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CHAPTER 3
CLASSIFICATION OF VERTEBRATES
Objectives
At the end of the discussion, each student is expected to:1. classify the representative chordates into class, order, genus, and species;2. state the common and scientific names
of representative vertebrates; and3. name one distinct characteristic of each taxon to differentiate it from another taxon.
Topic Outline:
A. Fish and Fishlike Animals:1. Class Agnatha2. Class Placodermi3. Class Chondrichthyes4. Class Osteichthyes
B. Vertebrates with Limbs:
1. Class Amphibia2. Class Reptilia3. Class Aves4. Class Mammalia
Vertebrate Taxa
About 50,00 known species are animals with vertebral columns
The classification scheme used in this chapter is a conventional “natural classification”, which means it is based on similarity of structure, the geologic record, rationality, and intuition.
The chief vertebrate taxa are classes, subclasses, superorders, order, suborders, families, genera, and species.
Vertebrate Taxa
There are eight recognized extant classes of vertebrates:
Myxini - hagfishes Cephalaspidomorpha - lampreys Chondrichthyes - cartilagenous fishes Osteichthyes - bony fishes Amphibia - frogs, toads, salamanders, and
caecilians Reptilia - turtles, snakes, lizards,
crocodilians Aves - birds Mammalia - mammals
Vertebrate Taxa
The vertebrate taxa can be grouped based on their general habitat requirements:
Pisces - collective term for all fishes; includes Myxini, Cephalaspidomorpha, Chondrichthyes, Osteichthyes
Tetrapoda - collective term for the terrestrial vertebrates; they have four feet unless some have been secondarily lost or converted to other uses. Includes Amphibia, Reptilia, Aves, and Mammalia
Vertebrate Taxa
Based on their feeding habits: Agnatha - jawless vertebrates, including
Myxini and Cephalaspidomorpha Gnathostomes - vertebrates with jaws
derived from the mandibular arch, which may have (in primitive vertebrates) supported gills. Includes Chondrichthyes, Osteichthyes, Amphibia, Reptilia, Aves, and Mammalia.
Vertebrate Taxa
Based on their embryonic characteristics Anamniotes - vertebrates that lack an
amnion, or extra embryonic membrane that surrounds the embryo and encases it in amniotic fluid. Includes Myxini, Cephalaspidomorpha, Chondrichthyes, Osteichthyes, Amphibia.
Amniotes - vertebrates that possess an amnion. Includes Reptilia, Aves, and Mammals.
Mammalia
Gnathostomes
Tetrapods
AmniotesAves
Reptilia
Amphibia
Anamniotes
Osteichthyes Fishes
Chondrichthyes
Placodermi*
Acanthodii*
Agnatha* Agnathostomes
Major categories of vertebrates
Vertebrate Taxa
Binomial nomenclature as introduced by Carl von Linne (Linnaeus) has enabled all zoologists all over the world to understand one another.
Binomial designation for a species was introduced in the 10th edition(1758) of his book, Systema Naturae
Scientific name of an animal is made up of generic and specific names, or the genus and the species.
Fish and Fishlike Animals
Class Agnatha
Include 2 groups of jawless fishes: ostracoderms and cyclostomes.
Common characteristics: • no jaws • no paired appendages • a completely cartilaginous skeleton • a single nostril • 6 - 14 external or concealed gill slits • a persistent notochord • a two-chambered heart
Class Agnatha
Orders Osteotraci, Anapsida, Heterostraci- extinct, with an
armor of heavy plates, and commonly called ostracoderms.
Class Agnatha
Order Cyclostomata- round-mouthed fishes- cylindrical body and well developed fin- scales absent, soft skin- jaws are absent-suctorial mouth, with horny teeth- single nasal aperture- no appendages- 6 to 14 pairs gill pouches
Class Agnatha: O. Cyclostomata
Suborder MyxinoideaHagfishes and slime eelsTerminal mouth with 4 pairs of tentaclesPartially hermaphroditicLive in temperate, marine deep water Feed on detritus and carrion, as well as
polychaete worms Tentacles around their mouths are used in
locating prey Myxine, Blellostoma
Class Agnatha: O. Cyclostomata
Myxine (hagfish) Pacific hagfish trying to hide under a rock
Class Agnatha: O. Cyclostomata
Suborder Petromyzontiacommonly called the lampreyssuctorial mouth with horny teethnasal sac is not connected to mouth7 pairs of gill pouchestemperate, anadromous (hatch/breed in fresh
water, mature in marine and freshwater) parasitic as adults - attach to other fishes with their
suction-like mouths and rasp a hole in the skin buccal glands secrete an anticoagulant to ensure
free-flowing food source larvae are called ammocoetes
Class Agnatha: O. Cyclostomata
Suborder Petromyzontia
parasitic marine/aquatic animal with a toothed, funnel-like sucking mouth.
