Tunicata (Urochordata) Arquivo
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Eurochordata and Cephalochordata of Persian Gulf & Oman See
Subphylum Urochordata : Tunicates Class Ascidacea Class Larvacea Class Thaliacea Subphylum Cephalochordata : Amphioxus Phylum Chordata : 1 - Subphylum Urochordata 2 Subphylum Cephalochordata (Subphylum Urochordata : Tunicates ) Class Ascidiacea Class Larvacea Class Thaliacea (Subphylum Cephalochordata ) Class Ascidiacea Ascidia Kowalevsky Patricia Kott D. lane David George & Gordon Paterson Herdmania momus savigny Herdmania momus kiamanensis Didemnum candidum savigny Phallusia nigra savigny Styela canopus savigny Class Ascidiacea : Order : Aplousobranchia Family : Polyclinidae : Aplidium cf. rubripunctum C.Monniot & F. Monniot 1997 Polyclinum constellatum Savigny, 1816 Family Didemnidae Didemnum candidum Savigny, 1816 Didemnum cf. granulatum Tokioka, 1954 Didemnum obscurum F. Monniot 1969 Didemnum perlucidum F. Monniot, 1983 Didemnum sp. Didemnum yolky C.Monniot & F. Monniot 1997 Diplosoma listerianum Milne Edwards, 1841 Order : Phlebobranchia Family : Ascidiidae Ascidia sp. Phallusia julinea Sluiter, 1915 Phallusia nigra Savigny, 1816 Order : Stolidobranchia Family : Styelidae Botryllus gregalis Sluiter, 1898 Botryllus niger Herdman, 1886 Botryllus sp. Eusynstyela cf. hartmeyeri Michaelsen, 1904 Polyandrocarpa sp. Styela canopus Savigny, 1816 Symplegma bahraini C.Monniot & F. Monniot 1997 Symplegma brakenhielmi Michaelsen, 1904 Family pyuridae Herdmania momus Savigny, 1816 Pyura curvigona Tokioka, 1950 Pyurid sp. Class Larvacea Larva Seymour Sewell Phylum Chordata Subphylum Urochordata * Class Larvacea Order Copelata Family Fritillariidae -
The Origins of Chordate Larvae Donald I Williamson* Marine Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom
lopmen ve ta e l B Williamson, Cell Dev Biol 2012, 1:1 D io & l l o l g DOI: 10.4172/2168-9296.1000101 e y C Cell & Developmental Biology ISSN: 2168-9296 Research Article Open Access The Origins of Chordate Larvae Donald I Williamson* Marine Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom Abstract The larval transfer hypothesis states that larvae originated as adults in other taxa and their genomes were transferred by hybridization. It contests the view that larvae and corresponding adults evolved from common ancestors. The present paper reviews the life histories of chordates, and it interprets them in terms of the larval transfer hypothesis. It is the first paper to apply the hypothesis to craniates. I claim that the larvae of tunicates were acquired from adult larvaceans, the larvae of lampreys from adult cephalochordates, the larvae of lungfishes from adult craniate tadpoles, and the larvae of ray-finned fishes from other ray-finned fishes in different families. The occurrence of larvae in some fishes and their absence in others is correlated with reproductive behavior. Adult amphibians evolved from adult fishes, but larval amphibians did not evolve from either adult or larval fishes. I submit that [1] early amphibians had no larvae and that several families of urodeles and one subfamily of anurans have retained direct development, [2] the tadpole larvae of anurans and urodeles were acquired separately from different Mesozoic adult tadpoles, and [3] the post-tadpole larvae of salamanders were acquired from adults of other urodeles. Reptiles, birds and mammals probably evolved from amphibians that never acquired larvae. -
Towards an Understanding of Salp Swarm Dynamics. ICES CM 2002/N
CM 2002/ N:12 Towards an understanding of salp swarm dynamics by Patricia Kremer ABSTRACT Species of salps are characterized by intermittent blooms. Several studies have documented the importance of physical processes both in providing seed stocks of salps and creating an environment that is favorable for the rapid increase of salp populations. Although salps are typically oceanic, most observations of bloom dynamics have been made in more accessible inshore waters, so it is difficult to assess how frequent and widespread these swarms are. A review and comparison of existing data is helping to define geographic “hot spots” for salp blooms as well as the necessary physical and biological precursors. Although at this point, the review is far from complete, several generalities are emerging. The details of the physical