Phylum Cnidaria-Radiate Animals

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Phylum Cnidaria-Radiate Animals • Tissue level of organization • 2 Germ layers • Hydrostatic Skeleton • Gastrovascular Cavity- for digestion • Polymorphism • Polyp (sessile) and Medusa (free-living) stages Class Hydrozoa 1. Lifestyle- Both polyp and medusa stages dominant 2. Reproduction- asexual by budding or sexual 3. 10 tentacles 4. Ex: Obelia, Obelia medusae, Hydra, Hydra reproductive stages Class Scyphozoa- True Jellyfish 1. Lifestyle- Solitary- Medusa-stage dominant 2. Ex: Aurelia, Aurelia lifecycle Class Anthozoa 1. Lifestyle- Polyp stage dominant 2. Gastrovascular cavity divided into mesenteries 3. Ex: Mertidium, Metridium dissection Return to original outline Return to phyla outline Class Hydrozoa Hydra C.S L.S 100X W.M Male Female Return to original outline Return to phyla outline Hydra 40X W.M Return to original outline Return to phyla outline Budding 40X Spermary Ovary 40X Return to original outline Return to phyla outline Obelia Obelia Colony 40X Return to original outline Return to phyla outline Medusae 100x Return to original outline Return to phyla outline Class Scyphozoa Aurelia Lifecycle Planula 100x Schyphistoma 100x Strobila 100x Ephrya 40x Return to original outline Return to phyla outline Aurelia Return to original outline Return to phyla outline Class Anthozoa Metridium LS CS Dissection scope Return to original outline Return to phyla outline Metridium Return to original outline Return to phyla outline Phylum Porifera-The Sponges • Multicellular • Cellular level of organization • No division of labor among cells • No body systems, no organs, no mouth/digestive tract • No germ layers • Pores and canal systems Class Calcarea 1. Spicule type- calcium carbonate 2. Canal system- asconoid, leuconoid and syconoid 3. Marine 4. Ex: Grantia (a.k.a Sycon), Grantia spicules Class Hexactinellida 1. Spicule type- siliceous 2. Canal system- syconoid or leuconoid 3. Marine 4. Ex: Euplectella (Venus’s flower basket) Class Demospongiae 1. Spicule type- Siliceous, spongin 2. Canal system- Leuconoid 3. Marine, except one family 4. Ex: Spongia, Spongilla Representative Porifera Sponge Types: Asconoid- characterized by a simple stalk-like spongocoel surrounded by a single layer of choanocytes. Choanocytes are cells that have flagella, which beat to create a current push through the spongocoel. Syconoid- a tubular body whose wall is much thicker and highly folded into a series of incurrent canals that deliver water into radial canals lined with choanocytes. Leuconoid- the most complex level of organization, that allows an increase in body size. Clusters of flagellated chambers are filled from incurrent canals and discharge their water via excurrent canals into a central osculum. Return to original outline Return to phyla outline Class Calcarea Grantia Grantia 100x 100x Return to original outline Return to phyla outline Grantia spicules 100x Return to original outline Return to phyla outline Class Demospongiae Spongia Spongin Tissue 100x Return to original outline Return to phyla outline Representative Porifera Syconoid Grass Sponge Return to original outline Return to phyla outline Bath sponge- Leuconoid Return to original outline Return to phyla outline .

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Zoology Diversity of Invertebrates Structure
ZOOLOGY DIVERSITY OF INVERTEBRATES STRUCTURE OF OBELIA --------------------------------------------------------------------------- Introduction: Obelia is worldwide in distribution in the form of plant and is observed in white or light brown in colour in the form of fur in the seas and oceans. It is usually known as Sea-fur. Its name is derived from the Greek word called ‘obelias’,means loaf baked on a spit. • Phylum: Colenterata • Class: Hydrozoa • Order: Hydroida • Sub-order: Leptomedusae • Genus: Obelia • Species: geniculata As it is having three forms like polyp, medusa and blasto style, it is described as trimorphic hydrozoan. Among many species like O. geniculate, O. longissimi, O. bidentata, O. dichotoma. O. geniculate is the most common example studied. Habit and Habitat of Obelia: It is sedentary, marine colonial form present throughout the world on the surfaces of sea weeds, rocks, wooden piles, molluscan shells etc., in the shallow water up to 80-100 meters depth. It is observed in both sexual forms as hydroid colony and asexual form as medusa. Structure of Hydroid Colony: Hydroid colony of obelia is sensitive, transparent consists of horizontal hydrorhiza and vertical hydrocaulus. Hydrorhiza: Hydrorhiza is horizontal thread like root attached to the substratum. It is hollow tube like and gives of vertical branches called hydrocaulus. The tubular part of hydrorhiza are also called stolons. Hydrocaulus: Hydrocaulus are vertical branches arising from hydrorhiza for a length of 2-3 cms. These are also hollow with short lateral branches alternatively in cymose manner. Each alternate branch bears terminal polyp zooids. OBELIA COLONY Each ultimate branch terminates in nutritive zooids called hydranth and axils of the older polyps consists of reproductive zooids called blastostyles or gonangia, thus obelia colony is dimorphic and when gonangia produces saucer shaped buds as a result of asexual reproduction and develops into sexual zooids called medusae, obelia colony becomes trimorphic colony.
