A blog by my comrade Omar, who takes part in anarchist movement here in Auckland, NZ. An anarchist's view on New Zealand and the world - in English.
20 most recent
Sun, Sep. 9th, 2007, 11:56 pm
Comrade Omar's blog.
http://lifeduringcapitalism.blogspot.co
A blog by my comrade Omar, who takes part in anarchist movement here in Auckland, NZ. An anarchist's view on New Zealand and the world - in English.
A blog by my comrade Omar, who takes part in anarchist movement here in Auckland, NZ. An anarchist's view on New Zealand and the world - in English.
Fri, Aug. 10th, 2007, 12:57 pm
О политических репрессиях в Венесуэлле.
По рассылке пришло письмо солидарности с венесуэлльскими товарищами из анархических и прочих социальных движений. Там содержится информация о ситуации в одном из самых популярных государственных режимов мира из первых уст. Как мы видим, не так уж я был неправ, когда говорил, что Чавес и Путин - близнецы-братья. Недаром у них такие хорошие отношения...
Manifesto of solidarity with Venezuelan anarchists and social movements
* The newspaper Tierra y Libertad, mouthpiece of the Iberian Anarchist Federation, published in edition 227 of June 2007 this manifesto of the International of Anarchist Federations (IAF-IFA; www.iaf-ifa.org) in support of those who in Venezuela today confront the bureaucratic capitalist project of the Chavez government as well as their social democrat and right wing opponents.
In the first three months of 2007, 23 popular demonstrations were repressed by the Venezuelan government and 99 activists were detained. This fact speaks of the growing unease as well as the criminalization of social struggle in this Latin-American country, in a reality masked by the propaganda and mystification of a regime that paints itself as the vanguard of ‘21st Century socialism’ with the support of different groupings and persons associated with the authoritarian left throughout the world.
However, those who are concerned with the real situation of the oppressed and exploited in Venezuela know the inconsistencies and contradictions of the populist government led by the militarist Hugo Chavez. Far from structurally advancing the reduction of inequalities and the increase of possibilities of social development, the government in power in Caracas continues to maintain one of the most unjust systems of distribution of wealth in the continent, further deepening the role assigned to the country by economic globalization as a secure and trustworthy provider of energy to the global market, with trans-national oil corporations as pampered partners and principal beneficiaries of the actions of the Venezuelan state. After eight and a half years of a government relying on high oil prices with the highest financial income in national history, the social results of Chavez’s politics are mediocre, the most notable being the apparition of a new parasitic bourgeoisie of the client state, the ‘bolivarian bourgeoisie’.
According to recent government reports and statistics, over 5 million workers, 46.5% of the labour force remain in the informal sector of the economy, 43% of workers receive a salary under the legal minimum wage, a little less than 200 dollars per month, 2.5 million people lack suitable housing, 18% of the population suffer malnutrition, the network of public hospitals displays needs and limitations of every type, 90% of the indigenous population live in poverty, more than 400 people die violently each year in prison and there is an average of 15 people assassinated every month by repressive organs of the state.
The Venezuelan government has maintained over the last five years an inter-class dispute with certain traditional sectors of the local bourgeoisie which, in the midst of a strong political-electoral polarization, has allowed the division, immobilization, and recuperation of the country’s social movements. Any critic of the corrupt, inefficient and wasteful official bureaucracy would immediately qualify it as being ‘at the service of imperialism’, and with the excuse of confronting possible ‘coup’s and ‘reactionary provocations’, they have announced diverse laws that penalize with greater vigour street actions and strikes in the basic state industries. These are part of legal mechanisms that since 2006 have been used against popular mobilizations which, trying to recuperate their own demands, demonstrate every week for the right to personal security, decent housing, work and decent working conditions. The response of the government has been with tear gas grenades, gunshots and arrests.
Faced with the deceitful polarization experienced in this country, and specifically as a response to the presidential mandate to dissolve previously existing parties and groupings in order to integrate them in to the single party of Chavism, with the acronym PSUV, diverse Venezuelan organisations are trying to create autonomous spaces for the social movements. Amongst these are the efforts of the anarchists who from separate initiatives, such as the publication El Libertario (www.nodo50.org/ellibertario) are building an alternative that is as removed from the social democrat and right wing opposition as it is from the capitalism of the Bolivarian state. This effort by the anarchists to construct alternatives and routes that are consistently autonomous implies risks: El Libertario, for example, must face a systematic campaign of recriminations and disrepute from fictitious groups paid for by the state, thus there is a growing harassment of anti-authoritarian activism.
This manifesto wishes to remind our libertarian brothers and sisters inside Venezuela, as well as the various grass roots autonomous organisations that they have our appreciation, support and solidarity. Our anarchist organisations and initiatives will denounce, in every way they can, the incoherence and demagoguery hidden behind the alias of the ‘bolivarian revolution’, activating the necessary support mechanisms in response to every government attack against the concrete aspirations of social justice and liberty of the Venezuelan people.
Manifesto of solidarity with Venezuelan anarchists and social movements
* The newspaper Tierra y Libertad, mouthpiece of the Iberian Anarchist Federation, published in edition 227 of June 2007 this manifesto of the International of Anarchist Federations (IAF-IFA; www.iaf-ifa.org) in support of those who in Venezuela today confront the bureaucratic capitalist project of the Chavez government as well as their social democrat and right wing opponents.
In the first three months of 2007, 23 popular demonstrations were repressed by the Venezuelan government and 99 activists were detained. This fact speaks of the growing unease as well as the criminalization of social struggle in this Latin-American country, in a reality masked by the propaganda and mystification of a regime that paints itself as the vanguard of ‘21st Century socialism’ with the support of different groupings and persons associated with the authoritarian left throughout the world.
However, those who are concerned with the real situation of the oppressed and exploited in Venezuela know the inconsistencies and contradictions of the populist government led by the militarist Hugo Chavez. Far from structurally advancing the reduction of inequalities and the increase of possibilities of social development, the government in power in Caracas continues to maintain one of the most unjust systems of distribution of wealth in the continent, further deepening the role assigned to the country by economic globalization as a secure and trustworthy provider of energy to the global market, with trans-national oil corporations as pampered partners and principal beneficiaries of the actions of the Venezuelan state. After eight and a half years of a government relying on high oil prices with the highest financial income in national history, the social results of Chavez’s politics are mediocre, the most notable being the apparition of a new parasitic bourgeoisie of the client state, the ‘bolivarian bourgeoisie’.
According to recent government reports and statistics, over 5 million workers, 46.5% of the labour force remain in the informal sector of the economy, 43% of workers receive a salary under the legal minimum wage, a little less than 200 dollars per month, 2.5 million people lack suitable housing, 18% of the population suffer malnutrition, the network of public hospitals displays needs and limitations of every type, 90% of the indigenous population live in poverty, more than 400 people die violently each year in prison and there is an average of 15 people assassinated every month by repressive organs of the state.
