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Amphibia | 117, order 4? GYMNOPHIONA or APODA, fk Primitive burrowing forms., 9, Body is elongated eel type., 3, Limbs and tail are absent., 4, Limbs provided with transverse grooves or wrinkles., 5. Copulatory organs are present in males., Example : Icthyophis, Siphonops, Uraeotyphlus., Order 5: CAUDATA or URODELA, 1. Body with distinct, head, trunk and tail., 9. Limbs are of equal size., 3. Skin devoid of scales., 4, Teeth are present in both the jaws., 5, Usually oviparous. :, 6. Larvae are aquatic like adults or resemble adults in form., Example : Ambystoma, Axolotl larva., Order 6: ANURA or SALIENTIA, 1, Body is short and broad., 9. Head and trunk are fused., 3, Neck and tail are absent., 4. Fore limbs are short while hind limbs are jong., 5, Gills are absent. Respiration is by lungs., g, Fertilization is usually external., Examples : Alytes, Pipa, Bombinator, Bufo, Hyla, Rana, Rhacophorus., , Questions, , 1, Write the general characters of Amphibia and classify it upto orders., , Short Answer type Questions, , 1. Parental care jn Amphibia. (Kanpur 2007), , oe

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A ibi 9, PARENTAL CARE ee, , Looking after the eggs or the youn,, , . ig until t 7, om predators 1s known as parental care. Se independent, to defend, generally fall under two categories ; M4, @) pero oe by nests, nurseries or shelters, (2) Direct caring by parents (Figs. 1 and 2), , hods of caring of Amphibia, , Tree frog enlarged, , itting on to, sitting p Eggs laid a Floating foam nest, , on water, , Parent, guarding fronthy mass, Slopping, , tunnel, , Mud nest Tadpoles, , , , , , , , , Water, , , , Fig.1: Parental care in Amphibia. Protection by nests, nurseries or shelters. (A), , i 3 .(A) A tree frog guardin, eggs glued toa leaf overhanging water. (B) Foam nest of Rhacophorus schlegeliin a Acoina haan, near water. (C) Foam nest floating on water. (D) Mud nest of Hyla faber., , , , , , Female _ £998 Parent, , , , , , f Tadpoles, , Burrow (A) “Open, brood pouch, or marsupium, , , , ©) acre | Cem tH), , . 2: Di in Amphibia. (A) Female Ichtl, Ae CENT eed i ‘ Desmognathus fuscus with eggs., , , , thyophis coiling round eggs., , (B) transportation of tadpoles attached to back of a parent. (C) :, , (0) Male Alytes obstetricans carrying eggs around his thighs. (E)A marsupial frog with eggs exposed, , in open brood pouch on back. (F) Notorema.or Gastrotheca, with flap of dorsal brood ere oat to show, eggs. (G) In Pipa, eggs develop completely into individual capsules on back of female., , (H) Froglets inside vocal sacs cut open of male Ahinoderma darwinil., , 1, Protection by Nests, Nurseries or Shelters qitetele, Amphibians have evolved countless interesting methods to give protection, to their defenseless eggs and larvae from predators.