Class Agnatha
Lampreys attached to a lake trout
Note:
In other sources, Agnatha is a superclass.Hagfishes are classified under Class Myxini,
Order Myxiniformes.Lampreys are classified under Class
Cephalaspidomorpha, Order Petromyzontiformes
Class Placodermi
Armored prehistoric fish
The first jawed fishesWith full size hyoid gill
slit.With paired pectoral
and pelvic finsWith an armor of bony
scales and cartilaginous skeleton.
Some skeleton maybe ossified.
Class Chondrithtyes
Cartilaginous fishesVentral mouth and paired nostrils Skeleton completely cartilagenous with no
endoskeletal bone No swim bladder Scales dermal placoid when present Gill arches internal to gills Freshwater and marine species
Class Chondrithtyes
Subclass Elasmobranchii 5 - 7 gill openings plus spiracle anterior to first
gill upper jaw not attached to braincase teeth derived from placoid scales, deciduous and
continually replaced claspers present in males, internal fertilization,
ovoviviparous (egg contained within the uterus, where the young develop and then hatch as miniature adults) or viviparous (embryos develop internally and then emerge as a miniature adult)
Class Chondrithtyes: SC Elasmobranchii
Order SqualiformesTrue sharks Almost purely
predaceous/marine Heterocercal tailfin -
caudal fin is longer on the dorsal side than on the ventral side
Squalus
Class Chondrithtyes: SC Elasmobranchii
Order RajiformesRays, skates, sawfishes Greatly flattened bottom
dwellers Scales not over entire
body Pectoral fins winglike Crushing teeth - mollusk
eaters Spiracles greatly enlarged Oviparous - produce an
egg pouch covered in a very tough shell
Class Chondrithtyes
Subclass Holocephali
Chimaeras or rat fishes
upper jaw fused to braincase
flat, bony plates instead of teeth
operculum covering gillslits
strictly marine, feeding on mollusks
Class Osteichthyes
Bony fishes Endoskeleton made up of bone Jaws and paired appendages Gill arches internal to gills Gills covered by bony operculum Dermal scales not placoid Many forms have swim bladder Appeared in Devonian - dominant vertebrates
since mid Devonian Arose in freshwater, moved into saltwater
Class Osteichthyes: S.C. Sarcopterygii
Subclass Sarcopterygii: species previously believed to be extinct, such as the coelacanths and lungfish.