forcing functions vary, but the overall physical regime seems to require a region of pulsed mixing of oceanic water that results in a relatively high standing stock of autotrophs. For a salp bloom to occur, there also needs to be an adequate seed population of salps and sufficient sustained primary production to support the biomass of the salp population as the bloom develops. As non-selective filter feeders, salps are able to remove a wide range of particulates from the water column, transforming the undigested portion into fast sinking feces. Therefore, when salps occur at high densities, the water is characterized by low abundance of other plankton, with obvious trophic implications. Patricia Kremer: Marine Sciences, University of Connecticut, Groton CT 06340-6097, USA [tel: +1 860 405 9140; fax: +1 860 405 9153; e-mail [email protected]] INTRODUCTION Salps are holoplanktonic grazers that have a life history, feeding biology, and population dynamics that contrasts sharply to copepods and other crustacean zooplankton (Madin and Deibel 1998). -
British Pelagic Tunicates, and the Choice of the 21 Species
REVIEWS BULLETIN OF MARINE SCIENCE, 34(1): 175-176, 1984 BRITISHPELAGICTUNICATES.J. H. Fraser. Synopses of the British Fauna (New Series) No. 20. Cambridge University Press. 1982. 57 pp., 23 figures, glossary and index. Soft cover. $12.95. The Synopses of the British Fauna, of which this is No. 20 in the series, are designed as field and laboratory pocketbooks for the use of amateur and profes- sional naturalists. They are intended to bridge the gap between popular field guides and professional treatises and monographs. This slim little volume on pelagic tunicates seems to serve this purpose admirably. Each of the 21 species of Appendicularians and Thaliaceans treated in this work is illustrated with line drawings showing the pertinent characters required for identification. Both aggregate and solitary forms are shown when such occur. Descriptions are brief but adequate and there are notes on distribution and abun- dance where pertinent. A very useful account of anatomical structures, life his- tories, ecology and distribution is given for each major group. There is also a glossary, index and a useful list of references. The introduction serves also to inform the reader on methods of capture, preservation and labeling. Complete keys are given for all levels from class to family, genus and species. The author is to be congratulated on the clarity of the couplet definitions. One may be puzzled, however, by the title, British Pelagic Tunicates, and the choice of the 21 species. Under the Appendicularia Fraser states that only Oi- kopleura dioica and Fritillaria borealis are found in British estuaries and inshore waters while Oikopleura labradoriensis is frequent in areas around the British Isles but is unlikely to be found in inshore waters. -
ETD Template
EXPLAINING EVOLUTIONARY INNOVATION AND NOVELTY: A HISTORICAL AND PHILOSOPHICAL STUDY OF BIOLOGICAL CONCEPTS by Alan Christopher Love BS in Biology, Massachusetts Institute of Technology, 1995 MA in Philosophy, University of Pittsburgh, 2002 MA in Biology, Indiana University, Bloomington, 2004 Submitted to the Graduate Faculty of Arts and Sciences in partial fulfillment of the requirements for the degree of Doctor of Philosophy in History and Philosophy of Science University of Pittsburgh 2005 UNIVERSITY OF PITTSBURGH FACULTY OF ARTS AND SCIENCES This dissertation was presented by Alan Christopher Love It was defended on June 22, 2005 and approved by Sandra D. Mitchell, PhD Professor of History and Philosophy of Science, University of Pittsburgh Robert C. Olby, PhD Professor of History and Philosophy of Science, University of Pittsburgh Rudolf A. Raff, PhD Professor of Biology, Indiana University, Bloomington Günter P. Wagner, PhD Professor of Ecology and Evolutionary Biology, Yale University James G. Lennox, PhD Dissertation Director Professor of History and Philosophy of Science, University of Pittsburgh ii Copyright by Alan Christopher Love 2005 iii EXPLAINING EVOLUTIONARY INNOVATION AND NOVELTY: A HISTORICAL AND PHILOSOPHICAL STUDY OF BIOLOGICAL CONCEPTS Alan Christopher Love, PhD University of Pittsburgh, 2005 Abstract Explaining evolutionary novelties (such as feathers or neural crest cells) is a central item on the research agenda of evolutionary developmental biology (Evo-devo). Proponents of Evo- devo have claimed that the origin of innovation and novelty constitute a distinct research problem, ignored by evolutionary theory during the latter half of the 20th century, and that Evo- devo as a synthesis of biological disciplines is in a unique position to address this problem. -
