Chapter 5 Coelenterata

1. Chapter 5 Coelenterata 浮游水母类的一般形态、分类、 生物学与经济意义

2. General features • two primary lays: outer ectoderm and inner endoderm • radial symmetry Class Hydromedusae Class Scyphomedusae

3. §5.1 MorphologyHydromedusae

4. External features • Form：polypoid and medusoid • Morphology • umbrella: exumbrella and subumbrella • Velum and pseudovelum • Manubrium and mouth lips • Tenacle: marginal and oral tentacles • Nematocyst： • morphology: operculum, capsule and thread • classification

5. Internal features • Gastrovascular System： gastrovascular-cavity • Muscular System：radial and circular fibers • Nervous and Sensory Cell： • nerve net • ganglion cell • neurosecretory cell

6. √Sensory Organ • pigment cell • statocyst: • open marginal vesicle • closed marginal vesicle • free marginal sensoty club • enclosed marginal sensoty club • Reproduction： • dioecious，gonads situated on the radial canals or inside stomach

7. §5.2 Class Hydromedusae

8. Hydromedusae • >2000 species，6 orders： • velum • presence or absence ocelli and statocysts • position of gonads • type of life cycle

9. (一) Order Anthomedusae • 本目有22科，介绍常见4个科。 • 1、Family Tubulariidae • Euphysora • 2、Family Bougainvilliidae • Koellikerina • 3、Fmaily Velellidae：one genus，one species • 4、Family Randeidae • Leuckartiara厦门隔膜水母

10. （二） Order Leptomedusae • 本目12科，我国记录9科，介绍常见4科。 • 1、Family Campanulariidae: • Phialidium: P. chengshanense • Obelia • 2、Family Eirenidae: • Eirene • 3、Family Eutimidae • Eutima • 4、Family Aequoreidae • Aequorea

11. 本目共4科。 Family Moerisiidae Tiaricodon （三） Order Limnomedusae

12. （四） Order Trachymedusae: • Family Geryoniidae: Liriop: L. tetraphylla • Family Rhopalonematidae Aglaura: A. hemistoma

13. （五） Order Narcomedusae • Family Aeginidae: • Solmundella bitentaculata • Aegina citrea

14. （六） Order Siphonophora • Specialized group of medusae with polymorphic colony

15. Morphology of Siphonophora • Modified medusoid and polypoid inviduals： • Polypoid zooids： • gastrozooids； • dactylozooids； • gonozooids； • Medusoid forms： • nectophore； • pneumatophore； • gonophore； • bract；

16. Classification of Siphonophora: • Suborder Disconanthae ：Family Porpitidae • Suborder Cystonectae：Family Physaliidae： • Suborfer Physonectae：Family Agalmidae Agalma elegans • Suborder Calysophorae ：Family Diphyidae • Diphyes • Muggiaea

17. §5.3 Class Scyphomedusae 一、Morphology

18. （一） 外部形态 • Lappet • Sense Organs： rhopalium, ocelli • Oral arms： • 附属物：感觉功能。 • 生殖下穴： • Marginal Tentacles：solid or hollow

19. （二） 内部形态： • Digest system； • Gastrovascular system： • Nervous system and sense organs： • Reproduction：diovcious

20. 二、Clasification

21. 1 Key to Class Scyphomedusae 1 Cubical umbrella form.................................Cubomedusae Umbrella not cubical form...........……….........……...…..2 2 Exumbrella with a circular, coronal furrow....Coronatae Exumbrella without a furrow.........…........……………...3 3 Oral arms free.............................................Semaeostomeae Oral arms fused.............................................Rhizostomeae

22. §5.4 Biology and Significance

23. Biology

24. （一）Distribution • Cold water species: Cyanea capillata • Warm water species: Aglaura hemistoma,Velella velella, Porpita porpita, Physalia physalia etc. • Coastal species: many species of Anthomedusae, Leptomedusae, Limnomedusae, Semaeostomeae and Rhizostomeae

25. （二） Feeding habits

26. （三） Reproduction • dioecious without sexual dimorphism • 1 sexual cells； • 2 fertilization； • 3 development;

27. （四） Life cycle： • Alternation of generations： • zygote → blastula → planular larva → attachment → hydranth • Without alternation of generations：

29. Significance • Beneficial • Fisheries • Medical use • Harmful