The Venezuelan government has maintained over the last five years an inter-class dispute with certain traditional sectors of the local bourgeoisie which, in the midst of a strong political-electoral polarization, has allowed the division, immobilization, and recuperation of the country’s social movements. Any critic of the corrupt, inefficient and wasteful official bureaucracy would immediately qualify it as being ‘at the service of imperialism’, and with the excuse of confronting possible ‘coup’s and ‘reactionary provocations’, they have announced diverse laws that penalize with greater vigour street actions and strikes in the basic state industries. These are part of legal mechanisms that since 2006 have been used against popular mobilizations which, trying to recuperate their own demands, demonstrate every week for the right to personal security, decent housing, work and decent working conditions. The response of the government has been with tear gas grenades, gunshots and arrests.
Faced with the deceitful polarization experienced in this country, and specifically as a response to the presidential mandate to dissolve previously existing parties and groupings in order to integrate them in to the single party of Chavism, with the acronym PSUV, diverse Venezuelan organisations are trying to create autonomous spaces for the social movements. Amongst these are the efforts of the anarchists who from separate initiatives, such as the publication El Libertario (www.nodo50.org/ellibertario) are building an alternative that is as removed from the social democrat and right wing opposition as it is from the capitalism of the Bolivarian state. This effort by the anarchists to construct alternatives and routes that are consistently autonomous implies risks: El Libertario, for example, must face a systematic campaign of recriminations and disrepute from fictitious groups paid for by the state, thus there is a growing harassment of anti-authoritarian activism.
This manifesto wishes to remind our libertarian brothers and sisters inside Venezuela, as well as the various grass roots autonomous organisations that they have our appreciation, support and solidarity. Our anarchist organisations and initiatives will denounce, in every way they can, the incoherence and demagoguery hidden behind the alias of the ‘bolivarian revolution’, activating the necessary support mechanisms in response to every government attack against the concrete aspirations of social justice and liberty of the Venezuelan people.
Sun, Jul. 29th, 2007, 04:35 pm
Refuting the deafs: Chavizm and Anarchism in Venesuella.
Выкладываю довольно старый (майский) текст из El Libetario в английском переводе - про Чавеса и ситуацию в Венесуэлле. Текст пришёл мне по внутренней рассылке IFA. Довольно интересный взгляд из стана анархистов - и ушат холодной воды на горячие головы чавесопоклонников %)
( Букав много, и все нерусские )
( Букав много, и все нерусские )
Mon, Jun. 25th, 2007, 06:33 pm
Exceptionally cool.
Wed, Jun. 20th, 2007, 07:30 pm
Translation.
by ![[info]](http://lj.rossia.org/img/userinfo-lj.gif)
ramzi-binalshib@lj, с изменениями
You have your opinion and you think it's right. If I try to argue it, you'll shut me up, because you kept to your opinion all your life, and now, even if something doesn't seem quite right about it, you just turn your blind eye to it or try to find an excuse, but not to think it over. I wouldn't push you to change your views, I'm not trying to make you see me or hear me. But try to remember, where did you get your ideas from. TV? School? Parents? Friends? Journals and newspapers? "Moral authorities"? Say it for yourself.
My point of view is one from fate, search for justice, fight for freedom, long memory and support of my comrades. And I think it's right.
I don't fear the rich, because I'm not for sale.
I don't fear them who paints all the world brown, because my color cannot be changed.
I don't fear ones in power, because it's them who should be afraid.
I don't fear ones who can kill me, because I am not alone and they can't kill us all.
I don't fear, because in every minute we're getting louder.
Just because we simply do not fear.
ramzi-binalshib@lj, с изменениямиYou have your opinion and you think it's right. If I try to argue it, you'll shut me up, because you kept to your opinion all your life, and now, even if something doesn't seem quite right about it, you just turn your blind eye to it or try to find an excuse, but not to think it over. I wouldn't push you to change your views, I'm not trying to make you see me or hear me. But try to remember, where did you get your ideas from. TV? School? Parents? Friends? Journals and newspapers? "Moral authorities"? Say it for yourself.
My point of view is one from fate, search for justice, fight for freedom, long memory and support of my comrades. And I think it's right.
I don't fear the rich, because I'm not for sale.
I don't fear them who paints all the world brown, because my color cannot be changed.
I don't fear ones in power, because it's them who should be afraid.
I don't fear ones who can kill me, because I am not alone and they can't kill us all.
I don't fear, because in every minute we're getting louder.
Just because we simply do not fear.
Mon, Jun. 18th, 2007, 02:36 pm
Тайна имени.
Понравилось высказывание тут одного товарища про Hillary Duff:
Of course she's a whore! What else could she possibly be with a name like that? Imagine people calling 'miss Duff' all the time, wouldn't it eventually make you a whore too?
Of course she's a whore! What else could she possibly be with a name like that? Imagine people calling 'miss Duff' all the time, wouldn't it eventually make you a whore too?
Fri, Jun. 15th, 2007, 10:15 pm
Interview about Russian @-movement.
The Auckland anarchist zine "A Space Inside" made by anarchist collective of the same name is finally out. Its contents can be read on the "A Space Inside" site.
Among other interesting stuff, the zine contains my interview about the Movement in russia. I answered several questions of my comrade, let's call him Omar, via email.
Here it is. I ask all the russian comrades to check if I put all the facts right.
( The interview text )
Among other interesting stuff, the zine contains my interview about the Movement in russia. I answered several questions of my comrade, let's call him Omar, via email.
Here it is. I ask all the russian comrades to check if I put all the facts right.
( The interview text )
Wed, Jun. 13th, 2007, 02:36 am
Пост про нациков.
Нашёл в международной англоязычной коммуне ![[info]](http://lj.rossia.org/img/community-lj.gif)
anarchists@lj пост, посвящённый русским нацикам. Пытаюсь убедить зарубежных товарищей, что это не просто тупоголовые малолетки, а серьёзная мразь, представляющая опасность для всего мира.
Вот: http://community.livejournal.com/anarch
Кто владеет буржуйской мовой, подключайтесь к дискуссии.
anarchists@lj пост, посвящённый русским нацикам. Пытаюсь убедить зарубежных товарищей, что это не просто тупоголовые малолетки, а серьёзная мразь, представляющая опасность для всего мира. Вот: http://community.livejournal.com/anarch
Кто владеет буржуйской мовой, подключайтесь к дискуссии.
Sat, Jun. 2nd, 2007, 08:47 pm
В порядке подготовки к экзамену.
Систематика царства животных - немного не так, как нас учили в питерском Универе. Вероятно, разные школы, плюс кое-что могло измениться со временем... Естественно, не все типы, а только которые мы проходили, с небольшой характеристикой каждого типа.
Не биологам и/или не знающим английского может быть неинтересно, так что ныкаю под кат.
Буду периодически обновлять и писать характеристику про каждый тип отдельным постом. Чтобы не забивать френленты неинересующимся, буду эти посты датировать 1997 годом и ставить ссылку из этого поста.
( Read more... )
Не биологам и/или не знающим английского может быть неинтересно, так что ныкаю под кат.
Буду периодически обновлять и писать характеристику про каждый тип отдельным постом. Чтобы не забивать френленты неинересующимся, буду эти посты датировать 1997 годом и ставить ссылку из этого поста.
( Read more... )
Wed, Jun. 4th, 1997, 06:09 pm
phylum Rotifera.