(Tunicata: Thaliacea: Salpida) in the Northeast Pacific
Revista Mexicana de Biodiversidad 85: 624-629, 2014 624 Hereu et al.- New record of Helicosalpa komaiiDOI: in 10.7550/rmb.36638 Northeast Pacific Research note Record of the rare oceanic salp Helicosalpa komaii (Tunicata: Thaliacea: Salpida) in the Northeast Pacific Registro de una especie oceánica rara de salpa Helicosalpa komaii (Tunicata: Thaliacea: Salpida) en el Pacífico nororiental Clara M. Hereu1 , Eduardo Suárez-Morales2 and Bertha E. Lavaniegos3 1Facultad de Ciencias, Universidad Autónoma de Baja California. Carretera Tijuana-Ensenada, Km 103, 22860 Ensenada, Baja California, Mexico. 2Departamento de Ecología y Sistemática Acuática, El Colegio de la Frontera Sur. Av. Centenario, Km 5.5, 77014 Chetumal, Quintana Roo, Mexico. 3Departamento de Oceanografía Biológica, Centro de Investigación y de Educación Superior de Ensenada. Carretera Tijuana-Ensenada Km 107, 22860 Ensenada, Baja California, Mexico. [email protected] Abstract. We report for the first time the presence of a rare salp Helicosalpa komaii (Ihle and Ihle-Landenberg, 1936) on the west coast of Baja California peninsula (26°52.7’ N, 117°09.2’ W). The single specimen recorded was a solitary zooid of 200 mm length and 90 ml of displacement volume. It was recognized by having a distinctive highly convoluted heart-shaped dorsal tubercle. The total number of muscle fibers in the solitary zooid (MI to MVII= 517) surpassed that of the other 2 known congeners supporting its identity as H. komaii. H. komaii increases to 29 the total number of salps species reported in coastal and oceanic waters off north-central Baja California (gamma diversity). We hypothesize that the presence of H. -
Phylum: Chordata
PHYLUM: CHORDATA Authors Shirley Parker-Nance1 and Lara Atkinson2 Citation Parker-Nance S. and Atkinson LJ. 2018. Phylum Chordata In: Atkinson LJ and Sink KJ (eds) Field Guide to the Ofshore Marine Invertebrates of South Africa, Malachite Marketing and Media, Pretoria, pp. 477-490. 1 South African Environmental Observation Network, Elwandle Node, Port Elizabeth 2 South African Environmental Observation Network, Egagasini Node, Cape Town 477 Phylum: CHORDATA Subphylum: Tunicata Sea squirts and salps Urochordates, commonly known as tunicates Class Thaliacea (Salps) or sea squirts, are a subphylum of the Chordata, In contrast with ascidians, salps are free-swimming which includes all animals with dorsal, hollow in the water column. These organisms also ilter nerve cords and notochords (including humans). microscopic particles using a pharyngeal mucous At some stage in their life, all chordates have slits net. They move using jet propulsion and often at the beginning of the digestive tract (pharyngeal form long chains by budding of new individuals or slits), a dorsal nerve cord, a notochord and a post- blastozooids (asexual reproduction). These colonies, anal tail. The adult form of Urochordates does not or an aggregation of zooids, will remain together have a notochord, nerve cord or tail and are sessile, while continuing feeding, swimming, reproducing ilter-feeding marine animals. They occur as either and growing. Salps can range in size from 15-190 mm solitary or colonial organisms that ilter plankton. in length and are often colourless. These organisms Seawater is drawn into the body through a branchial can be found in both warm and cold oceans, with a siphon, into a branchial sac where food particles total of 52 known species that include South Africa are removed and collected by a thin layer of mucus within their broad distribution. -
BLY 202 (Basic Chordates Zoology) Sub-Phylum Urochordata (Tunicata)
