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Disconatis Contubernalis
''Disconatis contubernalis'' is only known from Australia where it is commensal in the tubes of marine annelids of the family Maldanidae.Hanley, J. Russell and Burke, Melanie 1988. A new genus and species of commensal scaleworm (Polychaeta: Polynoidae). The Beagle, Records of the Northern Territory Museum of Arts and Sciences, 5(1): 5–15. Description ''Disconatis contubernalis'' has up to 152 segments and 22–80 pairs of elytra; the first pair are much larger than the following elytra which have a few large papillae on the surface. ''Disconatis conturbernalis'' which has large papillae on the elytra but a smooth body, in contrast with the other species in the genus, '' Disconatis accolus'', which has smooth elytra but with minute papillae on the dorsal surface of the body. The lateral antennae are inserted ventral to the median antenna. Notopodia are vestigial and notochaetae are absent, while the neuropodium is rounded and the neurochaetae are unidentate but have serrat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australia
Australia, officially the Commonwealth of Australia, is a sovereign ''Sovereign'' is a title which can be applied to the highest leader in various categories. The word is borrowed from Old French , which is ultimately derived from the Latin , meaning 'above'. The roles of a sovereign vary from monarch, ruler or ... country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. With an area of , Australia is the largest country by area in Oceania and the world's sixth-largest country. Australia is the oldest, flattest, and driest inhabited continent, with the least fertile soils. It is a megadiverse country, and its size gives it a wide variety of landscapes and climates, with deserts in the centre, tropical Forests of Australia, rainforests in the north-east, and List of mountains in Australia, mountain ranges in the south-east. The ancestors of Aboriginal Australians began arriving from south east Asia approx ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commensal
Commensalism is a long-term biological interaction ( symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit from each other; amensalism, where one is harmed while the other is unaffected; parasitism, where one is harmed and the other benefits, and parasitoidism, which is similar to parasitism but the parasitoid has a free-living state and instead of just harming its host, it eventually ends up killing it. The commensal (the species that benefits from the association) may obtain nutrients, shelter, support, or locomotion from the host species, which is substantially unaffected. The commensal relation is often between a larger host and a smaller commensal; the host organism is unmodified, whereas the commensal species may show great structural adaptation consistent with its habits, as in the remoras that ride attached to sharks and other fish ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maldanidae
Maldanidae is a family of more than 200 species of marine polychaetes commonly known as bamboo worms or maldanid worms. They belong to the order Capitellida, in the phylum Annelida. They are most closely related to family Arenicolidae, and together form the clade Maldanomorpha. Morphology Maldanid worms have a long and cylindrical body that usually bends at one or both ends. It can be divided into four parts: 1) a head, formed by a dorsally positioned prostomium that is fused to the peristomium, sometimes with a flattened cephalic plate; 2) a thorax, formed by the first four chaetigers (i.e. chaetae-bearing segments), usually with strong spines; 3) an abdomen, with several longer chaetigers that are often followed by a number of achaetous (i.e. without chaetae) segments; 4) a posterior end, with a pygidium that contains the anus. The maldanid pygidium takes a wide variety of forms such as conical, plate-shaped and funnel-shape. Sometimes a few prepygidial (i.e. anterior to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elytron (Annelida)
In annelids, elytra (; from Greek ἔλυτρον "sheath, cover"; singular: elytron ) are shield-like scales that are attached dorsally, one pair on each of a number of alternating segments and entirely or partly cover the dorsum. Elytra are modified dorsal cirri, and their number, size, location, and ornamentation are important taxonomic characters. The basal part of the elytra is known as the elytrophore; if (as is often the case) elytra are lost their presence is indicated by the elytrophore which is still present and visible. Annelids possessing elytra are also known as "scale worms". Possession of elytra is characteristic of the annelid suborder Aphroditiformia. Gallery File:Eunoe leiotentaculata lower res.jpg, A ''Eunoe leiotentaculata'' specimen showing its 15 pairs of elytra. File:Euphione sp. dorsal.jpg, ''Euphione ''Euphione'' is a genus of polychaetes belonging to the family Polynoidae. The species of this genus are found in Australia, Malesia Malesia is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disconatis Accolus
''Disconatis accolus'' is only known from New Zealand where it is commensal in the tubes of marine annelids of the family Arenicolidae.Estcourt, I. N. 1967. Burrowing polychaete worms from a New Zealand estuary. Transactions of the Royal Society of New Zealand, Ser. Zoology, 9(7): 65–78. Description ''Disconatis accolus'' is known from a single specimen with 152 segments and 76 pairs of elytra; the first pair are much larger than the following. It has smooth elytra but with minute papillae on the dorsal surface of the body, in contrast with the other species in the genus, ''Disconatis contubernalis'' which has large papillae on the elytra but a smooth body. The lateral antennae are inserted ventral to the median antenna. Notopodia are vestigial and notochaetae are absent. The neuropodia are rounded and the neurochaetae are unidentate but have serrations on the convex side. Biology and ecology ''Disconatis accolus'' has a commensal relationship with the annelid ''Abareni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parapodium
In invertebrates, the term parapodium ( Gr. ''para'', beyond or beside + ''podia'', feet; plural: parapodia) refers to lateral outgrowths or protrusions from the body. Parapodia are predominantly found in annelids, where they are paired, unjointed lateral outgrowths that bear the chaetae. In several groups of sea snails and sea slugs, 'parapodium' refers to lateral fleshy protrusions. __TOC__ Annelid parapodia Most species of polychaete annelids have paired, fleshy parapodia which are segmentally arranged along the body axis. Parapodia vary greatly in size and form, reflecting a variety of functions, such as gas exchange, anchorage, protection and locomotion. General description Parapodia in polychaetes can be uniramous (consisting of one lobe or ramus) but are usually biramous (two lobes or rami). In the latter case, the dorsal lobes are called notopodia and the ventral lobes neuropodia. Both neuropodia and notopodia may possess a bundle of chaetae (neurochaetae and notoch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaeta
A chaeta or cheta (from Greek χαίτη “crest, mane, flowing hair"; plural: chaetae) is a chitinous bristle or seta found in annelid worms, (although the term is also frequently used to describe similar structures in other invertebrates such as arthropods). Polychaete annelids, ('polychaeta' literally meaning "many bristles") are named for their chaetae. In Polychaeta, chaetae are found as bundles on the parapodia, paired appendages on the side of the body. The chaetae are epidermal extracellular structures, and clearly visible in most polychaetes. They are probably the best studied structures in these animals. Use in taxonomy and identification The ultrastructure of chaetae is fundamentally similar for all taxa but there is vast diversity in chaetal morphology. Moreover, chaetae bear precise characters for determination of species and taxonomic assessment. The shape, absolute and relative size, number, position, ornamentation and type are important taxonomic characters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