Eumetazoa
Bilateria
Protostomata
Lophotrochozoa
Pseudocoelomata
Defining Characteristics: Pharynx highly muscular and contain jaws for grasping, crushing or grinding prey or attaching to host; toes with adgesive glands.
Name from Latin rota - wheel and ferare - to bear. Name derived from characteristic wheel-shaped ciliated organ - the corona on top of the animal. Cilia beat a wave that passes around the periphery metachronally.
About 2000 species. Small (0,1 to 1mm), mostly freshwater, 5-10% marine. Some live interstitially between sand grains.
Pseudocoelomate. Eutelic - fixed number of nuclei in every organ and organ system. Syncitial epidermis. Non-chitinous intracellular "cuticle" that's never moulted.
Bodu divided in: head (corona, mouth, sensory lorgans and brain); trunk (elongate and sac-like, with mastax, gut and anus at posterior); foot with 1 to 4 toes, secretind mucus used to attach to substrate.
Mouth leads to muscular phaynx that containt the mastax used to crush or tear food, then to stomach, intestine and anus. Most omnivores, eat algae, zooplancton, detritus etc.
2 coiled tubular protonephridia each with several flame-cells.
Circular and lonitudinal muscles, but no sheets or layers of body wall muscles. Many free-livong rotifiers can move by looping (corona acts as suction cup). Most sessile as adults, attach to substrate with pedal gland secretins; some secrete protective tubes, sometimes with grains of sand and faeces.
Asexual reproduction by parthenogenesis (development of unfertilized eggs).
classes:
Class Seisonidea.
2 species; ectoparasites of marine crustaceans; corona reduced in size. No asexual reproducrion; sexes separate; internal feritilization by copulation or hydroponic inpregnation of sperm into the pseudocoel.
class Bdelloidea.
~350 species, all free-living and mobile. Live in damp soil, wet moss, hot springs, Antarctic lakes, few marine species. Omnivorous suspension-feeders; well-developed bilobial corona. Reproduction believed to be only by parthenogenesis since males have never been found. Some species shown to enter cryptobiosis in unpleasant environmental conditions. Can withstand environmental extremes for up to 20 years.
class Monogonata.
about 1400 species; free-living or sessile; some use corona to feed, others have spines used to capture prey. Cuticle is thick and rigid - s.c. lorica.
Unique reproductive pattern:
Typically reproduce by parthenogenesis: females procuce amictic eggs by mitosis. Under some conditions, however, they produce mictic eggs by meiosis. They, if not fertilized, develop into males (small, non-feeding, fast swimmers, live only a few days). Fertilized eggs form mictic "winter eggs", highly resistant to unfavourable conditions. Can survive up to 40 years before emerging.
Bilateria
Protostomata
Lophotrochozoa
Pseudocoelomata
Defining Characteristics: Pharynx highly muscular and contain jaws for grasping, crushing or grinding prey or attaching to host; toes with adgesive glands.
Name from Latin rota - wheel and ferare - to bear. Name derived from characteristic wheel-shaped ciliated organ - the corona on top of the animal. Cilia beat a wave that passes around the periphery metachronally.
About 2000 species. Small (0,1 to 1mm), mostly freshwater, 5-10% marine. Some live interstitially between sand grains.
Pseudocoelomate. Eutelic - fixed number of nuclei in every organ and organ system. Syncitial epidermis. Non-chitinous intracellular "cuticle" that's never moulted.
Bodu divided in: head (corona, mouth, sensory lorgans and brain); trunk (elongate and sac-like, with mastax, gut and anus at posterior); foot with 1 to 4 toes, secretind mucus used to attach to substrate.
Mouth leads to muscular phaynx that containt the mastax used to crush or tear food, then to stomach, intestine and anus. Most omnivores, eat algae, zooplancton, detritus etc.
2 coiled tubular protonephridia each with several flame-cells.
Circular and lonitudinal muscles, but no sheets or layers of body wall muscles. Many free-livong rotifiers can move by looping (corona acts as suction cup). Most sessile as adults, attach to substrate with pedal gland secretins; some secrete protective tubes, sometimes with grains of sand and faeces.
Asexual reproduction by parthenogenesis (development of unfertilized eggs).
classes:
Class Seisonidea.
2 species; ectoparasites of marine crustaceans; corona reduced in size. No asexual reproducrion; sexes separate; internal feritilization by copulation or hydroponic inpregnation of sperm into the pseudocoel.
class Bdelloidea.
~350 species, all free-living and mobile. Live in damp soil, wet moss, hot springs, Antarctic lakes, few marine species. Omnivorous suspension-feeders; well-developed bilobial corona. Reproduction believed to be only by parthenogenesis since males have never been found. Some species shown to enter cryptobiosis in unpleasant environmental conditions. Can withstand environmental extremes for up to 20 years.
class Monogonata.
about 1400 species; free-living or sessile; some use corona to feed, others have spines used to capture prey. Cuticle is thick and rigid - s.c. lorica.
Unique reproductive pattern:
Typically reproduce by parthenogenesis: females procuce amictic eggs by mitosis. Under some conditions, however, they produce mictic eggs by meiosis. They, if not fertilized, develop into males (small, non-feeding, fast swimmers, live only a few days). Fertilized eggs form mictic "winter eggs", highly resistant to unfavourable conditions. Can survive up to 40 years before emerging.
Wed, Jun. 4th, 1997, 03:33 pm
phylum Bryozoa.
Common name - moss animals.
Synonims: Ectoprocta - emphasis that anus lies outside the ring of tentacles; Polyzoa - refers to coloial nature of all Bryozoans.
All colonial, but huge differences in morphology - erect or branching, flat or encrusting... Colonies formed by asexual reproduction of a single ancestrula larva. Zooids minute (<1mm), up tp 2 million per colony (colonies can be several meters large). About 6000 species (largest and most common lophophorate phyla). All aquatic, most marine. All but 1 Antarctic species attach to substrate.
All bryozoans secret house around the body. Contents of the house are called polypide: lophophore, gut, nerve ganglia, most of musculature. House itself plus body wall that secretes it - cystid. Secreted non-living part of house - zooecium.
During the lifetime, a whole polypide periodiaclly degenerates to a dark-pigmented, spherical mass called brown body. In most species new polypide is prodused from the cystid. Brown body is then excreted through the anus. This system may be used for bypassing unfavorable conditions or for waste ecxretion (no nephridia).
Septum dividing metacoel from mesocoel is very incomplete; thus coelomic fluid from body cavity continues in lophophore and tentacle cavities. Some species can retract lophophore into zooecium. Many species form funicular cords - tissue connections between zooids. Function unknown.
U-shaped gut. Mouth, muscular pharynx with ciliated rejection groove, short oesophagus, stomach, intestine, anus.
No specialized respiratory, circulatory or excretory systems (probably due to small size).
Colonies always hermaphroditic, but individual zooids can be of single sex. Gametes arise from germinal tissue in the metacoel peritoneum. A few species have external fertilisation, but most retain the ova at least for early larval stages.
3 classes:
class Phylactolaemata.
About 50 species. Only freshwater. Zooids monomorphic. Covering chitinous or gelatinous. Diameter of single colony can be >50cm. Colonies on submerged solid surfaces - shell, rocks, leaves etc.