Fleshy lobed fins so that fin rays do not articulate directly to girdles
Internal and external nares Many retain the heterocercal tail, others with
diphycercal tailWith rounded or rhomboid scalesThe coelacanth is represented by a single
species that lives off the Comoro Islands near Madagascar
Order CrossopterygiiOrder Crossopterygii Lobed-finned fishLobed-finned fish
Paired fins with internal skeleton of basic tetrapod type
Presence of maxillae, premaxillae, and spiracle
Scales large and heavily overlapped
Three lobed diphycercal tail
Intestine with spiral valve
Class OsteichthyesS.C. Sarcopterygii
Order DipnoiOrder Dipnoi LungfishLungfish
Median fins fused to form diphycercal tail
Lobed or filamentous finsCycloid type of scalesMaxillae, premaxillae,
and spiracle absentSingle or paired air
bladder for breathingIntestine with spiral
valve
Class Osteichthyes: S.C. Sarcopterygii
Class Osteichthyes: S. C. Actinopterygii
Subclass Actinopterygiiray-finned fish fin rays attach directly
to girdles internal nostrils - nares
absent Nasal sacs open to the
outsidesingle gas bladder One dorsal finWithout cloacaknown from Devonian
Order Chondrosteigeneral primitive
form typically small skeleton primarily
cartilage heterocercal tail ganoid scales most died out by end
of Mesozoic
Suborder PolypteriniSuborder Polypterini PolypterusPolypterus
Ossified skeletonDorsal fin divided into
8 or more finletsSlender body with
thick ganoid scalesLobed pectoral finsDiphycercal caudal finVentral air bladder
with two lobes
Class Osteichthyes: S. C. Actinopterygii
Suborder AcipenseroideiSuborder Acipenseroidei Polyodon (paddlefish)Polyodon (paddlefish)
Ossified dermal skull and unossified chondral skull
Endoskeleton mostly cartilage; body mostly scaleless except for rows of bony scutes (ganoi)
Mouth on underside of head, no teeth
Heterocercal tail, with spiral valve
Class Osteichthyes: S. C. Actinopterygii
Class Osteichthyes: S. C. Actinopterygii
Order HolosteiSkeleton moderately ossifiedWith fairly well developed vertebral centraGanoid to cycloid scalesAbdominal pelvic finsDeficient spiracleSingle air bladder with conus arteriosusVestigial spiral valve
Suborder LepidosteoideiSuborder Lepidosteoidei Lepidosteus (gar fish)Lepidosteus (gar fish)
With thick ganoid scales of rhombic shape
Shortened heterocercal tail
Mostly extinct
Class Osteichthyes: S. C. Actinopterygii
Suborder AmioideaSuborder Amioidea Amia (bowfin)Amia (bowfin)
Scales tend to be thin and round to cycloid type
Homocercal typeBilobed swim bladder
which may serve for respiration
Mostly extinct
Class Osteichthyes: S. C. Actinopterygii
Class Osteichthyes: S. C. Actinopterygii
Order TeleosteiTypical bony fishesSkeleton almost
completely ossifiedVertebral centra
completeThin cycloid or ctenoid
scalesHomocercal tailTerminal mouthNotochord a mere
vestige
Pelvic fins often displaced forward
No spiracleSingle, dorsal air
bladderVestigial conus
arteriosusWithout spiral valve
Class Osteichthyes: S. C. Actinopterygii
Class Osteichthyes
VERTEBRATE WITH LIMBS
Terrestial or aquaticLimbs serve as locomotory appendages and
lungs as respiratory organsVertebral column terminates in a tail,
sometimes absent, or in a horizontal finHeart with 2 atriaWith internal nares
CLASS AMPHIBIA
Arose from Crossopterygian, Rhipidistian ancestors
Three extant orders, two extinct subclasses Lungs and skin used as adult respiratory organs Gills present in larvae, retained into adulthood
in some neotinic forms (salamanders) Heart with two atria and one ventricle - "three
chambered" Skin is naked or with bony dermal elements Ectothermic - must regulate body temperature
by moving to different microclimates within its environment
Class Amphibia
Group includes smallest terrestrial vertebrates up to some 5’ in length
Name implies continued tie to water - eggs must be laid in water or at least in very moist environment; young develop as gill breathing, water-dwelling tadpoles
Embryos lack an amnion, but eggs are laid in a jelly-like protective coating
Class Amphibia
Order LabyrinthodontiaExtinct amphibians that constituted some
of the dominant animals of Late Paleozoic and Early Mesozoic times (about 350 to 210 million years ago).
They are considered to include the first vertebrates known to live on solid ground, and to have been ancestral to at least some of the groups of modern amphibians and a bridge to the reptiles.