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Cnidaria: Hydrozoa) Associated to a Subtropical Sargassum Cymosum (Phaeophyta: Fucales) Bed
ZOOLOGIA 27 (6): 945–955, December, 2010 doi: 10.1590/S1984-46702010000600016 Seasonal variation of epiphytic hydroids (Cnidaria: Hydrozoa) associated to a subtropical Sargassum cymosum (Phaeophyta: Fucales) bed Amanda Ferreira Cunha1 & Giuliano Buzá Jacobucci2 1 Programa de Pós-Graduação em Zoologia, Instituto de Biociências, Universidade de São Paulo. Rua do Matão, Travessa 14, 101, Cidade Universitária, 05508-900 São Paulo, SP, Brazil. E-mail: [email protected] 2 Instituto de Biologia, Universidade Federal de Uberlândia. Rua Ceará, Campus Umuarama, 38402-400 Uberlândia, MG, Brazil. E-mail: [email protected] ABSTRACT. Hydroids are broadly reported in epiphytic associations from different localities showing marked seasonal cycles. Studies have shown that the factors behind these seasonal differences in hydroid richness and abundance may vary significantly according to the area of study. Seasonal differences in epiphytic hydroid cover and richness were evaluated in a Sargassum cymosum C. Agardh bed from Lázaro beach, at Ubatuba, Brazil. Significant seasonal differences were found in total hydroid cover, but not in species richness. Hydroid cover increased from March (early fall) to February (summer). Most of this pattern was caused by two of the most abundant species: Aglaophenia latecarinata Allman, 1877 and Orthopyxis sargassicola (Nutting, 1915). Hydroid richness seems to be related to S. cymosum size but not directly to its biomass. The seasonal differences in hydroid richness and algal cover are shown to be similar to other works in the study region and in the Mediterranean. Seasonal recruitment of hydroid species larvae may be responsible for their seasonal differences in algal cover, although other factors such as grazing activity of gammarid amphipods on S.
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Hydroids and Hydromedusae of Southern Chesapeake Bay
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Moodle Interface
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(Marlin) Review of Biodiversity for Marine Spatial Planning Within
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Hydroids (Cnidaria: Hydrozoa) from Japanese Tsunami Marine Debris Washing Ashore in the Northwestern United States
Aquatic Invasions (2014) Volume 9, Issue 4: 425–440 doi: http://dx.doi.org/10.3391/ai.2014.9.4.02 Open Access © 2014 The Author(s). Journal compilation © 2014 REABIC Research Article Hydroids (Cnidaria: Hydrozoa) from Japanese tsunami marine debris washing ashore in the northwestern United States Dale R. Calder1*, Henry H.C. Choong2,3, James T. Carlton4, John W. Chapman5, Jessica A. Miller5 and Jonathan Geller6 1,2Invertebrate Zoology Section, Department of Natural History, Royal Ontario Museum, 100 Queen’s Park, Toronto, Ontario, Canada, M5S 2C6 3Palaeobiology Section, Department of Natural History, Royal Ontario Museum,100 Queen’s Park, Toronto, Ontario, Canada, M5S 2C6 4Williams College-Mystic Seaport Maritime Studies Program, Mystic, Connecticut 06355, USA 5Department of Fisheries and Wildlife, Hatfield Marine Science Center, Oregon State University, 2030 SE Marine Science Drive, Newport, Oregon 97365, USA 6Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss Landing, California 95039, USA E-mail: [email protected] (DRC), [email protected] (HHCC), [email protected] (JTC), [email protected] (JWC), [email protected] (JAM), [email protected] (JG) *Corresponding author Received: 12 February 2014 / Accepted: 28 May 2014 / Published online: 4 August 2014 Handling editor: Melissa Frey Abstract Fourteen species of hydroids, including two anthoathecates and 12 leptothecates, are reported from the west coast of North America on debris from the tsunami that struck Japan on 11 March 2011. Six species were found on a dock that stranded at Agate Beach, Newport, Oregon, five from a boat at Gleneden Beach, Oregon, four from a dock in Olympic National Park, Washington, and two from a boat in Grays Harbor, Washington.
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Obelia Longissima Class: Hydrozoa, Hydroidolina
Phylum: Cnidaria Obelia longissima Class: Hydrozoa, Hydroidolina Order: Leptothecata A floating dock hydroid Family: Campanularidae Taxonomy: Obelia longissima was first de- about 0.5 mm in diameter; as they mature, scribed by Pallas in 1766. Synonymous in- they grow to 5 mm in diameter (Cornelius clude Campanularia flabellata, Gonothyraea 1975; Kozloff 1983). longissima, Laomeda flabellata, L. longissi- Color: Medusae are primarily clear. ma, O. flabellata, Sertularia longissima Their tentacle bases, mouths, gonads, and (WoRMS 2015). O. lucifera may also be a stomachs are sometimes yellow to brown, synonym (especially of the medusa form), while their gonads and mouths can be bright but further research is necessary to be sure. green (Puget Sound) (Arai and Brinckmann- There has been much debate over the spe- Voss 1980). cies identities within the genus Obelia Body: (Cornelius 1975; Arai and Brinckmann-Voss Bell: The bell is very thin and flat, with 1980). The taxonomy above was taken from a small stomach, no peduncle, and a rudi- the World Register of Marine Species mentary velum (Fig. 3). It is eversible (Arai (WoRMS 2015). In addition to confusion in and Brinckmann-Voss 1980). the lower taxonomy, the higher taxonomy Radial canals: There are four has undergone revision. The order Hydroida straight radial canals, each containing a glob- was determined to be synonymous with sub- ular gonad (Fig. 3). class Hydroidolina in 2004 (Schuchert Ring canal: The ring canal is 2015). narrow, with eight statocysts (balance struc- tures) (Arai and Brinckmann-Voss 1980) and Description no ocelli (Fig. 3). General Morphology: Obelia longissima Mouth: The mouth has 4 small, has two forms.
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Marine Invasive Species and Biodiversity of South Central Alaska
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PHYLUM 'Sea Walnuts'/'Comb Jellies' CTENOPHORA
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