U-shaped lophophore and epistome as in Phoronids. body wall contains both circular and longitudinal muscles. Coelomic cavity common for all zooids (=funiculus). Lophophore retractable.
Each zooid produce statoblasts. Statoblast consists of cell mass within bivalve protective shell of species-specific morphology. They are released when zooid degenerates at autumn. When environmental conditions improve following spring, valves open and polipide emerges. Two kinds of statoblasts:
Sessoblasts - cemented to substrate.
Floatoblasts - buoyant by gas-filled cells and dispersed by water, wind, animals etc.
class Gymnolamata.
Includes most extant species. Primarily marine, broad range of morphologic and functional diversity.
Zooids morphologically distinct. No common funiculus, though coelomic fluids can be exchanged through pore plates.
Circular lophophore.
Coloniec cna be polymorphic and consist of autozooids (feeding and reproduction) and heterozooids (non-feeding, non-reproductive, specialized for particular functions). E.g.: stolons; vibracula - modified operculum to prevent larval settlement and clean debris; avicularia - "biting" zooids, used to discourage, mutiliate or kill potential predators.
2 orders:
Order Ctenostomata (Greek κτένο - comb).
Flexible, chitinous zooecium; lophophore protraction as in phylactolaemates - by increasing hydrostatic pressure.
Order Cheilostomata (Greek χέιλο - lip).
Zooecium is calcified in various degrees. Many species have operculum that allows polypide to be completely withdrawn into cystid.
class Stenolaemata.
1 order Cyclostomata.
All marine. Always tubular and erect. Zooecia completely calcified. Non-muscular cystid; lophophore withdrawn with retractor muscles.
Synonims: Ectoprocta - emphasis that anus lies outside the ring of tentacles; Polyzoa - refers to coloial nature of all Bryozoans.
All colonial, but huge differences in morphology - erect or branching, flat or encrusting... Colonies formed by asexual reproduction of a single ancestrula larva. Zooids minute (<1mm), up tp 2 million per colony (colonies can be several meters large). About 6000 species (largest and most common lophophorate phyla). All aquatic, most marine. All but 1 Antarctic species attach to substrate.
All bryozoans secret house around the body. Contents of the house are called polypide: lophophore, gut, nerve ganglia, most of musculature. House itself plus body wall that secretes it - cystid. Secreted non-living part of house - zooecium.
During the lifetime, a whole polypide periodiaclly degenerates to a dark-pigmented, spherical mass called brown body. In most species new polypide is prodused from the cystid. Brown body is then excreted through the anus. This system may be used for bypassing unfavorable conditions or for waste ecxretion (no nephridia).
Septum dividing metacoel from mesocoel is very incomplete; thus coelomic fluid from body cavity continues in lophophore and tentacle cavities. Some species can retract lophophore into zooecium. Many species form funicular cords - tissue connections between zooids. Function unknown.
U-shaped gut. Mouth, muscular pharynx with ciliated rejection groove, short oesophagus, stomach, intestine, anus.
No specialized respiratory, circulatory or excretory systems (probably due to small size).
Colonies always hermaphroditic, but individual zooids can be of single sex. Gametes arise from germinal tissue in the metacoel peritoneum. A few species have external fertilisation, but most retain the ova at least for early larval stages.
3 classes:
class Phylactolaemata.
About 50 species. Only freshwater. Zooids monomorphic. Covering chitinous or gelatinous. Diameter of single colony can be >50cm. Colonies on submerged solid surfaces - shell, rocks, leaves etc.
U-shaped lophophore and epistome as in Phoronids. body wall contains both circular and longitudinal muscles. Coelomic cavity common for all zooids (=funiculus). Lophophore retractable.
Each zooid produce statoblasts. Statoblast consists of cell mass within bivalve protective shell of species-specific morphology. They are released when zooid degenerates at autumn. When environmental conditions improve following spring, valves open and polipide emerges. Two kinds of statoblasts:
Sessoblasts - cemented to substrate.
Floatoblasts - buoyant by gas-filled cells and dispersed by water, wind, animals etc.
class Gymnolamata.
Includes most extant species. Primarily marine, broad range of morphologic and functional diversity.
Zooids morphologically distinct. No common funiculus, though coelomic fluids can be exchanged through pore plates.
Circular lophophore.
Coloniec cna be polymorphic and consist of autozooids (feeding and reproduction) and heterozooids (non-feeding, non-reproductive, specialized for particular functions). E.g.: stolons; vibracula - modified operculum to prevent larval settlement and clean debris; avicularia - "biting" zooids, used to discourage, mutiliate or kill potential predators.
2 orders:
Order Ctenostomata (Greek κτένο - comb).
Flexible, chitinous zooecium; lophophore protraction as in phylactolaemates - by increasing hydrostatic pressure.
Order Cheilostomata (Greek χέιλο - lip).
Zooecium is calcified in various degrees. Many species have operculum that allows polypide to be completely withdrawn into cystid.
class Stenolaemata.
1 order Cyclostomata.
All marine. Always tubular and erect. Zooecia completely calcified. Non-muscular cystid; lophophore withdrawn with retractor muscles.
Wed, Jun. 4th, 1997, 03:22 pm
phylum Cycliophora
Phylum discovered in 1995. Only one species known - Symbion pandora. 0,35 mm in length, lives on the lips of Norway lobster Nephrops norvegica. Feeding stage with a dwarf male; anus just behind a ciliated mouth ring. Protonephridia. Life cycle unclear, trochophore-like larva found. Inner budding and larval brooding similar to Bryozoans and Entoprocts. 18s rDNA analysis sugests closer relation to Rotifers than Bryozoans.
Wed, Jun. 4th, 1997, 02:47 pm
phylum Entoprocta.
150 species, most marine. Suspension-feeding, benthic, solitary or colonial. Collect food particles using lophophore-similar organ, having numerous ciliated tentacles; but anus lies within circle of tentacles => not a Lophophorate. Pattern of water flow opposite to that shown in Lophophorates.
Small, usually <1-2mm; no blood vessels; U-shaped digestive tract.
Have spiral, determinate cleavage. Larva protostome-like trochophore. Have a small body cavity, but unclear how it forms. Acoelomate or pseudocoelomate?
Some species form colonies by asexual reproduction, but colonies never polymorphic. All zooids capable of feeding and reproduction.
All species are hermaphrodites.
Small, usually <1-2mm; no blood vessels; U-shaped digestive tract.
Have spiral, determinate cleavage. Larva protostome-like trochophore. Have a small body cavity, but unclear how it forms. Acoelomate or pseudocoelomate?
Some species form colonies by asexual reproduction, but colonies never polymorphic. All zooids capable of feeding and reproduction.
All species are hermaphrodites.
Tue, Jun. 3rd, 1997, 09:28 pm
phylum Brachiopoda.
Common name - lamp shells.
Can be thought of as a Phoronid with hard shells.
All marine, found from intertidial level to the deep sea. Only about 350 living species; more then 30000 found as fossils.
Resemble bivalvic molluscs, have a mantle and bivalve shell - but this similarity is superficial. Valves dorsoventral (lateral in molluscs). Dorsal and ventral valves are morphologically different. Ventral - pedicle valve, dorsal - brachial valve with lophophore. Shells are calcite or chitinophosphate (aragonite in molluscs).
from 1mm to 9cm in longest shell dimension. Sit attached to substrate, filter-feeding with lophophore.