Class Amphibia: O. Labyrinthodontia
Class Amphibia: Order Urodela
Tail maintained throughout life Limbs 1 -2 "normal" pairs Elongated trunk and long tail Can retain larval characteristics (flattened,
shovel-shaped head, fleshy tail, external gills) in adult forms (paedomorphic) - the result is a sexually mature individual with many other body parts in the larval or juvenile condition (neoteny)
NecturusNecturus SalamandersSalamanders
Class Amphibia: Order Urodela
Class Amphibia: Order Anura
Loose tail as adults Caudal vertebrae fuse to form long inflexible
urostyle - relates to saltatorial locomotion Long hind limbs developed for saltatorial
locomotion Vocal cords well developed Ear modified for reception of airborne sound
waves
Class Amphibia: Order Anura
Rana esculenta
PipaPipa DiscoglossusDiscoglossus
Class Amphibia: Order Anura
Class Amphibia
Order Gymnophiona or ApodaElongated, snake-like, with no limbs or
girdles No vocal cords or airborne sound detection Some retain scales embedded in skin Notochord persists Minute eyes, lack lids Chemosensory tentacle on head
Class Amphibia: Order Apoda
CLASS REPTILIA
First fully terrestrial vertebrates Development of cleidoic (closed/self-
contained) egg; embryo with extra-embryonic membrane and relatively impermeable shell
Lungs for respiration Heart with two atria and ventricle partially or
totally (Crocodilians) divided One occipital condyle Skin with epidermal scales or bony plates
CLASS REPTILIA
Ectothermic, sometimes called heliotherms because they can regulate body temperature by using solar radiation
First appeared in late Paleozoic, so numerous by Mesozoic known as "Age of Reptiles"
Class Reptilia: Subclass Anapsida
Order CotylosauriaExtinct reptilesResemble the most
primitive extinct amphibians
Class Reptilia: Subclass Anapsida
Order CheloniaRibs modified along
with epidermal plates to form shell - carapace and plastron
Girdles inside ribs Jaws covered with
horny epidermal plates, no teeth
Little change since Triassic
Class Reptilia
Subclass Ichthyopterigia
Order IchthyosauriaExtinctSubclass
SynaptosauriaOrder SauropterygiaExtinct
Plesiosaur
Class Reptilia: Subclass Lepidosauria
Diapsid or modified diapsid skullSkin with horny scalesOrder RhynchocephaliaLong-tailed lizard-like reptiles with weak limbsVertebrae amphicoelus with persistent intercentraWith abdominal ribsParietal eye fairly well developed and easily seenAnus and transverse slitMostly extinct
Sphenodon (tuatara)Sphenodon (tuatara)
Class Reptilia: Subclass Lepidosauria
Class Reptilia: Subclass Lepidosauria
Order SquamataContains most modern reptiles Lizards known from Cretaceous, snakes in
Cenozoic Skull has lost one or both temporal regions Vertebrae usually procoelous Abdominal ribs usually greatly reduced or absent Body covered with horny epidermal scales Quadrate bone moveable Teeth set in sockets
Suborderm LacertiliaSuborderm Lacertilia
The lizardsWell differentiated
appendicular musclesLimb girdles always
present, reduced in limbless forms
Skull with 1 temporal fossa
With mandibular symphysis
Class Reptilia: Subclass Lepidosauria
Suborder OphidiaSuborder Ophidia
SnakesLimbs and girdles
absent, except remnants of pelvis in some
Skull has lost temporal fossae
No mandibular symphysis
Ligamentsts permits wide gape
Class Reptilia: Subclass Lepidosauria
Suborder AmphisbaeniaSuborder Amphisbaenia
Subterranean lizards, mostly limbless
With annulated body.
eardrum and eyes covered with opaque skin
Class Reptilia: Subclass Lepidosauria
Class Reptilia: Subclass Archosauria
Diapsid skull Tending to bipedal gait with ossified changesInclude flying forms Contains dinosaurs and ancestors to birds
Order ThecodontiaOrder Thecodontia ArchosaurArchosaur
The stem archosuarsTeeth set in deep
pocketsHad pneumatic
bonesWith long neck and
tailExtinct
Class Reptilia: Subclass Archosauria
Class Reptilia: Subclass Archosauria
Order CrocodiliaAlligator, Caiman, and CrocodilesQuadrate fixed Bony plates embedded in epidermis Teeth set in sockets Abdominal ribs present in Gastralia Ventricles completely separated Developed secondary palate “Crop" similar to birds
CrocodileCrocodile AlligatorAlligator
Class Reptilia: Subclass Archosauria
Class Reptilia: Subclass Archosauria
Order PterosauriaFlying reptiles
Class Reptilia: Subclass Archosauria
Order SaurichiaDinosaurs with
reptile-like pelvis
Class Reptilia: Subclass Archosauria
Order OrnithischiaDinosaurs with bird-
like pelvis
Class Reptilia: Subclass Synapsida
Mammal-like reptilesOne lateral temporal
fossaOrder PelycosauriaEarly synapsids
www.dinocasts.com/prod_catalog.a...2520DESC
Class Reptilia: Subclass Synapsida
Order TherapsidaLate synapsidsMammalian
precursors
hoopermuseum.earthsci.carleton.c...7pt1.htm
CLASS AVES
Warm-blooded oviparous tetrapods with feathers
One occipital condyleQuadrate freeForelimbs modified to wingsHeart with 2 ventricles, no sinus venosusEmbryo with membranes
Class Aves: Subclass Archaornithes
Earliest birds, derived from bipedal archausar
Long tailMetacarpals separateWith teethArchaopteryx,
Proavis, Archaornis
Archeopteryx
CLASS AVES: Subclass Neornithes
Include all extinct and living birdsFour-chambered heartTail feathers arranged in a fan-like manner around
tail stumpFused metacarpals Epidermal scales on bill, legs, feet Bill instead of teeth; teeth absent in modern forms Modifications for flight include hollow bones,
pectoral appendages modified as wings, air sacs, large eyes and large cerebellum
Modifications for vocalization
Class Aves: Subclass Neornithes
Superorder Neognathae.
