Howler monkeys of the genus Ateles are New World monkeys of the family Atelidae, in the subfamily Alouattinae.
Nine species and 3 subspecies are currently recognised, including the Mexican Howler which is the only  species
present in Catemaco and Los Tuxtlas. Its one of the monkey species most often seen and heard in the wild in Central
America. It takes its "mantled" name from the long guard hairs on its sides.

Three subspecies are recognized:
Ecuadorian Mantled Howler, Golden-mantled Howler and Mexican Howler.

Golden Mantled Howler (presented here because too little information is available on the Mexican Howler)
The Mantled Howler is one of the largest Central American monkeys. It is primarily black except for a fringe of gold to
buff hair on each side that gives it its common name. When the males reach maturity, the scrotum turns white. Females
are smaller than males who can reach a body length of up to 675 mm (26.6 in). The prehensile tail is up to 655 mm (25.8
in) long. Males typically weigh between 4.5 and 9.8 kg (9.9 and 22 lb).

Male Mantled Howlers also have an enlarged hyoid bone, which is a hollow bone near the vocal cords. This enlarged
bone amplifies the calls made by the male, which give the monkey its common name of "howler". The Mantled Howler is
usually indifferent to the presence of humans. However, when it is disturbed by people, it often express its irritation by
urinating or defecating on them. It can accurately hit its observers despite being high in the trees.

The brain of an adult Mantled Howler is smaller than that of several smaller monkey species.

The Mantled Howler lives in several different types of forest, including secondary forest and semi-deciduous forest but
is found in higher densities in older areas of forest and in areas containing evergreen forest. It is the one Central
American monkey whose diet is composed mostly of leaves.

The Mantled Howler lives in groups. Group size usually ranges from 10 to 20 members. Mantled Howler groups that
have been studied have occupied home ranges of between 10 and 60 hectares (25 and 150 acres). On average,
groups travel up to about 750 metres (2,460 ft) each day.

Like other species of howler monkeys, almost all Mantled Howlers have full three color vision. This is different from
other types of New World monkeys, in which most individuals have two color vision.

The Mantled Howler is diurnal and arboreal. However, the Mantled Howler is a relatively inactive monkey. It sleeps or
rests the entire night and about three quarters of the day.

The Mantled Howler uses a polygamous mating system in which one male mates with multiple females.
Females become sexually mature at 36 months, males at 42 months. The gestational period is 186 days; births can
occur at any time of year. Adult females typically give birth every 19 to 23 months.

When a male from outside the group ousts the previous alpha male, he normally kills any infants so that the mothers
come into estrus quickly and are able to mate with him. Predators such as cats, weasels, snakes and eagles also kill
infants. As a result, only about 30% of Mantled Howler infants live more than one year. If it survives infancy, the
Mantled Howler's lifespan is typically 25 years.

The Mantled Howler is regarded as "least concern" from a conservation standpoint by the IUCN.

Mexican Howler
The Mexican Howler Monkey (Alouatta palliata mexicana) is a subspecies of the Howler Monkey. Its range includes
southeastern Mexico and Guatemala. The Mexican Howler Monkey differs from the Golden-mantled Howler Monkey
primarily in aspects of skull morphology, and in some differences in pelage (fur).

In 2008, this subspecies was determined to be critically endangered.
This subspecies is listed as Critically Endangered as it is estimated that it will experience a decline exceeding 80% over
3 generations (36 years) largely due to past and ongoing rates of habitat loss (estimated at between 4.3 and 6.2% per

The Mantled Howler is protected from international trade under Appendix I of the Convention on International Trade in
Endangered Species (CITES).[31]

Personal Observations:
I have seen Howlers on Isla Agaltepec, in the forest around Playa Escondida, around Nanciyaga, and near a village in
Mecayapan.  The Tropical Flora and Fauna park stocks some and Isla Agaltepec has been converted into a research
facility for Mexican Howlers. A dying baby was turned over to
DEMATAC (on the bottom) a few years ago.