U-shaped digestive system: mouth => oesophagus => stomach => intestine.
No specialized respiratory organs - gas exchange through lophophore and mantle. Open, very reduced circulatory system. Contracticle heart lies just above gut; after leaving dorsal vessel, blood moves in system of interconnected blood sinuses. Blood contains no oxygen-binding pigments, but haemoerythrin found in coelomic fluid (for nutrient distribution?)
Excretion by 1 or 2 pairs of metanephridia.
No asexual reproduction; sexes separate. Gametes develop from gonadal tissue and excreted to metacoel and out through nephridia. In most cases fertilisation external; some species known to brood embryos until larval stage and fertilize internally.
Deuterostomous development - radial cleavage, secondary mouth formation, enterocoely. Special free-swimming larval form - "lobate larva".
2 classes:
Articulata - shells attach by tooth and socket hinge, live attached by substrate. (about 300 species). Pedicle may be short with no muscle or muscular. A few species have no pedicle and attach by ventral valve.
Shell opened by deductor muscle, the hinge prevents large gap. Closed by adductor muscle.
Intestine ends blindly (secondary loss of anus).
Inarticulata - shells basically unattached and only held together by muscles. Live in soft substrate. Long, muscular pedicle used to pull animal down burrough. Some active, moving by setae and pedicles.
No deductor muscles. Gape by retracting the body, increasing pressure of coelomic fluid, forcing valves apart. Intestine ends with rectum and anus. Opens medially or to the right side of mantle cavity.
Can be thought of as a Phoronid with hard shells.
All marine, found from intertidial level to the deep sea. Only about 350 living species; more then 30000 found as fossils.
Resemble bivalvic molluscs, have a mantle and bivalve shell - but this similarity is superficial. Valves dorsoventral (lateral in molluscs). Dorsal and ventral valves are morphologically different. Ventral - pedicle valve, dorsal - brachial valve with lophophore. Shells are calcite or chitinophosphate (aragonite in molluscs).
from 1mm to 9cm in longest shell dimension. Sit attached to substrate, filter-feeding with lophophore.
U-shaped digestive system: mouth => oesophagus => stomach => intestine.
No specialized respiratory organs - gas exchange through lophophore and mantle. Open, very reduced circulatory system. Contracticle heart lies just above gut; after leaving dorsal vessel, blood moves in system of interconnected blood sinuses. Blood contains no oxygen-binding pigments, but haemoerythrin found in coelomic fluid (for nutrient distribution?)
Excretion by 1 or 2 pairs of metanephridia.
No asexual reproduction; sexes separate. Gametes develop from gonadal tissue and excreted to metacoel and out through nephridia. In most cases fertilisation external; some species known to brood embryos until larval stage and fertilize internally.
Deuterostomous development - radial cleavage, secondary mouth formation, enterocoely. Special free-swimming larval form - "lobate larva".
2 classes:
Articulata - shells attach by tooth and socket hinge, live attached by substrate. (about 300 species). Pedicle may be short with no muscle or muscular. A few species have no pedicle and attach by ventral valve.
Shell opened by deductor muscle, the hinge prevents large gap. Closed by adductor muscle.
Intestine ends blindly (secondary loss of anus).
Inarticulata - shells basically unattached and only held together by muscles. Live in soft substrate. Long, muscular pedicle used to pull animal down burrough. Some active, moving by setae and pedicles.
No deductor muscles. Gape by retracting the body, increasing pressure of coelomic fluid, forcing valves apart. Intestine ends with rectum and anus. Opens medially or to the right side of mantle cavity.
Tue, Jun. 3rd, 1997, 05:36 pm
phylum Phoronida.
Only 12 species in 2 genera - Phoronis and Phoronopsis.
All marine and live in chitinous tubes implanted in muddy or sandy sediments or attached to solid surfaces; sessile, but can move within theit tubes. Have giant nerve fibre that allows the animal to withdraw rapidly. Found from intertidal to 400 m. ~12cm long, and in form of elongated cllindircal sac. No appendages but the lophophore.
Lophophorate - trimeric construction: Protocoel, mesocoel and metacoel. Anterior body - mesocoel, bears lophophore and contains main nervous system. Trunk - metacoel, not specialized except for a bulb in the end (contains stomach and holds the aniaml in tube). Protocoel only in early stages, than reduced to epistome - a flap of tissue covering the mouth.
Body support by hydroskeleton, musculature weak, only limited movement if removed from tube.
Extensive circulatory system between lophophore and stomach - probably for nutrient and oxygen transport; have afferent and efferent branches and haemal plexus. No heart. Blood contains red blood particles with haemoglobin as respiratory pigment.
Excretion by pair of metanephridia in the trunk, each with 2 nephrostomes.
Asexual reproduction by budding or by transverse fission obseved in 2 species.
Separate sexes, some species hermaphroditic. Gametes excreted outside via nephridia, fertilization external.
All but 1 species have an unique actinotroph larva.
All marine and live in chitinous tubes implanted in muddy or sandy sediments or attached to solid surfaces; sessile, but can move within theit tubes. Have giant nerve fibre that allows the animal to withdraw rapidly. Found from intertidal to 400 m. ~12cm long, and in form of elongated cllindircal sac. No appendages but the lophophore.
Lophophorate - trimeric construction: Protocoel, mesocoel and metacoel. Anterior body - mesocoel, bears lophophore and contains main nervous system. Trunk - metacoel, not specialized except for a bulb in the end (contains stomach and holds the aniaml in tube). Protocoel only in early stages, than reduced to epistome - a flap of tissue covering the mouth.
Body support by hydroskeleton, musculature weak, only limited movement if removed from tube.
Extensive circulatory system between lophophore and stomach - probably for nutrient and oxygen transport; have afferent and efferent branches and haemal plexus. No heart. Blood contains red blood particles with haemoglobin as respiratory pigment.
Excretion by pair of metanephridia in the trunk, each with 2 nephrostomes.
Asexual reproduction by budding or by transverse fission obseved in 2 species.
Separate sexes, some species hermaphroditic. Gametes excreted outside via nephridia, fertilization external.
All but 1 species have an unique actinotroph larva.
Tue, Jun. 3rd, 1997, 04:49 pm
phylum Pogonophora.
From greek πογόν - beard and φόρω - to bear.
"annelid-like". Old philogenetic position - phylum Annelida, class Polychaeta, order Sabellida with only family Sibloglinidae.
Eumetazoa
Bilateria
Protostomata
Lophotrochozoa
Coelomata
Defining characteristics: Gut tissue (entoderm) forms a special organ (trophosome) that's filled with chaemosynthetic bacteria; segmentation confined to small rear position of the animal.
Small group of marine tube-dwelling worms originally discovered at the deep see off the coast of Indonesia in 1990. Almost exclusively deep-sea (>100m), sessile, live in sectreted stiff, chitinous tubes that are usually fixed at the bottom of ooze. Often occur in dense aggregations (>200/m2). Most are 10-85 cm, but most famous species Riftia pachyptila reaches 2 or 3 m. Some specimen believed to be more than 250 year old (probably the longest-living non-colonial animals).
