Phylum ChordataClass Reptile

DWI CANDRA PRATIWI, M.Sc

FAKULTAS PERIKANAN DAN ILMU KELAUTANUNIVERSITAS BRAWIJAYA

2014

Introduction

• Reptiles (Reptilia) are members of a class of air-breathing, ectothermic (cold-blooded) vertebrates which are characterized by skin covered in scales and/or scutes.

• They are tetrapods, either having four limbs or being descended from four-limbed ancestors

General characteristics

• Internal fertilization– increases chances of survival

• Cold blooded – ectothermic– Activity is regulated by the temperature of the

environment– Restricted from cold water for this reason

• Well developed lungs• If legs – 2 pair with claws (cakar/kuku)• Scales (sisik) or plates

Four living order are typically recognized:

1. Crocodilia (crocodiles, gavials, caimans, and alligators): 23 species

2. Sphenodontia (tuataras from New Zealand): 2 species

3. Squamata (lizards, snakes, and worm lizards): approximately 9,150 species.

4. Testudines (turtles, terrapins and tortoises): over 300 specie

General Characteristics

• Amniotic egg – shelled– Shell – porous, prevents rapid water loss–Chorion – lines shell, gas exchange–Amnion – encloses embryo–Allantois – develops from embryo; carries

on embryonic respiration and excretion– Yolk sac – contains food supply

• This class included the dinosaurs

General characteristics

• Tuatara (Sphenodon) – only living example• Found in New Zealand• Resembles large lizard• Parietal eye – third eye covered by skin; senses

sun’s radiation

Order Rhynchoephalia

• Turtle – sea turtles– 230 species– Webbed feet– Soft-shelled (streamlines)– Omnivorous – eat both plants and animals

Order Chelonia

Sea Turtles

• Bodies are enclosed in a carapace – shell• Cannot retract their head into the shell• Forelimbs are modified into flippers (sirip)• Only 7 species exist• Lack teeth but have strong jaws for biting• Females come up onto the beach at night to lay eggs

in the sand• Babies hatch and return to the sea• Turtles are thought to return to same beach they

were born on to lay their own eggs

Order Chelonia

Di dunia saat ini hanya ada tujuh jenis penyu yang masih bertahan, yaitu :

Penyu hijau (Chelonia mydas)Penyu sisik (Eretmochelys imbricata)Penyu Kemp’s ridley (Lepidochelys kempi)Penyu lekang (Lepidochelys olivacea)Penyu belimbing (Dermochelys coriacea)Penyu pipih (Natator depressus)Penyu tempayan (Caretta caretta)

Dari ketujuh jenis ini, hanya penyu Kemp's ridley yang tidak pernah tercatat ditemukan di perairan Indonesia.

Class : Reptilia: ReptilesOrder : Chelonia: Turtles and TortoisesFamily : Chelonidae: Marine TurtlesScientific Name: Natator depressus (Penyu pipih)Diet : sea cucumbers, soft corals, jellyfish.Size : < 1 m in lengthConservation Status: vunerableHabitat: near continental shelf, shallow, soft bottom sea bedsRange : northern part of Australia

Flatback turtles are usually found in bays, shallow, grassy waters, coral reefs, estuaries and lagoons on the northern coast of Australia and off the coast of Papua New Guinea.The species may feed off Indonesia and Papua New Guinea, but it nests only in Australia

Class: Reptilia: ReptilesOrder: Chelonia: Turtles and TortoisesFamily: Chelonidae: Marine TurtlesScientific Name: Chelonia mydasDiet: seagrass and algaeSize: ~500lbsConservation Status: threatenedHabitat: high energy ocean beaches, pelagic habitat, benthic feeding grounds in relatively protected watersRange: throughout world in all tropical and subtropical oceans

Green turtle

C. mydas distribution. Red circles are known major nesting sites. Yellow circles represent minor nesting locations.

Class : Reptilia: ReptilesOrder : Chelonia: Turtles and Tortoises Family : Chelonidae: Marine Turtles Scientific Name: Eretmochelys imbricata (Penyu sisik)

Diet : ShellfishSize : 76 - 91 cm (30 - 36 in) Conservation Status: Endangered Habitat : coral reefs, rocky coasts Range : Tropical Atlantic, Pacific and Indian Oceans; Caribbean

Another model of the possible distribution of E. imbricata. Red circles represent known major nesting sites. Yellow circles are minor nesting sites.