Sources: Isla Agaltepec - Archaeology and wild monkeys
Aside from humans, the macaques are the most widespread primate genus in the world, ranging from Japan to
Afghanistan and to North Africa and Gibraltar. Twenty-two macaque species are currently recognised. Several
species of macaque are used extensively in animal testing, especially the Rhesus monkey. Stump-tailed Macaque is the
species which has been imported to Catemaco.

Stump-tailed Macaque
The Stump-tailed Macaque (Macaca arctoides), also called the Bear Macaque, is a species of macaque found in
Southern Asia. It is distributed from North-Eastern India and Southern China into the North-West tip of West Malaysia on
the Malay Peninsula. It is also found in Burma, Thailand, Vietnam, and far Eastern Bangladesh.

Most information on the species comes from captive settings as there have been very few long-term studies of the
Stump-tailed Macaque in the wild.

This Old World monkey travels on all four limbs and is usually on the ground for it is not very agile in trees. It is generally
found in subtropical and tropical broad leaf evergreen forests.

The Stump-tailed Macaque has long, thick, dark brown fur covering its body, but its face and its short tail, which
measures between 32 and 69mm, are hairless. Infants are born white and darken as they mature. As they age, their
bright pink or red faces darken to brown or nearly black and lose a lot of their hair. Males are much larger than females,
measuring between 51.7-65cm long and weighing between 9.7-10.2kg, while females measure between 48.5-58.5cm
and weigh between 7.5-9.1kg.
Like some human males, stumptail macaques become partially bald as they age.

Its diet consisting mostly of fruits. It also eats many types of vegetation such as seeds, leaves and roots, but also hunts
freshwater crabs, frogs, bird eggs and insects. Like all macaques, this species has cheek pouches to store food for
short periods of time.

Nearly all (73-100%) pet and captive macaques are carriers of the herpes B virus. This virus is harmless to macaques,
but infections of humans, while rare, are potentially fatal, a risk that makes macaques unsuitable as pets.

Gestation is 168 to 183 days, and one offspring is borne every second year.

Stump-Tails are listed as Vulnerable as due to reduction in the past and projected decline by at least 30% over the
coming 30 years (three generations) due primarily to hunting and continued rates of habitat loss.
Internationally, this species is listed under Appendix II in CITES.

Sources saved documents: 5 documentos sobre los macacos de Catemaco, in Spanish
Catemaco News: In Defense of Catemaco Monkeys
Spider monkeys are in the family Atelidae, one of the four families of New World monkeys which range  from southern
Mexico to Brazil.

There are currently 29 recognized species of atelid monkey, grouped into five genera, and two subfamilies.
Spider monkeys are in the subfamily Atelinae which includes 4 genus. The genus of Spider Monkeys contains seven
species including the Geoffroy’s Spider Monkey which has at least five subspecies  including the Mexican Spider Monkey,
which is the only species present in Catemaco and Los Tuxtlas.

Geoffroy's Spider Monkey (presented here because too little information is available on the subspecies)
Geoffroy's Spider Monkey,(ateles geoffroyi), also known as Black-handed Spider Monkey, extends over much of Central
America,  the south and much of the eastern portion of Mexico.

The monkey lives in various types of forest including rain forests, semi-deciduous forests and mangrove forests. Its diet
consists primarily of ripe fruit and it requires large tracts of forest to survive. It lives in large groups of typically 20 to 42
members which split into smaller subgroups to forage  over large tracts of forest during the day.

Home ranges for groups can exceed 900 hectares (2,200 acres). Monkeys can range about 2,000 metres (6,600 ft) each
day. It is arboreal and diurnal, and mostly inhabits the upper portion of the forest. However, it comes to the ground more
frequently than other spider monkey species.

It is one of the largest New World monkeys, often weighing as much as 9 kilograms and measuring up to 63 cm. Its arms
are significantly longer than its legs. Its hands have only a vestigial thumb, but long, strong hook-like fingers. These
adaptations allow the monkey to move by swinging by its arms beneath the tree branches. The monkey has a prehensile
tail that can support the entire weight of the monkey and that is used as an extra limb. The tail is longer than the body at
between 63 and 85 cm (25 and 33 in).

Males are slightly larger than females. The clitoris of females  is large and protrudes, looking like a penis. As a result,
females are sometimes mistaken for males by human observers. Females become sexually mature at about four years;
males at about five years. They bear young every two to four years. The gestational period is about 7.5 months, after
which a single young is typically born, although twins sometimes occur.