Ratites and Carinates
Order Columbiformes( a dove with its young)
Order PelecaniformesOrder Pelecaniformes CormorantCormorant
Pelican
Class Aves: Subclass Neornithes
Order AnseriformesOrder Anseriformes Swan and Geese Swan and Geese
Duck
Class Aves: Subclass Neornithes
Order FalconiformesOrder Falconiformes Eagle and vultureEagle and vulture
Hawk
Class Aves: Subclass Neornithes
Order GalliformesOrder Galliformes
Class Aves: Subclass Neornithes
Order PsittaciformesOrder Psittaciformes ParoquetParoquet
Parrot
Class Aves: Subclass Neornithes
Class Aves: Subclass Neornithes
Largest order of birdsPerching birds
Order Passeriformes
CLASS MAMMALIA
Possess hair/fur Mammary glands to nourish young Viviparous (oviparous in one order) Two occipital condyles Zygomatic arch and secondary palate Single dentary bone in lower jaw Dentary-squamosal jaw for articulation Muscular diaphragm Arose from synapsid reptiles which branched
off at base of reptilian tree
Class Mammalia: Subclass Prototheria
Egg laying mammalsMammary glands without nipplesPectoral girdle with separate precoracoid,
coracoid, and interclavicleScapula with spineOviducts separateWith cloaca
Class Mammalia: Subclass Prototheria
Order MonotremataThe monotremesDuckbilled platypuses
and echidnas
Class Mammalia: Subclass Metatheria
Marsupial mammalsYolk sac serves as
placentaWith an abdominal
skin pouch (marsupium) supported by 2 marsupial bones
Teats open into the marsupium
Precoracoid and interclavicle absent
Coracoid reducedScapula with spineClavicle presentFour molars on each
sideShallow or no cloacaSmooth brainDouble vagina
Class Mammalia: Subclass Metatheria
Order MarsupialiaIncludes the
kangaroos, wallabies, wombats. Opossums, Koala bear
Class Mammalia: Subclass Eutheria
The true placental mammalsViviparous with an allantoic placentaWithuot marsupium or marsupial bonesShoulder girdle like marsupialsMostly three molars on each sideOne vaginaNo cloaca
Class Mammalia: Subclass Eutheria
Order InsectivoraInsect eating mammalsSmall nocturnal or burrowing mammals with
plantigrade clawed feet and often elongated snoutPrimitive dentitionTeeth with sharp cuspsAuditory region incompletely ossifiedUterus bicornuateWith clavicleBrain small and smoothInclude the moles, hedgehogs, flying lemurs
Class Mammalia: Subclass Eutheria
African hedgehog
www.animalcorner.co.uk/animalgro...mal.html
Class Mammalia: Subclass Eutheria
Order ChiropteraThe batsWings are modified forelimbs where the 2nd to 5th
digits are elongated to support a thin integumental membrane for flying
Thumb and hindfeet with clawsWith clavicleSmooth brainTeats ate found on the thoraxWith sharp teethMostly nocturnal, and are capable of true flight
Class Mammalia: Subclass Eutheria
www.rictus.com/viz/photos/seattl...ats.html
Class Mammalia: Subclass Eutheria
Order DermopteraFlying lemursRelated to true bats
and consist of the genus, Galeopithecus or Cynocephalus
They cannot fly but they glide with their parachutes
Galeopterus variegatuswikimedia.org/wiki/Galeo...riegatus
Class Mammalia: Subclass Eutheria
Order PrimataTerrestial or arboreal hairy mammals With 5 digits on each foot, provided with flat nailsPlantigrade gait; forefeet for graspingOrbital and temporal depressions partly or
