Tukeit Hill Frog
Encyclopedia
The Tukeit Hill Frog is the only described species
in the genus
Allophryne and the only member of the subfamily
Allophryninae, a clade recently placed under the family Centrolenidae. These frogs live in Guyana
, Venezuela
, Surinam, Brazil
and Bolivia
. The holotype
was discovered at Tukeit Hill, below Kaieteur Falls
, Guyana, hence the common English
name.
s, however the end of their phalanges differ in shape (see below Taxonomic classification).
subfamily
of anurans: Allophryninae. The evolutionary relationships of this species
have always been controversial. It has been joint to families like Hylidae, Bufonidae, and Leptodactylidae, but until recently its closer relatives where unknown.
Allophryne is similar in its general shape to tree frog
s of the family Hylidae, but Allophryne differs by having the last phalanges of fingers and toes T-shaped, a character found in Glassfrogs while Tree frog
s have them claws-shaped. When the herpetologist G. K. Noble
examined Allophryne, he suggested that it was closely related to Glassfrogs, a hypothesis later confirmed by recent phylogenetic studies that have found that Allophryne is the sister taxon
of the glassfrog clade Centroleninae
(Austin et al. 2002, Frost et al. 2006).
The Glassfrogs differ from Allophryne by having much more delicate skulls and by possessing intercalary elements between the last phalanges of fingers, a process on the third metacarpal, and non-explosive breeding, among other characteristics. Both Glassfrogs and the Allophrynidae are closely related to Leptodactylidae
.
Recently, an undescribed species of frog which probably belongs to the genus Allophryne was discovered in Peru
http://fm2.fieldmuseum.org/rbi/gallery_peru11/3.asp. This suggests that the genus is actually more widespread and that more species await discovery. As A. ruthveni was assumed to be a northwest Amazonian endemic, the Peruvian frog indicates that the Allophrynidae might have been more widespread in prehistoric times, only later on disappearing from most of the Amazonas basin, and are actually a relict
group. Alternatively, they might occur in the western Amazonas lowlands and simply have not been found yet, though this seems less likely.
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
in the genus
Genus
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...
Allophryne and the only member of the subfamily
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Allophryninae, a clade recently placed under the family Centrolenidae. These frogs live in Guyana
Guyana
Guyana , officially the Co-operative Republic of Guyana, previously the colony of British Guiana, is a sovereign state on the northern coast of South America that is culturally part of the Anglophone Caribbean. Guyana was a former colony of the Dutch and of the British...
, Venezuela
Venezuela
Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...
, Surinam, Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
and Bolivia
Bolivia
Bolivia officially known as Plurinational State of Bolivia , is a landlocked country in central South America. It is the poorest country in South America...
. The holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
was discovered at Tukeit Hill, below Kaieteur Falls
Kaieteur Falls
Kaieteur Falls is a high-volume waterfall on the Potaro River in central Guyana, Potaro-Siparuni region. It is located inKaieteur National Park. It is 226 meters high when measured from its plunge over a sandstone and conglomerate cliff to the first break...
, Guyana, hence the common English
English language
English is a West Germanic language that arose in the Anglo-Saxon kingdoms of England and spread into what was to become south-east Scotland under the influence of the Anglian medieval kingdom of Northumbria...
name.
Description
The Tukeit Hill Frog is a small frog. It is of variable colouration, either black, with stripes and spots which can be golden or dull yellow, or a dull yellow or golden ventral surface, with black strips and spots. It has a flat body, and small flat head. It has a single, sub-mandibular vocal sac. The toe pads are enlarged, wider than the fingers, and the tympanum is visible. The Tukeit Hill Frog is superficially similar to the tree frogTree frog
Hylidae is a wide-ranging family of frogs commonly referred to as "tree frogs and their allies". However, the hylids include a diversity of frog species, many of which do not live in trees, but are terrestrial or semi-aquatic.-Characteristics:...
s, however the end of their phalanges differ in shape (see below Taxonomic classification).
Taxonomy
Allophryne, the Tukeit Hill Frog, is part of a hitherto (see below) monotypicMonotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
subfamily
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
of anurans: Allophryninae. The evolutionary relationships of this species
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...
have always been controversial. It has been joint to families like Hylidae, Bufonidae, and Leptodactylidae, but until recently its closer relatives where unknown.
Allophryne is similar in its general shape to tree frog
Tree frog
Hylidae is a wide-ranging family of frogs commonly referred to as "tree frogs and their allies". However, the hylids include a diversity of frog species, many of which do not live in trees, but are terrestrial or semi-aquatic.-Characteristics:...
s of the family Hylidae, but Allophryne differs by having the last phalanges of fingers and toes T-shaped, a character found in Glassfrogs while Tree frog
Tree frog
Hylidae is a wide-ranging family of frogs commonly referred to as "tree frogs and their allies". However, the hylids include a diversity of frog species, many of which do not live in trees, but are terrestrial or semi-aquatic.-Characteristics:...
s have them claws-shaped. When the herpetologist G. K. Noble
Gladwyn Kingsley Noble
Gladwyn Kingsley Noble was an American zoologist.- Works :*"American Egret at Martha's Vineyard, Mass" The Auk Vol. 31 N. 1: 100...
examined Allophryne, he suggested that it was closely related to Glassfrogs, a hypothesis later confirmed by recent phylogenetic studies that have found that Allophryne is the sister taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
of the glassfrog clade Centroleninae
Centroleninae
Centroleninae is one of three subfamilies of the family. It has nine genera.-Genera:*Centrolene *Chimerella*Cochranella *Espadaranaa*Nymphargus *Rulyrana*Sachatamia*Teratohyla...
(Austin et al. 2002, Frost et al. 2006).
The Glassfrogs differ from Allophryne by having much more delicate skulls and by possessing intercalary elements between the last phalanges of fingers, a process on the third metacarpal, and non-explosive breeding, among other characteristics. Both Glassfrogs and the Allophrynidae are closely related to Leptodactylidae
Leptodactylidae
Leptodactylidae is a diverse family of frogs that probably diverged from other hyloids during the Cenozoic era, or possibly at the end of the Mesozoic. There are roughly 50 genera, one of which is Eleutherodactylus, the largest vertebrate genus, with over 700 species...
.
Recently, an undescribed species of frog which probably belongs to the genus Allophryne was discovered in Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....
http://fm2.fieldmuseum.org/rbi/gallery_peru11/3.asp. This suggests that the genus is actually more widespread and that more species await discovery. As A. ruthveni was assumed to be a northwest Amazonian endemic, the Peruvian frog indicates that the Allophrynidae might have been more widespread in prehistoric times, only later on disappearing from most of the Amazonas basin, and are actually a relict
Relict
A relict is a surviving remnant of a natural phenomenon.* In biology a relict is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas....
group. Alternatively, they might occur in the western Amazonas lowlands and simply have not been found yet, though this seems less likely.