Sounds produced by these monkeys include barks, whinnies, squeals, squeaks and screams. Barks are typically alarm
calls. Whinnies and screams can be used as distress calls, and are also made at dawn and at dusk. Each monkey makes
a unique sound, which may allow monkeys to recognize each other through vocal communication alone.

Although they do not use tools, spider monkeys, including Geoffroy's Spider Monkey, are regarded as intelligent primates.
A study performed in 2007 concluded that spider monkeys were the third most intelligent non-human primate, behind only
orang-utans and chimpanzees, and ahead of gorillas and all other monkeys. This mental capacity may be an adaptation to
spider monkeys' frugivorous diets, which require them to be able to identify and memorize many different types of foods
and their locations.

Geoffroy's Spider Monkey sometimes rubs a mixture of saliva and ground lime tree Citrus aurantifolia leaves on its fur.
This is believed to act as an insect repellent.

It is considered to be endangered by the International Union for Conservation of Nature (IUCN).

Mexican Spider Monkey
The Mexican Spider Monkey (Ateles geoffroyi vellerosus), is a subspecies of Geoffroy's Spider Monkey, native to Mexico
and Central America.

This subspecies is listed as Critically Endangered due to an estimated past and projected future population decline well
exceeding 80% over 3 generations (45 years), primarily as a result of a high rate of habitat loss.

The Mexican Spider Monkey is protected from international trade under Appendix I of the Convention on International Trade
in Endangered Species (CITES).[31]

Personal Observations:
I have never seen a wild Spider Monkey in Los Tuxtlas, but I have been offered a baby for sale. Supposedy there is a
troop on Volcano San Martin. I don't believe it. There are confirmed isolated troops in the Sierra Santa Marta.

Sources:'s_Spider_Monkey Tropical Fauna & Flora Park, a research facility for Spiders in Catemaco
Four primate species are present in Catemaco and Los Tuxtlas.

Primates are mammals who showed up on the evolutionary scale about 220 million years ago.According
to fossil evidence, the primitive ancestors of primates may have existed in the late Cretaceous period
around 65 million years ago.

The Primates order has traditionally been divided into two main groupings: prosimians and simians.
Simians included the monkeys and apes, including humans.

Simians are divided into three groups: the platyrrhines ("flat nosed") or New World monkeys of South
and Central America, the catarrhine (narrow nosed) or Old World monkeys of Africa and southeastern
Asia, and the strepsirrhini, or curly-nosed primates mostly living on Madagascar.

Two of the groups, including 4 species, are present in Catemaco and Los Tuxtlas.
Of the New World monkeys, there are two species: Mexican Spider Monkey and  Mexican Howler
Of the Old World monkeys, 2 species are present: Stump tailed Macaques and Humans (Homo Sapiens),

New World Mexican Spider and Howler monkeys are almost extinct, are on the endangered species list
and only survive in limited forest patches and government observation facilities.

Old World Stump tailed Macaques and Humans are recent arrivals to Los Tuxtlas.
Modern-appearing humans originated in Africa about 200,000 years ago, reaching full behavioral modernity
around 50,000 years ago. The first human presence in the Americas is from around 30,000 BC, while first
documented presence in Mexico dates from about 10,000 BC.

Pollen studies indicate the presence of humans in Los Tuxtlas since before 3000 BC.

Humans are the only primates with a significant presence in Los Tuxtlas, numbering app. 400,000. They are
considered a predatory species and have successfully eliminated most competitors for food sources in the local

Although economic slavery, sale of children and women is still known in Los Tuxtlas,  the Convention on
International Trade in Endangered Species does not include humans.

Apparently ignoring the population explosion and consequent destruction of the global environment which
foreseeably may exterminate the human race, the  International Union for Conservation of Nature (IUCN), does
not list the species in its Red Book.
Howler Monkeys
Spider Monkeys
The observations below are primarily assembled from Wikipedia and a few other sources
Descendants of possibly the first humans in Los Tuxtlas
Veracruz, Mexico
The Primates of Catemaco