completely separated by a bony ridgeWith claviclesStomach simpleTeats maybe abdominal, pectoral, or axillaryBrain highly convoluted with very large cerebral
hemispheres
ChimpanzeeChimpanzee Spider MonkeySpider Monkey
Class Mammalia: Subclass Eutheria
Class Mammalia: Subclass Eutheria
Order CarnivoraFlesh-eating mammalsWith well developed incisors and caninesAuditory region is well developed usually
with expanded bullaClavicles reduced or absentSimple stomachConvoluted brain
Class Mammalia: Subclass Eutheria
Order CarnivoraSuborder Fissipedia
Terrestrial carnivores with walking feetStrongly clawedPlantigrade to digitigrade gaitWith six incisorsAnterior cheek teeth sharp, cutting, and
culminating in a special carnassial tooth, behind which molars are broad or reduced.
Suborder FissipediaSuborder FissipediaLeopardLeopardCat and lion
Class Mammalia: Subclass Eutheria
Suborder FissipediaSuborder Fissipediawolves, and civetswolves, and civetsDogs
Class Mammalia: Subclass Eutheria
Suborder FissipediaSuborder Fissipedia Raccoon, bear and otterRaccoon, bear and otterFox, hyena, weasel
Class Mammalia: Subclass Eutheria
Order CarnivoraOrder Carnivora Sea lion and walrusSea lion and walrus
Suborder Pinnepedia
Aquatic mammals with webbed feet
Nails mostly reducedCheek teeth alikeNo carnassial.
Class Mammalia: Subclass Eutheria
Class Mammalia: Subclass Eutheria
Order PerrisodactylaOdd-toed ungulates.Large-hoofed herbivorous mammalsThird digit forming limb axisOther digits smaller or reducedGait unguligradeCheek teeth broad, with grinding ridges
(lophodont)Clavicle absentSimple stomach and no gall bladderConvoluted brainTeats inguinal
Order PerrisodactylaOrder Perrisodactyla
Suborder EquoideaHorses, asses and
zebras
Class Mammalia: Subclass Eutheria
Order PerrisodactylaOrder Perrisodactyla
Suborder TapiroideaFour toes infront,
three behindReduced and wanting
canines and incisorsWith 1 or 2 median
horns of epidermal nature.
Rhinoceruses
Class Mammalia: Subclass Eutheria
Class Mammalia: Subclass Eutheria
Order ArtiodactylaEven-toed mammalsVarious sizesUsually with long legsTwo functional toes on
each foot, usually sheathed in cornified hoof
Many with antlers or horns on head
Reduced dentition, except pigs
Most with a four-compartment stomach, and ruminate or “chew the cud”
Without clavicles and gall bladder
With convoluted brainTeats inguinal or
abdominal
Order ArtiodactylaOrder ArtiodactylaSuborder SuinaNo horns or antlersWith 38-44 teethCanines enlarged as
curved tusksFeet four-toedStomach simple to
two-chamberedPigs, peccaries,
hippopotamus
Class Mammalia: Subclass Eutheria
Order ArtiodactylaSuborder Tylopoda
Order ArtiodactylaSuborder Tylopoda
One upper incisor retained on each side
With ruminating habitStomach complexFeet soft, bearing nailsNet hoovesCamels, llamas,
dromedaries, alpacas
Class Mammalia: Subclass Eutheria
Order ArtiodactylaSuborder Pecora
Order ArtiodactylaSuborder Pecora Deer, antelope, cattleDeer, antelope, cattle
True ruminantsUpper incisors wantingTwo-toed feet,
rudimentary 2nd and 5th toes rarely present
Stomach complex without water cells, with 3 or 4 compartments
Mostly with paired horns
Class Mammalia: Subclass Eutheria
Order ArtiodactylaSuborder Pecora
Order ArtiodactylaSuborder Pecora
Sheep, goat, and giraffe Sheep, goat, and giraffe
Class Mammalia: Subclass Eutheria
Class Mammalia: Subclass Eutheria