Tube always longer than the animal, can move up and down in tube.
Each tentacle has 2 blood vessels - primary gas exchange surface. Anterior section has a small coelomic cavity that extends into tentacles.
Body divided into trunk and segmented opisthosoma. Trunk - longest part of a body, contains gonads and trophosome, closely packed with bacteria. A dense "beard" of tentacles at the end of the trunk. Opisthosoma - 6 to 25 segments in the bottom of the animal. Each segment contains a coelomic compartment, isolated by septae, and a pair of chitinous setae.
Body wall of outer circular, inner longitudinal muscles, external surface with papillae, cilia and setae.
No digestive system at all (some species have a complete annelid-like digestive system on early developmet stages, lost further in philogenesis). Feed by chaemosynthetic bacteria in the trochosoma. Usually attracted to hydrothermal vents that emit hot seawater rich in inorganic compounds such as H2S or CH4. Chemicals diffuse into body via tentacular plume and get carried with blood along with O2 (blood has haemoglobin). Then they are oxidized by the bacteria:
CO2 + 4H2S + O2 ==> [CH2O]n + 4S + 3H2O
Bacteria are ingested by the host or release carbohydrates to host tissue.
Also some found in cold hypersaline waters in Gulf of Mexico, that have H2S and CH4 deep through sediment.
Osedax frankpressi - grow on whale sceletons, found living in up to 2891 m. No trophosome, have "roots" that invade bone tissue and contain endosymbiotic bacteria. Sexually dimorphic - dwarf males live in female tubes (up to 111 per female).
A whole site about Osedax - http://www.osedax.com
Most are dioecious, few species known to have direct sperm transfer from males to females via sperm bundles, other are believed to have external fertilization.
"annelid-like". Old philogenetic position - phylum Annelida, class Polychaeta, order Sabellida with only family Sibloglinidae.
Eumetazoa
Bilateria
Protostomata
Lophotrochozoa
Coelomata
Defining characteristics: Gut tissue (entoderm) forms a special organ (trophosome) that's filled with chaemosynthetic bacteria; segmentation confined to small rear position of the animal.
Small group of marine tube-dwelling worms originally discovered at the deep see off the coast of Indonesia in 1990. Almost exclusively deep-sea (>100m), sessile, live in sectreted stiff, chitinous tubes that are usually fixed at the bottom of ooze. Often occur in dense aggregations (>200/m2). Most are 10-85 cm, but most famous species Riftia pachyptila reaches 2 or 3 m. Some specimen believed to be more than 250 year old (probably the longest-living non-colonial animals).
Tube always longer than the animal, can move up and down in tube.
Each tentacle has 2 blood vessels - primary gas exchange surface. Anterior section has a small coelomic cavity that extends into tentacles.
Body divided into trunk and segmented opisthosoma. Trunk - longest part of a body, contains gonads and trophosome, closely packed with bacteria. A dense "beard" of tentacles at the end of the trunk. Opisthosoma - 6 to 25 segments in the bottom of the animal. Each segment contains a coelomic compartment, isolated by septae, and a pair of chitinous setae.
Body wall of outer circular, inner longitudinal muscles, external surface with papillae, cilia and setae.
No digestive system at all (some species have a complete annelid-like digestive system on early developmet stages, lost further in philogenesis). Feed by chaemosynthetic bacteria in the trochosoma. Usually attracted to hydrothermal vents that emit hot seawater rich in inorganic compounds such as H2S or CH4. Chemicals diffuse into body via tentacular plume and get carried with blood along with O2 (blood has haemoglobin). Then they are oxidized by the bacteria:
CO2 + 4H2S + O2 ==> [CH2O]n + 4S + 3H2O
Bacteria are ingested by the host or release carbohydrates to host tissue.
Also some found in cold hypersaline waters in Gulf of Mexico, that have H2S and CH4 deep through sediment.
Osedax frankpressi - grow on whale sceletons, found living in up to 2891 m. No trophosome, have "roots" that invade bone tissue and contain endosymbiotic bacteria. Sexually dimorphic - dwarf males live in female tubes (up to 111 per female).
A whole site about Osedax - http://www.osedax.com
Most are dioecious, few species known to have direct sperm transfer from males to females via sperm bundles, other are believed to have external fertilization.
Tue, Jun. 3rd, 1997, 02:59 pm
phylum Sipuncula
Common name - peanut worms. "annelid-like", but no segmentation on any life stage, no prostomium, no setae.
Molecular analysis show that they might be closely related to molluscs.
Eumetazoa
Bilateria
Protostomata
Lophotrophozoa
Coelomata
Defining characteristics: anterior part of body forms an eversible introvert with a mouth on the end; multicellular bodies (urns) in coelomic fluid; anterior tentacles connected to muscular compensatory sacs.
Common name - peanut worms. About 350 living species. 2 to 200 mm length. All marine, cryptic, mostly beidge in colour. Mostly shallowwater-dwellers, some deepwater (7000 to 10000 m). Sedentary, deposit-feeding, live in rocks, gravel and mud and in empty mollusc shells or polychaete tubes. Can get to densities up to 700 per square meter in Hawaii, in Indo-Pacific are sometimes consumed as human food.
Body of trunk and fully-retractable introvert. Mouth on the end of introvert. Introvert from 1/2 to several times the length of body. Contract body wall muscles thrusts introvert out, retrcted with retractor muscle. Introvert often has mucus-covered tentacles, surrounding or next to the mouth - trap particles from water, or detritius. Draw introvert into the body and ingest or pass by cilia to mouth. Most are deposit-feeders.
Introvers vears mechanoreceptive cells. Also believed to have presumed chaemoreceptors (nuchal organs). May have light-sensistive ocelli within brain.
Body wall from external: collagen fibres; epidermis; circular muscles; longitudinal muscles; peritoneum lining coelom. Cuticle may have sclerotized parts ("cuticular spines").
U-shaped gut with mouth and dorsal anus at about the midpoint of trunk. Oesophagus leads to intestine coiled around spindle muscle. Digestion extracellular with intestinal lumen. Wastes out through anus.
Large coelomic cavity with no sign of segmentation in any life stage. Tentacles of introvert not associated with coelom and are connected with compensatin sac; contract of compensation sac drives fluid into the tentacles. Tentacles and compensation sac form second, lesser coelomic cavity - s.c. trunk coelom.
No circulatory system, but have haemoerythrin found in coelomic fluid cells (found in few invertebrates but some polychaetes).
Excretion most often by a single pair of metanephridia. Have urns - multicellular bodies in coelomic fluid that collect wastes. Gametes arise in coelomic lining, often near retractor muscles. Separate sexes. Gametes released through nephridia, fertilisation external. Cleavage spiral, typical molluscan cross at 64-cell stage. Most often typical trochophore larva. Can include a special life stage - pelagosphera, a long-living larva (up to 8 mounths before metamorphosis).
Molecular analysis show that they might be closely related to molluscs.
Eumetazoa
Bilateria
Protostomata
Lophotrophozoa
Coelomata
Defining characteristics: anterior part of body forms an eversible introvert with a mouth on the end; multicellular bodies (urns) in coelomic fluid; anterior tentacles connected to muscular compensatory sacs.
