977a. The extinction of peccaries and a new case of
survival. Ann. New York Acad. Sci. 288: 538-544. Wetzel, R. M. 1977b. The Chacoan Peccary Catagonus wagneri (Rusconi). Bull. Carnegie Mus. Nat. Hist. 3:
1-36. Woodburne, M. O. 1968. The cranial myology and osteology of Dicotyles tajacu, the collared
peccary, and its bearing on classification. Mem. Sthn. Calif. Acad. Sci. 7:
1-48. |
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Next: Chapter 2.2 – The Collared
Peccary |