Farid K. Muzaki, S.Si., M.Si

Jurusan BIOLOGIFMIPA – ITS Surabaya

V E R M E SV E R M E SThe Platyhelminthes – The Nematode – The Annelid

Taxonomy of Animalia – SB091321

Phylum 1: PLATYHELMINTHESy

Parasitic or free-living, unsegmented wormsTriploblastic, acoelomate, bilaterally symmetrical; flattened dorsoventrallydorsoventrallyComplex, though incomplete, gut usually present; gut absent in some parasitic forms (Cestoda)Cephalized, with a central nervous system comprising an anterior cerebral ganglion and (usually) longitudinal nerve cords connected by transverse commissures (ladder like nervous system)by transverse commissures (ladder-like nervous system)With protonephridia as excretory/osmoregulatory structuresHermaphroditic, with complex reproductive systemHermaphroditic, with complex reproductive system

Diversity of PLATYHELMINTHES

T b ll iTurbellariaDugesia (Planaria), Pseudoceros, Thysanozoon

MMonogeneaGyrodactylus, Dactylogyrus

T dTrematodaEchinostoma, Fasciola, Schistosoma

C dCestodaTaenia, Hymenolepis

PLATYHELMINTHES: The bauplan

Class 1: Turbellaria

Planaria (TURBELLARIA)

Class 1: Turbellaria

Pseudoceros

Acanthozoon Thysanozoon

Class 2: Monogenea

Gyrodactylus

Class 3: Trematoda

Chlonorchis sinensis

Schystosoma mansoni

Life cycle of Chlonorchis sinensis

metacercarial cyst

cercaria

dimiracidium

redia

sporocyst

Class 4: Cestoda

Taenia pisiformis (dog tapeworm)

Life cycle of Taenia saginata

Evaginated cysticercus in upper intestine

Invaginated cysticercus

Shelled larva in feces

Cysts in muscle (beef)

Phylum 2: NEMATODA (NEMATA)

Triploblastic bilateral vermiform unsegmented blastocoelomate

y ( )

Triploblastic, bilateral, vermiform, unsegmented, blastocoelomateBody round in cross section and covered by a layered cuticle; growth in juveniles usually accompanied by cuticular sheddingWith unique cephalic sense organs called amphids; some have caudal sense organs called phasmidsG l h d d ll Gut complete; various mouth structures arranged in radially symmetrical patternWithout special circulatory or gas exchange structuresWithout special circulatory or gas exchange structuresBody wall has only longitudinal muscles (no circular muscles)Epidermis cellular or syncitial, forming longitudinal cords housing p y , g g gnerve cords

Dioecious; males commonly with “hooked” posterior endWith unique cleavage pattern; not unambiguously radial or spiralInhabit marine, freshwater, and terrestrial environments; some are free-living some parasiticare free living, some parasiticClass Adenophorea (Aphasmida): Strongyloides, Trichinella, Trichuris

Class Secernentea (Phasmida): Anchylostoma, Wuchereria, Ascaris, Necator

Nematoda bauplanp

Posterior end of male Nematode

Life cycle of Trichinella spiralis, a parasitic nematode in human intestine wall (sucking blood)

Life cycle of Necator

Some free living Nematodesg

Some free living Nematodes

Desmocolex

Greefiella Chromadoria

Phylum 3: ANNELID

S hi l bil t ll t i l t d w

y

Schizocoelous, bilaterally symmetrical, segmented wormsDevelopment typically protostomous; segments arise by teloblastic growthgWith a closed circulatory system; respiratory pigments include hemoglobin, chlorocruorin and hemerythrinNervous system well developed, with a dorsal cerebral ganglion, circumenteric connectives, and ventral ganglionated nerve cord(s)Most possess metanephridia or less commonly protonephridiaMost possess metanephridia or, less commonly, protonephridiaWith lateral, segmentally arranged epidermal chaetaeHead composed of presegmental prostomium and peristomiumHead composed of presegmental prostomium and peristomium

Di i h h diti h h t i ti Dioecious or hermaphroditic; many have a characteristic trochophore larva (secondarily lost in some groups)Marine, terrestrial, and freshwater species, , pClass Polychaeta: With numerous chaetae (often called setae) on the trunk segments; most with well developed parapodia; prostomium and peristomium often bear sensory organs (palps tentacles cirri) or extensive feeding and gas often bear sensory organs (palps, tentacles, cirri) or extensive feeding and gas exchange tentacular structures; foregut often modifiedas eversible stomodeal pharynx (proboscis), sometimes armed with chitinous jaws; reproductive structures simple, often transient; without a clitellum; most are dioecious; development often simple, often transient; without a clitellum; most are dioecious; development often indirect, with a free-swimming trochophore larva; mostly marine; errant, burrowing, tube-dwelling, interstitial, or planktonic; some live in brackish water, a few inhabit fresh water or are parasitic; Arenicola, Capitella, Eunice, Diopatra, Nereis, Sabellastarte, Spirobranchus, Terebella

Class ClitellataClass Clitellata:subclass Oligochaeta: With few chaetae; cephalic

d d b d ll hsensory structures reduced; body externally homonomousexcept for clitellum; Lumbricus, Tubifex

b l Hi di id B d h f d b f subclass Hirudinoidea: Body with fixed number of segments, each with superficial annuli; chaetae few or absent; heteronomous with clitellum and a posterior and absent; heteronomous, with clitellum and a posterior and usually an anterior sucker; most live in freshwater or marine habitats, a few are semiterrestrial; ectoparasitic, predaceous, or scavenging; Hirudo, Haemadipsa

Class 1: Polychaetay

Life habit of Polychaeta

Nereis Nereis

Spirobranchus giganteus

Sabellastarte

Lumbricus

Tubifex (Tubificidae)

Branchiura (Tubificidae)

HirudoHirudo

AcanthobdellaHaemadipsa

HIRUDINOIDEA

Tubifex Lumbricus

LumbriculusHirudo

T i K ihTerima Kasih