Class : Reptilia: ReptilesOrder : Chelonia: Turtles and TortoisesFamily : Chelonidae: Marine TurtlesScientific Name : Caretta caretta (Penyu tempayan)Diet : CrustaceansSize : 76 - 102 cm (30 - 40 in) Conservation Status :Vulnerable Habitat : coasts, open sea Range : Temperate and tropical areas of the Pacific, Indian and Atlantic Oceans

Loggerhead

Their shell is a reddish brown color, and their skin ranges from yellow to brown. The name loggerhead comes from their disproportionately large head. The loggerhead sea turtle holds the title of the world's largest hard-shelled turtle

Physiology:

•Poikilothermic (cold blooded)•Skin has scales•Speed- 35 mph•Breath holding- 2 hrs, when sleeping or resting•Maturity- 10-50 yrs for green•Cannot retract heads like terrestrial turtles•Lacrimal gland- salt secretion (drinks seawater)

•Has both internal and external skeleton- provided protection and support for organs•Fused ribs (tulang rusuk menyatu)•Powerful sense of smell- find natal beach•No ears, but can perceive low frequency sound and vibrations•Male & female- difference in tail size; males tail extends past rear flippers, females is shorter

Anatomy

Mating- at seaMigration- occurs in late spring; female is accompanied by male

Green sea turtles migrate as far as 800 miles from feeding area to nest in Northwestern Hawaiian Islands

Egg laying behavior- return to same beach (natal beach)

Kemps Ridley nesting

Usually nest at night

Front flippers dig pit, rear flippers carve out burrow

Turtle nestCross section

Egg tooth- used to chip away at shell

Group effort to get out of nest- emerge at night (safer) and head towards brightest light

Artificial lights- confuse hatchlings

Clutch size- about 100 eggs & covers pit with sand

Egg incubation- 2 months depending upon species

Sex determined by temperature- males lower temp, females higher temp

Leatherback hatching Kemps Ridley hatchlings

Conservation Status

1. Endangered-facing a very high risk of extinction in the wild

2. Vulnerable -facing a high risk of extinction in the wild

3. Threatened-close to qualifying in one of the above categories

1. International Union for the Conservation of Nature (IUCN), also called the World Conservation Union

2. The Convention on International Trade in Endangered Species (CITES)3. The United States Fish and Wildlife Service.

Harm things to population of marine turtles

Eggs- skunks, raccoons, pigs, lizards, crabs, ants, beetles, fungal and bacterial infections

Hatchlings- birds, mammals, crabs

Adults- sharks, humans

A. HuntersB. FisheriesC. Marine DebrisD. Coastal Development and Habitat DegradationE. Fibropapilloma

Increase sea turtle populations:Ranching- eggs or hatchlings from wild populationsFarming- originally from wild populations, for breeding stock

Law enforcement- in Hawaii, turtles protected under Endangered Species ActRiding or harassing- $100,000 fine + prison timeBringing turtle products into Hawaii- $20,000 + prison time

Fishing regulations- Shrimp Trawlers - incidental catch by commercial shrimp fish nets: drowned 10,000 turtles each yearDrift nets, gill nets Turtle Excluder Device (TED)

Marine Debris- plastic bags, soda can plastic rings, fishing line, oil and tar

Costal development and habitat degradation- noise, light, beach obstructions- affect nesting habitat

Fibropapilloma- virus in Green turtles

Affects ability to feed, see, move about, or breath

May be due to pollutants, blood parasites, or habitat change

Kaneohe Bay (1991)- >50% infected

Marine Iguanas

• Marine lizard endemic to Galapagos islands• Herbivorous: graze on seaweeds• Salt-glands on nose to eliminate excess salt• Recently observed feeding on land for first time• They return to land to escape predators.

• Found mostly in the tropical waters of the Indian and Pacific oceans

• Bodies are laterally flattened and tail is adapted into a paddle

• Range in size between 3 and 4 feet• They are ovoviviparous which means eggs are

internally fertilized and baby hatches inside the mother

• All are carnivorous• Very poisonous

Sea Snakes

Adaptations to life in the sea1. Osmoregulation: skin is impermeable to salts;

salts eliminated by sublingual gland2. Developing a flattened paddle-shaped tail and a

laterally compressed body.3. Reduced metabolic rate and increased tolerance

for low oxygen levels4. Lungs- greatly enlarged5. Gaseous exchange - lungs and the skin.

Sea Snakes

Reproduction:• Not much known about breeding• However, olive sea snake breed in spring; seasonal

courtship displays

Olive Sea Snake

Sea Snakes

Thank you for your attention..