January 29, 2018 | Author: Anonymous | Category: Science, Biology, Zoology, Entomology
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Short Description

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Order Apoda Caecilians -no limbs or girdles -burrowers (fossorial) -short or absent tail -terminal vent -no or few caudal vertebrae -small eyes -eyes under the skin or under the skull -annular grooves have tiny dermal scales -no gills in adults -protrusible male sex organs (called phallodeum); thus internal fertilization -tentacle between eye and nostril -outgrowth of the brain, tactile in function - 6 families; 33 genera and 163 species

Skull completely roofed, except opening for sense organs, little kinesis

Skull with temporal region openings; slightly kinetic

Family Rhinatrematidae


American Tailed Caecilians - 2 genera; 9 species - most basal group - eyes visible externally; in bony sockets beneath skin -tentacle arises near anterior edge of eye -short tail -200 – 300 mm TL -oviparous -deposits aquatic eggs


Family Ichthyophiidae Asian Tailed Caecilians - SE Asia, India and Indonesia - oviparous - conspicuous annuli; mostly 200-300 mm TL - Ichthyophis glutinosus -very common -forest lowland streams -burrow in banks, lay 15-20 eggs in burrows -female coils around eggs -larvae hatch and enter water -larvae are gilled -upon transformation lose gills and become worm-like

Family Caecilidae Tailless Caecilians 21 genera -Seychelles -SA, Africa, and SE Asia -oviparous or viviparous -larval period 10-12 months -terrestrial as adults -no tails



Family Typhlonectidae Water Caecilians 5 genera; 13 species -small eyes are hypodermal - dermal scales absent in the grooves - sensory tentacle small; closer to nostrils than the eye -largest caecilians - 300 mm-800 mm -S. America - all viviparous -R. Nussbaum at U of Mich

Family Scolecomorphidae 1 genus - Scolecomorphus

-E and W Africa (sub-Saharan Africa) -tailless; eye covered with bone -large tentacle can be extended -oviducts w/ small eggs but bigger embryos -ovoviviparous-developing embryo nourished by mom

Family Uraeotyphlidae – Kerala Caecilians 1 genus – Uraeotyphlus - 200 – 300 mm TL - scales present in annular grooves - short tail - eat earthworms and insects

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