Leiopelmatidae
Encyclopedia
Leiopelmatidae, or New Zealand and North American primitive frogs, is a family belonging to the suborder Archaeobatrachia
. Their relatively primitive form indicates that they have an ancient lineage. The North American frogs of the Genus Ascaphus are now united with the New Zealand frogs of the genus Leiopelma in the Leiopelmatidae family Only four Leiopelma and two Ascaphus extant species are known to belong to the family. Leiopelma are only found in New Zealand
. Ascaphus are only found in North America.
s (the tail itself is absent in adults, although it is present in the younger frogs, who need the extra skin surface until their lungs are fully developed). The family Ascaphidae (found only in North America
), of the same suborder, share these "unique" characteristics, and hence the two have often been described as related, or even part of the same family.
Late jump recovery is unique in Leiopelmatidae. When Leiopelmatid spp. jump, they land in a "belly flop" fashion repositioning their limbs for takeoff for the next jump only after hitting the ground with the ventral surface of the torso. After landing, Ascaphus skids to a halt before recovering. The appearance of early jump recovery in more advanced taxa is a key innovation
in anuran evolution.
They are unusually small frogs, only 5 centimetres (2 in) in length. Most species lay their eggs in moist ground, typically under rocks or vegetation. After hatching the tadpole
s nest in the male's back, all without the need for standing or flowing water. However, Hochstetter's frog
lays its eggs in shallow ponds and has free-living tadpoles, although they do not swim far from the place of hatching, or even feed, before metamorphosing into adult frogs. Life span
may be long (more than 30 years) for such small organisms.
remains, also from New Zealand. They became extinct during the past 1,000 years.
Much older fossils, dating back to the Jurassic
, and also considered to belong to this family, have been found in Argentina, such as Notobatrachus
.
Archaeobatrachia
Archaeobatrachia is a suborder of Anura containing various primitive frogs and toads. As the name literally suggests, these are the most primitive frogs. Many of the species show certain physiological characteristics which are not present in other frogs and toads, thus giving rise to this group...
. Their relatively primitive form indicates that they have an ancient lineage. The North American frogs of the Genus Ascaphus are now united with the New Zealand frogs of the genus Leiopelma in the Leiopelmatidae family Only four Leiopelma and two Ascaphus extant species are known to belong to the family. Leiopelma are only found in New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
. Ascaphus are only found in North America.
Overview
Their defining characteristics are their extra vertebrae (bringing the total to nine) and the remains of the tail muscleMuscle
Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
s (the tail itself is absent in adults, although it is present in the younger frogs, who need the extra skin surface until their lungs are fully developed). The family Ascaphidae (found only in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
), of the same suborder, share these "unique" characteristics, and hence the two have often been described as related, or even part of the same family.
Late jump recovery is unique in Leiopelmatidae. When Leiopelmatid spp. jump, they land in a "belly flop" fashion repositioning their limbs for takeoff for the next jump only after hitting the ground with the ventral surface of the torso. After landing, Ascaphus skids to a halt before recovering. The appearance of early jump recovery in more advanced taxa is a key innovation
Phylogenetic comparative methods
Phylogenetic comparative methods use information on the evolutionary relationships of organisms to compare species...
in anuran evolution.
They are unusually small frogs, only 5 centimetres (2 in) in length. Most species lay their eggs in moist ground, typically under rocks or vegetation. After hatching the tadpole
Tadpole
A tadpole or polliwog is the wholly aquatic larval stage in the life cycle of an amphibian, particularly that of a frog or toad.- Appellation :...
s nest in the male's back, all without the need for standing or flowing water. However, Hochstetter's frog
Hochstetter's Frog
Hochstetter's frog is a primitive frog native to New Zealand, one of only four extant species belonging to the taxonomic family Leiopelmatidae...
lays its eggs in shallow ponds and has free-living tadpoles, although they do not swim far from the place of hatching, or even feed, before metamorphosing into adult frogs. Life span
Life expectancy
Life expectancy is the expected number of years of life remaining at a given age. It is denoted by ex, which means the average number of subsequent years of life for someone now aged x, according to a particular mortality experience...
may be long (more than 30 years) for such small organisms.
Species
Family LEIOPELMATIDAE- Genus Leiopelma
- Archey's FrogArchey's FrogArchey's frog, Leiopelma archeyi, is a primitive frog native to New Zealand, one of only four extant species belonging to the taxonomic family Leiopelmatidae. It is named after Sir Gilbert Archey , the former Director of the Auckland Institute...
, Leiopelma archeyi Turbott, 1942 - Hamilton's FrogHamilton's FrogHamilton's frog is a primitive frog native to New Zealand, one of only four extant species belonging to the taxonomic family Leiopelmatidae. It is named after Harold Hamilton. The holotype is in the collection of the Museum of New Zealand Te Papa Tongarewa.-External links:* *...
, Leiopelma hamiltoni McCulloch, 1919 - Hochstetter's FrogHochstetter's FrogHochstetter's frog is a primitive frog native to New Zealand, one of only four extant species belonging to the taxonomic family Leiopelmatidae...
, Leiopelma hochstetteri FitzingerLeopold FitzingerLeopold Joseph Franz Johann Fitzinger was an Austrian zoologist.Fitzinger was born in Vienna and studied botany at the university of Vienna under Nikolaus Joseph von Jacquin...
, 1861 - Maud Island FrogMaud Island FrogThe Maud Island frog, Leiopelma pakeka, is a primitive frog native to New Zealand, one of only four extant species belonging to the taxonomic family Leiopelmatidae....
, Leiopelma pakeka Bell, Daugherty & Hay, 1998
- Archey's Frog
- Genus Ascaphus
- Tailed FrogTailed frogThe tailed frogs are two species of frogs. The species are part of the genus, Ascaphus is the only taxon in the family Ascaphidae . The "tail" in the name is actually an extension of the male cloaca. The tail is one of two distinctive anatomical features adapting the species to life in fast-flowing...
, Ascaphus truei - Rocky Mountain Tailed Frog, Ascaphus montanus
- Tailed Frog
Extinct species
Three extinct species are known by subfossilSubfossil
Subfossil refers to remains whose fossilization process is not complete, either for lack of time or because the conditions in which they were buried were not optimal for fossilization....
remains, also from New Zealand. They became extinct during the past 1,000 years.
- †Leiopelma auroraensis
- †Leiopelma markhami
- †Leiopelma waitomoensis
Much older fossils, dating back to the Jurassic
Jurassic
The Jurassic is a geologic period and system that extends from about Mya to Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...
, and also considered to belong to this family, have been found in Argentina, such as Notobatrachus
Notobatrachus
Notobatrachus is an extinct genus of frog from the middle Jurassic Cañadon Asfalto Formation of Argentina.- Sources :* Frogs: Inside Their Remarkable World by Ellin Beltz...
.
External links
- New Zealand Frog Conservation Biology - research on New Zealand frog biology