The Tropidophiidae, common name dwarf boas or thunder snakes,
are a
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideall ...
of
nonvenomous
Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...
snakes
Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more joints ...
found from
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
and the
West Indies
The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribbean Sea that includes 13 independent island countries and 18 dependencies and other territories in three major archipelagos: the Greater ...
south to southeastern
Brazil. These are small to medium-sized
fossorial
A fossorial () animal is one adapted to digging which lives primarily, but not solely, underground. Some examples are badgers, naked mole-rats, clams, meerkats, and mole salamanders, as well as many beetles, wasps, and bees.
Prehistoric eviden ...
snakes, some with beautiful and striking color patterns. Currently, two living
genera
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomencl ...
, containing 34
species
In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...
, are recognized. Two other genera (''
Ungaliophis'' and ''
Exiliboa'') were once considered to be tropidophiids but are now known to be more closely related to
boids
Boids is an artificial life program, developed by Craig Reynolds in 1986, which simulates the flocking behaviour of birds. His paper on this topic was published in 1987 in the proceedings of the ACM SIGGRAPH conference. The name "boid" corre ...
, and are classified in the subfamily
Ungaliophiinae. There are a relatively large number of
fossil snakes that have been described as tropidophiids (because their vertebrae are easy to identify), but which of these are more closely related to ''Tropidophis'' and ''Trachyboa'' and which are more closely related to ''Ungaliophis'' and ''Exiliboa'' is unknown.
Description
This family is confined to the
neotropics
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone.
Definition
In biog ...
, mainly in
Hispaniola
Hispaniola (, also ; es, La Española; Latin and french: Hispaniola; ht, Ispayola; tnq, Ayiti or Quisqueya) is an island in the Caribbean that is part of the Greater Antilles. Hispaniola is the most populous island in the West Indies, and th ...
,
Jamaica
Jamaica (; ) is an island country situated in the Caribbean Sea. Spanning in area, it is the third-largest island of the Greater Antilles and the Caribbean (after Cuba and Hispaniola). Jamaica lies about south of Cuba, and west of Hispanio ...
, and the
Cayman Islands
The Cayman Islands () is a self-governing British Overseas Territory—the largest by population in the western Caribbean Sea. The territory comprises the three islands of Grand Cayman, Cayman Brac and Little Cayman, which are located to the s ...
, with the greatest diversity being in
Cuba, where new species are being discovered. These snakes are relatively small, averaging to about in total length (including tail).
Behavior
Most species spend their day burrowed underground or under vegetation, surfacing only at night or when it rains. Some species are
arboreal
Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. The habitats pose nu ...
and are often seen hiding in
bromeliads
The Bromeliaceae (the bromeliads) are a family of monocot flowering plants of about 80 genera and 3700 known species, native mainly to the tropical Americas, with several species found in the American subtropics and one in tropical west Africa, ...
in trees.
Color change
The dwarf boas can change color from light (when they are active at night) to dark (inactive in the day).
This color change is brought about by the movement of dark pigment granules.
Defensive behavior
When threatened, tropidophiids coil up into a tight ball. A more peculiar defensive behavior is their ability to
bleed voluntarily from the eyes, mouth, and nostrils.
Distribution and habitat
They are found from southern
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
and
Central America
Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. C ...
, south to northwestern
South America in
Colombia, (Amazonian)
Ecuador
Ecuador ( ; ; Quechua: ''Ikwayur''; Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechua: ''Ikwadur Ripuwlika''; Shuar: ''Ekua ...
, and
Peru
, image_flag = Flag of Peru.svg
, image_coat = Escudo nacional del Perú.svg
, other_symbol = Great Seal of the State
, other_symbol_type = National seal
, national_motto = "Firm and Happy f ...
, as well as in northwestern and southeastern
Brazil, and also in the
West Indies
The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribbean Sea that includes 13 independent island countries and 18 dependencies and other territories in three major archipelagos: the Greater ...
.
Fossils
Fossils of ten extinct species in five genera
from the Paleocene, Eocene, and Oligocene of Europe, Africa, & North and South America have been assigned to the Tropidophiidae, although all of them are probably actually either ungaliophiines or stem afrophidians. Two genera, ''Falseryx'' and ''Rottophis'', both from the Oligocene of western Europe, have some similarities with living tropidophiids
as well as with ungaliophiines, but for the most part their skulls are poorly preserved, leaving paleontologists to work on just their vertebrae. Paleogene erycines dominated the snake fauna of North America prior to the Miocene explosion of colubroids, but as far as we know all of these species were much more closely related to modern rosy and rubber boas than they were to tropidophiids. The only unequivocal tropidophiid fossils are from the Pleistocene of Florida
[ (in English, with an abstract in Spanish).] and the Bahamas.
Genera
T Type genus
In biological taxonomy, the type genus is the genus which defines a biological family and the root of the family name.
Zoological nomenclature
According to the International Code of Zoological Nomenclature, "The name-bearing type of a nominal ...
.
Cited references
External links
Tropidophiidae at ''Life is Short but Snakes are Long''
{{Taxonbar, from=Q1006104
Taxa named by Leo Brongersma
Snake families