Tailed frogs and New Zealand frogs
Tailed frogs and New Zealand frogs are fascinating amphibians belonging to the ancient family Leiopelmatidae, notable for their primitive characteristics. They lack eardrums and vocal sacs, and exhibit a small tail structure, with tailed frogs possessing a complete tail and New Zealand frogs having only muscle groupings. Tailed frogs, which include the coastal and Rocky Mountain species, inhabit fast-flowing streams in western North America, while New Zealand frogs, comprising three species, are found in the damp soils of New Zealand's mountains.
Both types of frogs are carnivorous, feeding primarily on aquatic insects and small invertebrates. Their reproductive behaviors differ; tailed frogs mate underwater without vocal calls, while New Zealand frogs lay their eggs in crevices and often exhibit parental care. Tailed frog tadpoles are equipped with suckers for adhering to surfaces, and their development can take several years before reaching maturity. Both species can live up to 14 years, making them remarkable examples of ancient amphibian lineage.
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Tailed frogs and New Zealand frogs
Tailed frogs and New Zealand frogs are members of the oldest surviving family of frogs. They are distinct in three major primitive features. They do not have eardrums. They do not have vocal sacs. And finally, they have the muscle structure or bone structure for a small tail. This tail is complete in the tailed frogs and only a muscle grouping in the New Zealand frogs.
Kingdom: Animalia
Phylum: Chordata
Class: Amphibia
Order: Anura
Family: Leiopelmatidae
Genus: Various (see below)
Species: Various (see below)
The two species of tailed frogs belong to the genus Ascaphus—the coastal-tailed frog (Ascaphus truei) and the Rocky Mountain-tailed frog (Ascaphus montanus). The genus Leiopelma contains the three New Zealand frogs—Archey's frog (Leiopelma archeyi), Hamilton's frog (Leiopelma hamiltoni), and Hochstetter's frog (Leiopelma hochstetteri).
Although tailed and New Zealand frogs differ in location and environment, they share similar, primitive features. Neither tailed nor New Zealand frogs have eardrums or vocal sacs, but both have at least the muscle groupings to control a small tail. Only males have these "tails," which are part of the cloaca used during mating. These three features are unique among frogs, setting these species apart as members of a much older family.
Tailed and New Zealand frogs have gray, brown, black, or pinkish skin. They grow to one to two inches (two and five centimeters) long. These tiny frogs have slender bodies, with broad, flat heads. Like other frogs, their hind legs are much longer than their front legs. This construction aids the frogs in leaping and jumping from place to place. At the ends of their legs, tailed frogs and New Zealand frogs have long, slender toes which are slightly webbed to help them swim. Like other amphibians, tailed frogs and New Zealand frogs are cold-blooded. This means their body temperatures are the same as the temperature of their surroundings.
Tailed frogs live in the fast-flowing mountain streams of western North America. New Zealand frogs live on the damp soil of mountainsides in New Zealand. New Zealand frogs are the only frogs native to New Zealand.
Both species are carnivorous, or meat-eating frogs. They live on a diet of aquatic, or water-living, insects and other tiny invertebrates, or spineless creatures. Shrews, snakes, salamanders, fish, and birds prey on these frogs.
Tailed frogs mate in September and October. Since they do not have vocal sacs, tailed frogs swim along the bottom of the stream to find their mates. After mating in the water, the females lay 45 to 85 eggs in June or July. The eggs hatch after six weeks. Tailed frog tadpoles have large suckers on their mouths to help them stick to a stone while they are feeding. Coastal species spend one to three years as larvae, and mountain species spend three to four years in metamorphosis. The young reach maturity after two to nine years. Female New Zealand frogs lay clutches, or batches, of 1 to 22 eggs in damp crevices in rocks and logs. The males care for the eggs during their incubation period, or from when they are laid until they hatch. Some species of New Zealand frogs may carry the young on their backs during incubation, a practice common in many frogs and toads.
Tailed frogs and New Zealand frogs may live up to 14 years.
Bibliography
"Frogs/Pepeketua." New Zealand Department of Conservation, www.doc.govt.nz/nature/native-animals/reptiles-and-frogs/frogs-pepeketua. Accessed 15 May 2024.
"Leiopelmatidae - New Zealand and North American Primitive Frogs." PBS, nhpbs.org/wild/Leiopelmatidae.asp. Accessed 15 May 2024.
Potter, Ashley. "Ascaphus Truei." Animal Diversity Web, animaldiversity.org/accounts/Ascaphus‗truei. Accessed 15 May 2024.