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iversity of Chordates, , : Life and D, 114 | RP Modern Zoology : : ‘, y amphibians lay eggs in Protected, 1,, , 10), ] frogs and toads lay eggs on land near ae, , . nd but on leaves and by,, , Se De a ei Deere lionie, Hylodes eu, ene Beas Rhacophorus malabaricus in ic Ug, their eggs to foliage hanging over water. : E ecihicestiNiingic dia, and Chiromants of Africa also deposit their ae eid ae a frogs, deposit eggs in water that accumulates an epip! ie ae ne aan ne from, reach of aquatic egg predators in their microhabi a os ; P n atching, drop into water beneath to complete their EO ‘ae ‘ ;, , (2) Defending eggs or territories—Males of green ne! ana Clamitang, and other species maintain territories and attack small intruders to defend eggs,, Male or female even guard the eggs. Some tree frogs lay eggs above water May, sit besides the eggs or rest on top of them. Removal of guard frogs may regu}t in, dessication or death of eggs. , (3) Direct development—In some terrestrial or tree frogs such ae, Eleutherodactylus Hyla, the eggs hatch directly into little frogs thus avoiding, , (1) Selection of site—Man, microhabitats on land. Many tropica:, , larval mortality. P, (4) Foam nests—Many amphibians convert copious mucous secretions, , into nests for their young. In the tree frog Rhacophorus the mating couple digs, a hole or tunnel into which eggs are left in a frothy mass to avoid dessication,, During rains hatching tadpoles are washed down the slopping tunnel into pond, or river water for further development. The tadpoles developing in these improvised nests can readily enter water. The female emits huge mucus that she, beats into a foam with her hindlegs to lay eggs. When tadpoles hatch they drop, from foam into water., , (5) Mud nests—In Brazilian tree frog, Hyla fabre, the male digs a little, crater—like hole or nursery in mud in shallow water in which the female lays, eggs. The nest is 30 cm in diameter and 5 to 8cm deep. Tadpoles hatch within, this relatively safer barrier and develop until they are large enough to feed, themselves., , (6) Tree nests—The South American tree frog Phyllomedusa, hypochondrales lays eggs in folded leaf nest with margins glued together by, cloacal secretion. The tadpoles when formed fall straight into water below. Female lays eggs when this cavity is filled with rain water. Here the young develop, relatively free from predators,, , (7) Gelatinous bags—In Phrynixalus biroi large eggs are enclosed in, a sausage shaped transparent gelatinous membranous bag, secreted by female, and left in mountain streams. Salamandrella keyserlingi, a small aquatic, salamander also deposits 50 to 60 small egesin a gelatinous ba g which is fastened, to aquatic plants., , 2. Direct Caring by Parents, In Congo eel, Amphiuma and certain Coecilians like Icthyophis the female, , lays large eggs in burrows i damp soil and carefully guards them by coiling her, body around them until they hatch. The female of salamander, Plethodon als0

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d the eg; hich Amphibia | 115, , ils roun' e eggs which are laid i ‘, , a or beneath a rock. In Bere een pole oF er, around the eggs: us, it is male who coils, , QT ne tadpoles to water—Some species of small frogs (¢.8Phyllobates, rtl roleptis, Pelobates, Denérobates) in both tropical Africa and, South America deposit their eggs on ground. The tadpoles hatching out fasten, Beppo abe of one of the parents with their sucker like mouth and, transpor’ er., , (2) Eggs glued to body—Many amphibians instead of remaining with, the eggs, carry the eggs glued to their body. In the dusky salamander,, Desmognathus fucus, female carries the string of eggs coiled around the neck,, until they have hatched, In Sri Lankan tree frog, Rhacophorus reticulatus, the eggs are glued to the belly of female in the midwife toad Alytes obstetricans, when the female lays eggs, the male entangles them around his hindlegs. He, carries them with him until they are ready to hatch. At that time he releases, the tadpole into nearest water., , (3) Eggs in back pouches—In one group of tree frogs called marsupial, frogs or toads, the female carries the eggs on her back, either in an open oval, depression, a closed pouch or in individual pockets. The eggs develop into, miniature frogs before they leave their mother’s back., , Asimilar adaptation is seen in the completely aquatic Surinam toad, Pipa., In breeding season, skin of females back become thick, vascular, soft and gelatinous. The male presses fertilized eggs against females back where they sink, into individual pits. A hinged cover forms over each egg enclosed in a small, , * capsule. The tiny toads leaving mother are tailless and do not enter water., , (4) Organs as brooding pouches—Rhinoderma darwinii pushes at, least two fertilized eggs into relatively large vocal sacs. Here they undergo complete development to emerge out as fully formed froglets. In west African tree, frogs, Hylambates breviceps, the female carries eggs in the buccal cavity. In, Arthroleptis it is the male who keeps the larvae in his mouth. The only known, case of gastric jnculation in vertebrates is found in Australian frog., , Rheobatrachus silus—The female keeps the egg in her stomach. The, tadpoles are expelled through mouth after metamorphosis. i :, , (5) Viviparity—Some anurans are ovo-viviparous. They retain eggs in, the oviducts and females give birth to living young. The European Salamander, Salamandra produce 20 or more small young while the Alpine salamander, s, atra gives birth to one or two fully developed young. Viviparity is widespread, , in order Gymnophiona and 3 out of 4 families have this mode of reproduc, tion, Common examples are Typhlonectes, Geotrypetes, Dermfphis etc., , General Characters of Amphibia, , 1. Cold blooded vertebrates. : : ;, 9. Skin smooth or rough, rich in glands which keeps it moist., 3. Scales if present are hidden in the skin., , 4, Skull articulates with the atlas by two occipital condyles.