Order CetaceaSize, medium to very
largeBody usually torpedo-
shapedLong head, often
pointed, joined directly to body
Some with a fleshy dorsal “fin”
Forelimbs/flippers broad and paddle-like, digits embedded
No claws and hindlimbs
Nostrils on top of headLong tail, ending in 2
broad transverse fleshy flukes and notched in midline
Teeth alike when presentWhalebone or baleen if
teeth are lackingSmall ear openingsSmooth body surfaceNo skin glandsWith blubber under skinComplex stomach
Class Mammalia: Subclass Eutheria
Order CetaceaSuborder
OdontocoetiToothed cetaceansTeeth 2 to 40 in
various speciesDolphins, porpoises
and some whales
Killer whale
Order Cetacea: A porpoise and a dolphin
Class Mammalia: Subclass Eutheria
Order CetaceaSuborder
MystacoetiNo teeth and instead
with whalebone, horny fringes hanging along the edge of the upper jaw
A baleen whale
Class Mammalia: Subclass Eutheria
Order Proboscidea (the elephants)Massive, large head, flat and broad ears, short neck,
body huge, legs pillar-like, thick skin (pachyderm), loose and sparsely-haired
Nose and upper lip along flexible muscular proboscisProboscis contain nasal passages with nostrils at the
tipTwo upper incisors elongated as tusksFeet club-like, toes 5,3,or 4, each with small nail-like
hoofWeight is borne on elastic pad behind toes.
Class Mammalia: Subclass Eutheria
Class Mammalia: Subclass Eutheria
Order Sirenia (manatees or sea cow)Large, body spindle-shapedForelimbs paddle-likeNo hindlimbsTail with lateral flukes, not notchedBlunt muzzle, small mouth, fleshy lipsNo external earsTeeth with enamelFew, scattered hairsComplex stomach
Class Mammalia: Subclass Eutheria
Order Sirenia (manatees or sea cow)
Class Mammalia: Subclass Eutheria
Order HyracoideaSmallFour toes on forelimb,
3 on hindDigits with small
hoofs, except 2nd clawed toe
Ears and tail shortIncisors ½No caninesProcavia (Hyrax)
Class Mammalia: Subclass Eutheria
Order RodentiaUsually smallLimbs with 5 toes and clawsIncisors 1/1 x2 exposed, chisel-like, rootless,
grow continuallyNo caninesWith a gap between incisors and cheek teethNarrow palateJaw motion both back and forth and lateralElbow joint rotates
Class Mammalia: Subclass Eutheria
Order Rodentia Squirrels, marmots, prairie
dogs, beavers, rats, mice, guinea pigs, agoutis, porcupines
Class Mammalia: Subclass Eutheria
Order Xenartha (edentates)
Includes slothsTeeth reduced to
molars in forepart of jaws, or none, no enamel
Toes clawedSmooth brain
A sloth and an armadillo
Class Mammalia: Subclass Eutheria
An anteater
Class Mammalia: Subclass Eutheria
Order Pholidota (pangolins)
Body covered by large overlapping horny plates with sparse hair between
No teeth, tongue slender and used to capture insects
Manis ( pangolin or scaly anteater)
Class Mammalia: Subclass Eutheria
Order Tubulidentata( Aadvarks) Stout body, somewhat piglike, sparsely hairedLong ears and snoutTubular mouth and slender, protrusible tongueMany milk teeth , few permanent teeth, unrooted,
no enamel4 to 5 toes, with heavy claws
Aadvarks
Pika, hare, and rabbitPika, hare, and rabbit
Order LagomorphaSize moderate to smallToes with clawsTail stubbyIncisors chisel likeNo caninesPalate broadJaw motion lateral onlyElbow joint nonrotating
Class Mammalia: Subclass Eutheria
COMPILED BY:PROF. MA. CORAZON P. DE JESUS
End of Parade of the Vertebrates…