BLY 202 (Basic Chordates Zoology) Sub-Phylum Urochordata (Tunicata) Objectives are to; a) understand the characteristics of Urochordata b) have knowledge on Urochordata evolution c) understand the different classes and their physiology The urochordates (“tail-chordates”), more commonly called tunicates, include about 3000 species. Tunicates are also called sea squirts. They are found in all seas from near shoreline to great depths. Most are sessile as adults, although some are free living. The name “tunicate” is suggested by the usually tough, non-living tunic, or test that surrounds the animal and contains cellulose. As adults, tunicates are highly specialized chordates, for in most species only the larval form, which resembles a microscopic tadpole, bears all the chordate hallmarks. During adult metamorphosis, the notochord (which, in the larva, is restricted to the tail, hence the group name Urochordata) and the tail disappear altogether, while the dorsal nerve cord becomes reduced to a single ganglion. The body of the adult urochordates is unsegmented and lacks a tail. Nephrocytes are responsible for the excretion of urochordates. The asexual reproduction of urochordates occurs by budding. Urochordates are bisexual and the external fertilization is the mode of sexual reproduction. Urochordates have an unsegmented body. Urochordates are exclusively marine animal. The earliest probable species of tunicate appears in the fossil record in the early Cambrian period. Despite their simple appearance and very different adult form, their close relationship to the vertebrates is evidenced by the fact that during their mobile larval stage, they possess a notochord or stiffening rod and resemble a tadpole. Their name derives from their unique outer covering or "tunic", which is formed from proteins and carbohydrates, and acts as an exoskeleton. -
Reptile Pdf, Epub, Ebook
REPTILE PDF, EPUB, EBOOK Colin McCarthy | 72 pages | 18 Jun 2012 | DK Publishing | 9780756693046 | English | New York, United States Reptile PDF Book Test Your Vocabulary. View all Shop All Reptile Products. Goannas: The Biology of Varanid Lizards. It is generally accepted that this lower capacity is related to differences in the circulatory and respiratory systems. Taxonomically, Reptilia and Synapsida a group of mammal-like reptiles and their extinct relatives were sister groups that diverged from a common ancestor during the Middle Pennsylvanian Epoch approximately million to million years ago. Further information: Venom and Evolution of snake venom. Aquatic turtles have developed more permeable skin, and some species have modified their cloaca to increase the area for gas exchange. Lepidosauromorpha contained at least one major group of the Mesozoic sea reptiles: the mosasaurs , which lived during the Cretaceous period. Birds class Aves share a common ancestor with crocodiles in subclass Archosauria and are technically one lineage of reptiles, but they are treated separately see bird. This ensures that the embryo will not suffocate while it is hatching. Bibcode : Natur. Despite the early proposals for replacing the paraphyletic Reptilia with a monophyletic Sauropsida , which includes birds, that term was never adopted widely or, when it was, was not applied consistently. In particular, the Cretaceous—Paleogene extinction event wiped out the pterosaurs , plesiosaurs , ornithischians , and sauropods , alongside many species of theropods , crocodyliforms , and squamates e. Reptile Supply is dedicated to bringing you the highest quality live food and supplies for your reptiles, amphibians, inverts, and more! Watson observed that the first two groups diverged very early in reptilian history, so he divided Goodrich's Protosauria between them. -
On Some Pelagic Doliolid Tunicates (Thaliacea, Doliolida) Collected by a Submersible Off the Eastern North American Coast
BULLETIN OF MARINE SCIENCE, 72(3): 589–612, 2003 ON SOME PELAGIC DOLIOLID TUNICATES (THALIACEA, DOLIOLIDA) COLLECTED BY A SUBMERSIBLE OFF THE EASTERN NORTHAMERICAN COAST J. E. A. Godeaux and G. R. Harbison ABSTRACT Specimens of Doliolids collected from a submersible at several stations off the eastern coast of North America were examined. Four species were identified, of which three were described by Godeaux (1996). Of these, one belongs to the new genus, Paradoliopsis (Godeaux, 1996). It is proposed that the order Doliolida be divided into two suborders: the Doliolidina (animals with eight muscle bands), and the Doliopsidina (animals with five muscle bands). Each suborder is represented in our collection by two families. For the Doliolidina these families are the Doliolidae (Doliolinetta intermedia) and the