Flashcards
Amphibians
Flashcards do conjunto (8)
- 1Amphibian characteristicsCarnivorous/Insectivorous
Papilla Amphibiorum
Loss of posterior skull bones
Amphibian skin
Ectothermic
Triploblasts
Bilateral symmetry - 2Amphibian skin:• Glandular and permeable • Respiratory gas exchange
- 3Amphibian classification:3 orders of Amphibia: • Anura (frogs and toads) • Caudata (Salamanders and newts) • Gymnophiona (Caecilians
- 4Anura• Anura = ‘without tail’ • Frogs and Toads • Rule of thumb: smooth skin = frog, warty skin = toad • Toads are a sub-group of frogs (Bufonidae) • All toads are frogs, but not all frogs are toads • 45 families, ~5400 species • Most numerous group of amphibians • Found on all continents except Antarctica
- 5Anura locomotion:• Unique to frogs and toads • Large hindlimbs, short forelimbs
- 6Caudata characteristics:• Caudata = ‘tail’ • Salamanders and Newts • 9 families, ~655 species • Lizard-like body morphology • Lateral undulation • Internal fertilisation • Metamorphosis • Extant forms often grouped as ‘Urodela’
- 7Gymnophiona (Caecilians)• ‘Caecus’ = blind • 10 families, <200 species (see Wilkinson et al 2011. Zootaxa2874:41-64) • Live in the tropics • Limbless • Burrowing or aquatic • Large forms upto 1.5 m in length • Superficially similar to worms or snakes. • Skin surrounded by ringshaped folds, making them look segmented
Blind (or nearly blind) • Diet not well known: • Hebrard et al 1992, (J. of Herpetology) found gut contents consisting mainly of unidentifiable organic matter • Reproduction – Internal insemination • Male has a ‘phallodeum’ • ~25% of speicies are oviparous, rest are vivaparous - 8Amphibian decline:Amphibian decline
• Amphibians face serious declines, particularly since the 1980’s (most post-1500 extinctions occurred since 1980) • Current extinction rate may be 211 times background rate for amphibians* • IF species in ‘imminent danger’ are counted as extinct, rate may be 25-45,000 times background extinction rate.* • The pathogenic fungus Batrachochytrium dendrobatidis, which causes Chytridiomycosis is responsible for major population declines.
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- Descrição
- Degree Zoology (Animal Evolution and Diversity) FlashCards sobre Amphibians, criado por Elena Cade em 05-01-2018.
- Criado por
- Elena Cade
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