Cyclura cornuta onchiopsis
Encyclopedia
The Navassa Island iguana (Cyclura cornuta onchiopsis) was a subspecies of rhinoceros iguana
of the genus Cyclura
that was found on the Caribbean
island of Navassa. It is most likely extinct, as a wild specimen has not been observed on the island in over 50 years.
name (Cyclura
) is derived from the Ancient Greek
cyclos (κύκλος) meaning "circular" and ourá (οὐρά) meaning "tail", after the thick-ringed tail characteristic of all Cyclura. Its specific
name, cornuta, is the feminine form of the Latin
adjective cornutus, meaning "horned" and refers to the horned projections on the snouts of males of the species. The species was first described by American herpetologist
Edward Drinker Cope
in 1885.
In 1885 Cope first described the lizard as two species in the same paper: C.[yclura] onchiopsis and C.[yclura] nigerrima, due to the animal's almost black coloration. A year later he renamed it as C. onchiopsis. Herpetologists Albert Schwartz and Richard Thomas officially reclassified it as a subspecies of C. cornuta 90 years later, based on the writings of Thomas Barbour
and Robert Mertens
, yet presented numerous data relating to scale count that suggested otherwise. In 1977, Schwartz and Carey wrote “It is even conceivable that onchiopsis should be considered a species distinct from C. cornuta on the basis of this single character (distinctly smaller dorsolateral scales) (plus perhaps other modalities), but to do so would obscure its obvious affinities with the latter species.”
In 1999, Dr Robert Powell wrote that, based on these prior studies, this animal should be elevated to full species status, distinct from C. cornuta.
s varied in length from 2 to 4½ feet, with skin colors ranging from a steely gray to a dark green and even brown, and possessed a bony-plated pseudo-horn or outgrowth which resembled the horn of a rhinoceros
.
for fertilizer; the introduction of feral dogs, goats, and rats may have been to blame. Dr Robert Powell's research while at the Department of Natural Sciences, Avila College
, Kansas City, Missouri
, suggests that the iguanas disappeared before the introduction of feral species, as a result of habitat change or hunting by man. Noted herpetoculturist David Blair maintains that some of these animals may remain in captivity somewhere in the world but admits they would be very aged specimens.
Rhinoceros Iguana
The Rhinoceros Iguana is a threatened species of lizard in the family Iguanidae that is primarily found on the Caribbean island of Hispaniola, shared by the Republic of Haiti and the Dominican Republic. They vary in length from 61 to 137 cm and skin colors range from a steely gray to a dark green...
of the genus Cyclura
Cyclura
Cyclura is a genus of lizards from the family Iguanidae. Members of this genus are known as "cyclurids" or more commonly as rock iguanas and only occur on islands in the West Indies...
that was found on the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
island of Navassa. It is most likely extinct, as a wild specimen has not been observed on the island in over 50 years.
Taxonomy
The genericGenus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
name (Cyclura
Cyclura
Cyclura is a genus of lizards from the family Iguanidae. Members of this genus are known as "cyclurids" or more commonly as rock iguanas and only occur on islands in the West Indies...
) is derived from the Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
cyclos (κύκλος) meaning "circular" and ourá (οὐρά) meaning "tail", after the thick-ringed tail characteristic of all Cyclura. Its specific
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
name, cornuta, is the feminine form of the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
adjective cornutus, meaning "horned" and refers to the horned projections on the snouts of males of the species. The species was first described by American herpetologist
Herpetology
Herpetology is the branch of zoology concerned with the study of amphibians and reptiles...
Edward Drinker Cope
Edward Drinker Cope
Edward Drinker Cope was an American paleontologist and comparative anatomist, as well as a noted herpetologist and ichthyologist. Born to a wealthy Quaker family, Cope distinguished himself as a child prodigy interested in science; he published his first scientific paper at the age of nineteen...
in 1885.
In 1885 Cope first described the lizard as two species in the same paper: C.[yclura] onchiopsis and C.[yclura] nigerrima, due to the animal's almost black coloration. A year later he renamed it as C. onchiopsis. Herpetologists Albert Schwartz and Richard Thomas officially reclassified it as a subspecies of C. cornuta 90 years later, based on the writings of Thomas Barbour
Thomas Barbour
Thomas Barbour was an American herpetologist. From 1927 until 1946, he was director of the Museum of Comparative Zoology founded in 1859 by Louis Agassiz at Harvard University in Cambridge, Massachusetts....
and Robert Mertens
Robert Mertens
Robert Mertens was a German herpetologist. The Robert Mertens' day gecko is a species named after him, and he also postulated Mertensian mimicry....
, yet presented numerous data relating to scale count that suggested otherwise. In 1977, Schwartz and Carey wrote “It is even conceivable that onchiopsis should be considered a species distinct from C. cornuta on the basis of this single character (distinctly smaller dorsolateral scales) (plus perhaps other modalities), but to do so would obscure its obvious affinities with the latter species.”
In 1999, Dr Robert Powell wrote that, based on these prior studies, this animal should be elevated to full species status, distinct from C. cornuta.
Description
These lizardLizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...
s varied in length from 2 to 4½ feet, with skin colors ranging from a steely gray to a dark green and even brown, and possessed a bony-plated pseudo-horn or outgrowth which resembled the horn of a rhinoceros
Rhinoceros
Rhinoceros , also known as rhino, is a group of five extant species of odd-toed ungulates in the family Rhinocerotidae. Two of these species are native to Africa and three to southern Asia....
.
Status
Navassa Island was visited in 1966 and 1967 and no animals were present. An entomologist visited the island again in 1986 and saw no signs of any iguanas although he was not specifically looking for them. An extensive search again in 1999 failed to find any iguanas. Military occupation of the island prior to the 1960s may have been responsible for its demise, or years of mining guanoGuano
Guano is the excrement of seabirds, cave dwelling bats, and seals. Guano manure is an effective fertilizer due to its high levels of phosphorus and nitrogen and also its lack of odor. It was an important source of nitrates for gunpowder...
for fertilizer; the introduction of feral dogs, goats, and rats may have been to blame. Dr Robert Powell's research while at the Department of Natural Sciences, Avila College
Avila College
Avila College is a Roman Catholic Independent school for girls located in the Melbourne suburb of Mount Waverley. The school was established in 1965 by the Presentation Sisters who accepted an invitation from the parishes in the Waverley area to establish a Catholic Girls' College.-History:Avila...
, Kansas City, Missouri
Kansas City, Missouri
Kansas City, Missouri is the largest city in the U.S. state of Missouri and is the anchor city of the Kansas City Metropolitan Area, the second largest metropolitan area in Missouri. It encompasses in parts of Jackson, Clay, Cass, and Platte counties...
, suggests that the iguanas disappeared before the introduction of feral species, as a result of habitat change or hunting by man. Noted herpetoculturist David Blair maintains that some of these animals may remain in captivity somewhere in the world but admits they would be very aged specimens.