Common name - peanut worms. About 350 living species. 2 to 200 mm length. All marine, cryptic, mostly beidge in colour. Mostly shallowwater-dwellers, some deepwater (7000 to 10000 m). Sedentary, deposit-feeding, live in rocks, gravel and mud and in empty mollusc shells or polychaete tubes. Can get to densities up to 700 per square meter in Hawaii, in Indo-Pacific are sometimes consumed as human food.
Body of trunk and fully-retractable introvert. Mouth on the end of introvert. Introvert from 1/2 to several times the length of body. Contract body wall muscles thrusts introvert out, retrcted with retractor muscle. Introvert often has mucus-covered tentacles, surrounding or next to the mouth - trap particles from water, or detritius. Draw introvert into the body and ingest or pass by cilia to mouth. Most are deposit-feeders.
Introvers vears mechanoreceptive cells. Also believed to have presumed chaemoreceptors (nuchal organs). May have light-sensistive ocelli within brain.
Body wall from external: collagen fibres; epidermis; circular muscles; longitudinal muscles; peritoneum lining coelom. Cuticle may have sclerotized parts ("cuticular spines").
U-shaped gut with mouth and dorsal anus at about the midpoint of trunk. Oesophagus leads to intestine coiled around spindle muscle. Digestion extracellular with intestinal lumen. Wastes out through anus.
Large coelomic cavity with no sign of segmentation in any life stage. Tentacles of introvert not associated with coelom and are connected with compensatin sac; contract of compensation sac drives fluid into the tentacles. Tentacles and compensation sac form second, lesser coelomic cavity - s.c. trunk coelom.
No circulatory system, but have haemoerythrin found in coelomic fluid cells (found in few invertebrates but some polychaetes).
Excretion most often by a single pair of metanephridia. Have urns - multicellular bodies in coelomic fluid that collect wastes. Gametes arise in coelomic lining, often near retractor muscles. Separate sexes. Gametes released through nephridia, fertilisation external. Cleavage spiral, typical molluscan cross at 64-cell stage. Most often typical trochophore larva. Can include a special life stage - pelagosphera, a long-living larva (up to 8 mounths before metamorphosis).
Tue, Jun. 3rd, 1997, 02:05 pm
philum Echiura.
Common name - spoon worms. "annelid-like", but not segmented as adults and only show a short-lived trace of segmentation in embryogensis.
Eumetazoa
Bilateria
Protostomata
Lophotrochozoa
Coelomata
Defining characteristic: unique muscular organs (anal sacs) outpocketing from the rectum into the coelomic space, bearing numerous funnels, hat discharge coelomic fluids and wastes into the anus.
Name from greek έχις - serpent-like. About 140 species, 6 in NZ. Mostly shallowwater, 5 species deepwater. Live in sandy and muddy burroughs or rarely in rock crevices. Body cyllindrical or sausage-shaped, lengh varies from few mm up to 40 cm. Body may be smooth or warty; often have annelid-like setae just posterior to proboscis. Body divided into anterior, pre-oral proboscis and an enlarged trunk.
Proboscis cannot be withdrawn. It is muscular, mobile and can reach up to 25x length of the body (e.g., 200 cm of a 8cm individual). Proboscis is used for food collection and is ciliated on the ventral surface. Mud and detritius are caught by mucus secretions of proboscis and moved by the cilia into the mouth.
Proboscis contains the brain (may be homological to annelid prostomium).
Complete digestive system in the trunk; it is long and convolutes. Sometimes foregut is specialized to pharynx, oesophagus, gizzard and stomach; on other species it's uniform all along length. Mid-gut has a longitudinal groove called siphon that probably aids moving material along the gut. Anus opens posteriorly.
Coelom contains numerous mesenteries, but not separated by septa. Trunk coelom provides a hydrostatic skeleton. Non-separate coelom allows peristaltic burrowing.
1 to many hundreds (most often 1-5 pairs) of metanephridia in the anterior trunk region. Coelomic fluid drawn into nephrostome and excreted. Major functions may be gamete collection. Anal sacs also blieved to have excretory role. They are muscular and have ciliated funnels collecting coelomic fluid (though no evidence that composition altered). Periodic muscular contractions excrete them though anus.
Nervous system of anterior nerve ring and ventral nerve cord; no ganglia, no evidence of segmentation, no complex sensory receptors.
Simple closed circular system. Dorsal and venral vessels in trunk, medial and lateral vessels in proboscis. No heart. Blood pigmets usually absent, but red blood cells occur in coelomic fluid. Respiration by diffusion through body surface. In some species gas exchage through hindgut (water pumped in and out by muscle action).
No distinct gonads, gametes produced by peritoneal lining of coelom. Separate sexes, no sexual dimorphism. Eggs and sperm connected by nephridia and stored until release. Fertilisation external. Typical protostome development, trochophore larva.
Urechis Sp. - inn-keeper worm. Filter-feeding; mucus net attached to burrough wall by proboscis; water drawn through burrough by peristaltic movements of the body. Burroughs attract other commensal animals (polychaetes, crustaceans etc.)
Bonnelia viridis - have sexual dimorphism; females large, up to 2 m, males small, lack proboscis and often show remnants of larval ciliation. Males parasitic on female, don't have functional mouth or gut - mouth used to release sperm. May be up to 20 males on a female. Sex is environmentally determined. Females secret "male factor" that leads to development of males.
Eumetazoa
Bilateria
Protostomata
Lophotrochozoa
Coelomata
Defining characteristic: unique muscular organs (anal sacs) outpocketing from the rectum into the coelomic space, bearing numerous funnels, hat discharge coelomic fluids and wastes into the anus.
Name from greek έχις - serpent-like. About 140 species, 6 in NZ. Mostly shallowwater, 5 species deepwater. Live in sandy and muddy burroughs or rarely in rock crevices. Body cyllindrical or sausage-shaped, lengh varies from few mm up to 40 cm. Body may be smooth or warty; often have annelid-like setae just posterior to proboscis. Body divided into anterior, pre-oral proboscis and an enlarged trunk.
Proboscis cannot be withdrawn. It is muscular, mobile and can reach up to 25x length of the body (e.g., 200 cm of a 8cm individual). Proboscis is used for food collection and is ciliated on the ventral surface. Mud and detritius are caught by mucus secretions of proboscis and moved by the cilia into the mouth.
Proboscis contains the brain (may be homological to annelid prostomium).
Complete digestive system in the trunk; it is long and convolutes. Sometimes foregut is specialized to pharynx, oesophagus, gizzard and stomach; on other species it's uniform all along length. Mid-gut has a longitudinal groove called siphon that probably aids moving material along the gut. Anus opens posteriorly.
Coelom contains numerous mesenteries, but not separated by septa. Trunk coelom provides a hydrostatic skeleton. Non-separate coelom allows peristaltic burrowing.
1 to many hundreds (most often 1-5 pairs) of metanephridia in the anterior trunk region. Coelomic fluid drawn into nephrostome and excreted. Major functions may be gamete collection. Anal sacs also blieved to have excretory role. They are muscular and have ciliated funnels collecting coelomic fluid (though no evidence that composition altered). Periodic muscular contractions excrete them though anus.
