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Gadopsis
''Gadopsis'' is a genus of temperate perches endemism, endemic to freshwater habitats in southeastern Australia. The genus was formerly considered to be in a family of its own, Gadopsidae. This genus and the ''Maccullochella'' cods (such as the Murray cod, ''Maccullochella peelii'') are strongly similar. There are some grounds for believing blackfish may be a smaller version of Murray cod, inhabiting similar niches but in habitats are too small for Murray cod (having said this, their distributions originally overlapped substantially), and there are grounds for believing that blackfish and Murray cod have drawn heavily on common genes at the family level. FishBase, for instance, has scrapped the family Gadopsidae and listed the blackfishes as members of the temperate perch family, ''Percichthyidae''. A mitochondrial DNA study has confirmed a relationship between the Blackfish and the Percichthyidae but the exact relationship was not resolved in that study. Further study is need ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gadopsis Marmoratus
The river blackfish (''Gadopsis marmoratus'') is a freshwater fish endemic to the temperate waters of south-eastern Australia. It is found from southern Queensland through to central Victoria, including in the Murray- Darling river system. It is also found in some eastern and southern flowing coastal rivers. Found primarily in upland and "midland" habitats, though early records of fish fauna suggest it was originally far more extensively distributed and was found in some lowland habitats as well. Originally, river blackfish co-inhabited many of its lowland and "midland" habitats with species such as Murray cod and golden perch, and its upland habitats with species such as trout cod and Macquarie perch. It is a popular angling fish in some parts of its range. Description River blackfish are elongated with a rounded body, distinct snout and large mouth, and small to moderate sized eyes. The caudal fin, soft dorsal fin and anal fin are rounded. The spiny dorsal fin is low, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gadopsis Bispinosus
The two-spined blackfish (''Gadopsis bispinosus'') is a species of temperate perch endemic to Australia. It is found in the cool, clear, strong-flowing, cobble bottomed, sub-alpine rivers and streams (ranging from small to large) in the southeast corner of the Murray- Darling river system. Their range encompasses northeast Victoria, southeast New South Wales and the Australian Capital Territory. Originally two-spined blackfish co-inhabited many of these waters with Macquarie perch and trout cod. Two-spined blackfish are similar in shape and appearance to river blackfish, though their spiny dorsal fin usually contain only two spines (hence their scientific name) in comparison to river blackfish which have 7 to 13 distinguishable spines in their spiny dorsal fin. (In reality, this is a rather academic point as two-spined blackfish have blurred the difference between the dorsal spines and the dorsal rays that make up their soft dorsal fin, and any distinctions between the t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temperate Perch
Percichthyidae, the temperate perches, are a family of freshwater ray-finned fish found in Australia and southern South America. Formerly placed in the order Perciformes, they are now placed in the order Centrarchiformes. The name Percichthyidae derives from the Latin ''perca'' for perch and Ancient Greek ἰχθύς, ''ichthys'' for fish. Evolution Potential percichthyid fossil remains are known from the Early Paleocene of the El Molino Formation of Bolivia; these remains have been described as resembling those of the fossil '' Percichthys hondoensis'' from the Eocene of Argentina. One articulated specimen is known from the Paleocene portion of the formation, but other remains are known from the Maastrichtian beds of the formation, indicating that percichthyids could have potential Cretaceous origins. However, the condition of this material is unclear. Another fossil percichthyid, '' Percichthys lonquimayiensis'' from Chile, was initially dated to the Paleocene, but further ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Complex
In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each other, further blurring any distinctions. Terms that are sometimes used synonymously but have more precise meanings are cryptic species for two or more species hidden under one species name, sibling species for two (or more) species that are each other's closest relative, and species flock for a group of closely related species that live in the same habitat. As informal taxonomic ranks, species group, species aggregate, macrospecies, and superspecies are also in use. Two or more taxa that were once considered conspecific (of the same species) may later be subdivided into infraspecific taxa (taxa within a species, such as plant variety (botany), varieties), which may be a complex ranking but it is not a species complex. In most cases, a specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxa Named By John Richardson (naturalist)
In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion, especially in the context of rank-based (" Linnaean") nomenclature (much less so under phylogenetic nomenclature). If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were presumably set forth in prehistoric times by hunter-gatherers, as suggested by the fairly sophisticated folk taxonomies. Much later, Aristotle, and later still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andrew C
Andrew is the English form of the given name, common in many countries. The word is derived from the , ''Andreas'', itself related to ''aner/andros'', "man" (as opposed to "woman"), thus meaning "manly" and, as consequence, "brave", "strong", "courageous", and "warrior". In the King James Bible, the Greek "Ἀνδρέας" is translated as Andrew. Popularity In the 1990s, it was among the top ten most popular names given to boys in English-speaking countries. Australia In 2000, the name Andrew was the second most popular name in Australia after James. In 1999, it was the 19th most common name, while in 1940, it was the 31st most common name. Andrew was the first most popular name given to boys in the Northern Territory in 2003 to 2015 and continuing. In Victoria, Andrew was the first most popular name for a boy in the 1970s. Canada Andrew was the 20th most popular name chosen for male infants in 2005. Andrew was the 16th most popular name for infants in British Columbia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snags
In forest ecology, a snag is a standing dead or dying tree, often missing a top or most of the smaller branches. In freshwater ecology the term ''snag'' refers to trees, branches, and other pieces of naturally occurring wood found sunken in rivers and streams; it is also known as coarse woody debris. Snags provide habitat for a wide variety of wildlife but pose hazards to river navigation. When used in manufacturing, especially in Scandinavia, they are often called dead wood and in Finland, kelo wood. Forest snags Snags are an important structural component in forest communities, making up 10–20% of all trees present in old-growth tropical, temperate, and boreal forests. Snags and downed coarse woody debris represent a large portion of the woody biomass in a healthy forest. In temperate forests, snags provide critical habitat for more than 100 species of bird and mammal, and snags are often called 'wildlife trees' by foresters. Dead, decaying wood supports a rich communit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondrial DNA
Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondrion, mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in a eukaryotic cell; most of the DNA is in the cell nucleus, and, in plants and algae, the DNA also is found in plastids, such as chloroplasts. Mitochondrial DNA is responsible for coding of 13 essential subunits of the complex oxidative phosphorylation (OXPHOS) system which has a role in cellular energy conversion. Human mitochondrial DNA was the first significant part of the human genome to be sequenced. This sequencing revealed that human mtDNA has 16,569 base pairs and encodes 13 proteins. As in other vertebrates, the human mitochondrial genetic code differs slightly from nuclear DNA. Since animal mtDNA evolves faster than nuclear genetic markers, it represents a mainstay of phylogenetics and evolutionary biology. It als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Richardson (naturalist)
Sir John Richardson Royal Society of London, FRS FRSE (5 November 1787 – 5 June 1865) was a Scotland, Scottish naval surgeon, natural history, naturalist and Arctic explorer. Life Richardson was born at Nith Place in Dumfries the son of Gabriel Richardson, Provost of Dumfries, and his wife, Anne Mundell. He was educated at Dumfries Grammar School. He was then apprenticed to his maternal uncle, Dr James Mundell, a surgeon in Dumfries. Richardson studied medicine at Edinburgh University, and became a surgeon in the navy in 1807. He traveled with John Franklin in search of the Northwest Passage on the Coppermine Expedition of 1819–1822. Richardson wrote the sections on geology, botany and ichthyology for the official account of the expedition. Franklin and Richardson Mackenzie River expedition, returned to Canada in 1825 and went overland by fur trade routes to the mouth of the Mackenzie River. Franklin was to go as far west as possible and Richardson was to go east to the mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