Doliopsoididae (Doliopsoides atlanticum), and for the Doliopsidina the families are the Doliopsidae (Doliopsis bahamensis) and the Paradoliopsidae (Paradoliopsis harbisoni). The family Doliolidae is the best known group of the tunicate order Doliolida. The vertical distribution of members of this family has been well documented with the use of multiple opening and closing nets. The various stages of the complex life cycle of the different species of Doliolidae are located in the epipelagic and mesopelagic layers. They are mainly found at depths between 50–100 m, where they graze on small autotrophic algae (Weikert and Godeaux, unpubl.). Doliolids are so fragile that they are easily dam- aged, making their identification difficult. Identification and determination of the various stages in the life cycle is made even more difficult by the fact that several different spe- cies are often mixed together in a single net collection. -
Fiftee N Vertebrate Beginnings the Chordates
Hickman−Roberts−Larson: 15. Vertebrate Beginnings: Text © The McGraw−Hill Animal Diversity, Third The Chordates Companies, 2002 Edition 15 chapter •••••• fifteen Vertebrate Beginnings The Chordates It’s a Long Way from Amphioxus Along the more southern coasts of North America, half buried in sand on the seafloor,lives a small fishlike translucent animal quietly filtering organic particles from seawater.Inconspicuous, of no commercial value and largely unknown, this creature is nonetheless one of the famous animals of classical zoology.It is amphioxus, an animal that wonderfully exhibits the four distinctive hallmarks of the phylum Chordata—(1) dorsal, tubular nerve cord overlying (2) a supportive notochord, (3) pharyngeal slits for filter feeding, and (4) a postanal tail for propulsion—all wrapped up in one creature with textbook simplicity. Amphioxus is an animal that might have been designed by a zoologist for the classroom. During the nineteenth century,with inter- est in vertebrate ancestry running high, amphioxus was considered by many to resemble closely the direct ancestor of the vertebrates. Its exalted position was later acknowledged by Philip Pope in a poem sung to the tune of “Tipperary.”It ends with the refrain: It’s a long way from amphioxus It’s a long way to us, It’s a long way from amphioxus To the meanest human cuss. Well,it’s good-bye to fins and gill slits And it’s welcome lungs and hair, It’s a long, long way from amphioxus But we all came from there. But amphioxus’place in the sun was not to endure.For one thing,amphioxus lacks one of the most important of vertebrate charac- teristics,a distinct head with special sense organs and the equipment for shifting to an active predatory mode of life. -
DEIDRE MICHELLE GIBSON Feeding Growth and Reproduction Rates Of
DEIDRE MICHELLE GIBSON Feeding Growth and Reproduction Rates of the Doliolid Dolioletta gegenbauri Uljanin (Tunicata, Thaliacea) (Under the Direction of GUSTAV ADOLF PAFFENHÖFER) The objectives were to quantify feeding and growth of Dolioletta gegenbauri gonozooids and reproduction rates of Dolioletta gegenbauri phorozooids at 4 food concentrations, 3 food sizes, and 4 temperatures in order to determine their impact as grazers throughout the water column. Laboratory experiments were conducted at 16.5, 20, 23.5, and 26.5ºC quantifying removal of a 50:50 volumetric concentration of Thalassiosira weissflogii and Rhodomonas sp. at four different food concentrations of 7 20, 60, 160, and 390 µg C · l -1. Gonozooid clearance rates are similar at concentrations from 20 to 60 µg C · l -1, and decrease as the food concentrations increase to 160, and 390 µg C · l –1. The ingestion rates increase over a range of phytoplankton concentrations from 20 to 160 µg C · l -1, then decrease when abnormally high concentrations of 390 µg C · l -1 are offered. Clearance and ingestion rates increase as temperature increases from 16.5 to 26.5º C. The exponential growth rates range from k = 0.2 - 0.7 with the lowest rates occurring at the highest food concentration. Growth rates increase with increasing temperature from K = 0.1-0.3/day at 16.5º C to 0.45-0.7 at 26.5º C. Phorozooid release rates increased at 20 oC as concentration increases from 7 to 160 µg C/l. Release rates remained similar as the temperature increased from 16.5 to 26.5 oC at a phytoplankton concentration of 60 µg C/l.