Nervous system of anterior nerve ring and ventral nerve cord; no ganglia, no evidence of segmentation, no complex sensory receptors.
Simple closed circular system. Dorsal and venral vessels in trunk, medial and lateral vessels in proboscis. No heart. Blood pigmets usually absent, but red blood cells occur in coelomic fluid. Respiration by diffusion through body surface. In some species gas exchage through hindgut (water pumped in and out by muscle action).
No distinct gonads, gametes produced by peritoneal lining of coelom. Separate sexes, no sexual dimorphism. Eggs and sperm connected by nephridia and stored until release. Fertilisation external. Typical protostome development, trochophore larva.
Urechis Sp. - inn-keeper worm. Filter-feeding; mucus net attached to burrough wall by proboscis; water drawn through burrough by peristaltic movements of the body. Burroughs attract other commensal animals (polychaetes, crustaceans etc.)
Bonnelia viridis - have sexual dimorphism; females large, up to 2 m, males small, lack proboscis and often show remnants of larval ciliation. Males parasitic on female, don't have functional mouth or gut - mouth used to release sperm. May be up to 20 males on a female. Sex is environmentally determined. Females secret "male factor" that leads to development of males.
Tue, Jun. 3rd, 1997, 12:54 pm
phylum Gnathostomulida
Eumetazoa
Bilateria
Protostoma
Lophotrochozoa
Acoelomata
from Greek γνάθος - jaw and στόμα - mouth.
Determining features: unique jawed pharingeal apparatus, monociliated epidermal cells.
About 80 species of minute vermiform animals. Meiofauna - live between sediment grains. Size 62 μm or smaller. Often occur in high densities (>6000/kg) in anoxic, sulphide-rich conditions. Found in depths of hundreds of meters.
Elongate body divided into trunk, head and tail.
Triploblastic with loose mesenchyme; externally ciliated (only 1 cilia per cell). Move in a gliding motion. Have a mouth, tubular gut but no functional anus. No specialized circulatory or respiratory systems, excretory organs are 2 to 5 pairs of simple protonephridia. Mouthparts are used to scrap bacteria and fungi from sand grains and othe substrates.
Protandric or simultaneous hermaphrodites. Male system of 1-2 testes in posterior part of trunk and tail. Method of sperm transfer unknown. Penis is glandular and adheres to partner's body - sperm might bore through body wall.
Zygotes released into environment. Cleavage spiral, always direct development, i.e. no larval stages.
Phylogenetic position uncertain; believed to evolve neotenically from planula larva of cnidarians.
Bilateria
Protostoma
Lophotrochozoa
Acoelomata
from Greek γνάθος - jaw and στόμα - mouth.
Determining features: unique jawed pharingeal apparatus, monociliated epidermal cells.
About 80 species of minute vermiform animals. Meiofauna - live between sediment grains. Size 62 μm or smaller. Often occur in high densities (>6000/kg) in anoxic, sulphide-rich conditions. Found in depths of hundreds of meters.
Elongate body divided into trunk, head and tail.
Triploblastic with loose mesenchyme; externally ciliated (only 1 cilia per cell). Move in a gliding motion. Have a mouth, tubular gut but no functional anus. No specialized circulatory or respiratory systems, excretory organs are 2 to 5 pairs of simple protonephridia. Mouthparts are used to scrap bacteria and fungi from sand grains and othe substrates.
Protandric or simultaneous hermaphrodites. Male system of 1-2 testes in posterior part of trunk and tail. Method of sperm transfer unknown. Penis is glandular and adheres to partner's body - sperm might bore through body wall.
Zygotes released into environment. Cleavage spiral, always direct development, i.e. no larval stages.
Phylogenetic position uncertain; believed to evolve neotenically from planula larva of cnidarians.
Tue, Jun. 3rd, 1997, 11:37 am
phylum Nemertea.
Eumetazoa
Bilateria
Protostomata
Lophotrochozoa
Acoelomata
Defining characteristic: muscular eversible proboscis in a fluid-filled schizocoelous cavity.
Common name - ribbon worms. ~900 species. Name derived from the long muscular proboscis they can thrust out to grasp prey (Greek νεμέρτος - unerring one). Can vary in size from a few mm to several metres (up to 27m).
Most are benthic marine animals; some are commensal in gills of bivalves, crustaceans and ascidians; some species are planctonic in deep ocean waters, few terrestial (tropical moist areas) and freshwater.
Triploblastic, acoelomate, unsegmented. Ciliated externally, secret mucus through what they move; no hard cuticle or skeleton. Mesodermally-derived parenchyma as in flatworms.
Nervous system of cerebral ganglia and nervous cords, connected with connectives. Ganglia suround proboscis. Have sensory organs such as ciliated pits and ocelli.
Have protonephridia and flame cells.
Closed circulatory system of two main longitudinal vessels linked by transverse vessels. Blood vessels lined with mesoderm, what's unique for Nemertea. No heart or respiratory system. Pigmented blood cells - red, green, yellow or orange.
Complete gut. Internal organs surrounded by mesenchyme, no coelom. Digestion largely intracellular. Muscular body wall - internal longitudinal, outer circular.
Separate sexes, external fertilisation. Development - spiral cleavage. Direct development (juvenile looks lika a small adult). Pilidium larva with complex metamorphosis - only in order Heteronemertea.
Believed to be more closely related to coelomates than to flatworms. May be degenerate coelomates.
A whole site about nemertean anatomy:
http://nemertes.si.edu/Atlas/
Bilateria
Protostomata
Lophotrochozoa
Acoelomata
Defining characteristic: muscular eversible proboscis in a fluid-filled schizocoelous cavity.
Common name - ribbon worms. ~900 species. Name derived from the long muscular proboscis they can thrust out to grasp prey (Greek νεμέρτος - unerring one). Can vary in size from a few mm to several metres (up to 27m).
Most are benthic marine animals; some are commensal in gills of bivalves, crustaceans and ascidians; some species are planctonic in deep ocean waters, few terrestial (tropical moist areas) and freshwater.
Triploblastic, acoelomate, unsegmented. Ciliated externally, secret mucus through what they move; no hard cuticle or skeleton. Mesodermally-derived parenchyma as in flatworms.
Nervous system of cerebral ganglia and nervous cords, connected with connectives. Ganglia suround proboscis. Have sensory organs such as ciliated pits and ocelli.
Have protonephridia and flame cells.
Closed circulatory system of two main longitudinal vessels linked by transverse vessels. Blood vessels lined with mesoderm, what's unique for Nemertea. No heart or respiratory system. Pigmented blood cells - red, green, yellow or orange.
Complete gut. Internal organs surrounded by mesenchyme, no coelom. Digestion largely intracellular. Muscular body wall - internal longitudinal, outer circular.
Separate sexes, external fertilisation. Development - spiral cleavage. Direct development (juvenile looks lika a small adult). Pilidium larva with complex metamorphosis - only in order Heteronemertea.
Believed to be more closely related to coelomates than to flatworms. May be degenerate coelomates.
A whole site about nemertean anatomy:
http://nemertes.si.edu/Atlas/