21-655: The Gulf sturgeon ( Acipenser oxyrinchus desotoi ) is a subspecies of sturgeon that lives in the Gulf of Mexico and some rivers draining into it. The Gulf sturgeon was first recognized as a separate subspecies in 1955. The nominate subspecies is the Atlantic sturgeon , A. o. oxyrinchus . The Gulf sturgeon is listed as threatened under the United States Endangered Species Act , having been listed in 1991. Critical habitat , reflecting
42-529: A separate description is warranted. These distinct groups do not interbreed as they are isolated from another, but they can interbreed and have fertile offspring, e.g. in captivity. These subspecies, races, or populations, are usually described and named by zoologists, botanists and microbiologists. In a monotypic species, all populations exhibit the same genetic and phenotypical characteristics. Monotypic species can occur in several ways: Trematode Too Many Requests If you report this error to
63-483: A species is a binomial or binomen, and comprises two Latin words, the first denoting the genus and the second denoting the species. The scientific name of a subspecies is formed slightly differently in the different nomenclature codes. In zoology, under the International Code of Zoological Nomenclature (ICZN), the scientific name of a subspecies is termed a trinomen , and comprises three words, namely
84-426: A species. Botanists and mycologists have the choice of ranks lower than subspecies, such as variety (varietas) or form (forma), to recognize smaller differences between populations. In biological terms, rather than in relation to nomenclature, a polytypic species has two or more genetically and phenotypically divergent subspecies, races , or more generally speaking, populations that differ from each other so that
105-417: A subspecies. A common criterion for recognizing two distinct populations as subspecies rather than full species is the ability of them to interbreed even if some male offspring may be sterile. In the wild, subspecies do not interbreed due to geographic isolation or sexual selection . The differences between subspecies are usually less distinct than the differences between species. The scientific name of
126-438: Is a rank below species , used for populations that live in different areas and vary in size, shape, or other physical characteristics ( morphology ), but that can successfully interbreed. Not all species have subspecies, but for those that do there must be at least two. Subspecies is abbreviated as subsp. or ssp. and the singular and plural forms are the same ("the subspecies is" or "the subspecies are"). In zoology , under
147-469: Is a subspecies or a full species, the species name may be written in parentheses. Thus Larus (argentatus) smithsonianus means the American herring gull ; the notation within the parentheses means that some consider it a subspecies of a larger herring gull species and therefore call it Larus argentatus smithsonianus , while others consider it a full species and therefore call it Larus smithsonianus (and
168-559: The International Code of Zoological Nomenclature , the subspecies is the only taxonomic rank below that of species that can receive a name. In botany and mycology , under the International Code of Nomenclature for algae, fungi, and plants , other infraspecific ranks , such as variety , may be named. In bacteriology and virology , under standard bacterial nomenclature and virus nomenclature , there are recommendations but not strict requirements for recognizing other important infraspecific ranks. A taxonomist decides whether to recognize
189-453: The binomen followed by the name of the subspecies. For example, the binomen for the leopard is Panthera pardus . The trinomen Panthera pardus fusca denotes a subspecies, the Indian leopard . All components of the trinomen are written in italics. In botany , subspecies is one of many ranks below that of species, such as variety , subvariety , form , and subform. To identify the rank,
210-413: The natal river, generally over a hard bottom just downstream of a spring on the river bottom feeding groundwater into the river. After spawning, the adults and older juveniles collect in regions of cooler, deeper, slower-flowing water, generally downstream of springs. All species of sturgeon leap out of the water at times. The Gulf sturgeon tends to jump during July and August, and again early during
231-539: The offshore feeding period. They are thought to jump to communicate and maintain group cohesion. Due to their heavy body armor, large leaping sturgeon can inflict serious injuries to humans who are in the way. On July 2, 2015, a leaping sturgeon on the Suwannee River in Florida struck and killed a 5-year-old girl. Predators of the sturgeon, other than humans, are unknown, but thought to have limited impact upon
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#1732780590018252-529: The other sturgeon species is anadromous . Visually, Gulf sturgeon are almost impossible to differentiate from Atlantic sturgeon, as the most significant morphological difference is the spleen length, which is internal. Gulf sturgeon have a spleen length averaging 12.3% of their fork length , while Atlantic sturgeon have a spleen length averaging 5.7% of their fork length. Lesser morphological differences include relative head length, shape of dorsal scutes , and pectoral fin length. Genetic differences between
273-602: The range of the subspecies deemed essential for its continued survival, has been designated (see map). The historical range is thought to have been from the Suwannee River on the western coast of Florida to the Mississippi River , and marine waters of the central and eastern portions of the Gulf of Mexico. Three sturgeon species in genus Scaphirhynchus share river territory with the Gulf sturgeon; none of
294-467: The rank of variety are taken to be names of subspecies (see International Code of Nomenclature of Prokaryotes ). As in botany, subspecies is conventionally abbreviated as "subsp.", and is used in the scientific name: Bacillus subtilis subsp. spizizenii . In zoological nomenclature , when a species is split into subspecies, the originally described population is retained as the "nominotypical subspecies" or "nominate subspecies", which repeats
315-418: The same name as the species. For example, Motacilla alba alba (often abbreviated M. a. alba ) is the nominotypical subspecies of the white wagtail ( Motacilla alba ). The subspecies name that repeats the species name is referred to in botanical nomenclature as the subspecies " autonym ", and the subspecific taxon as the "autonymous subspecies". When zoologists disagree over whether a certain population
336-548: The spawning river until roughly two years of age, eating there. Thereafter, they join the adults in their anadromous migrations and eating habits. The upriver migration normally occurs between February and April, as river temperatures rise to 16 to 23 °C (61 to 73 °F). Downriver migration normally begins in late September or October when water temperatures drop to 23 °C (73 °F). Males reach sexual maturity between seven and 12 years of age, females between eight and 17 years of age. Spawning almost always occurs in
357-482: The species. Parasites include the fish louse Argulus stizostehi , nematodes , trematodes , and leeches . No detrimental impacts from these parasites have been observed. The species also serves as host to the glochidia (larvae) of three freshwater mussel species. Overfishing and dam construction probably contributed to the historical decline in populations. [REDACTED] Subspecies In biological classification , subspecies ( pl. : subspecies)
378-543: The subspecies have been studied, and tend to indicate reproductive isolation occurred in the Pleistocene period. Behavioral differences are more clear, especially the dietary habits. Adult Gulf sturgeon eat primarily, or possibly only, during the winter, when they are in marine or brackish water , and eat little to nothing during the remainder of the year when they are in rivers. Their weights vary in accordance with this eating pattern, with significant weight gains in
399-563: The subspecific name must be preceded by "subspecies" (which can be abbreviated to "subsp." or "ssp."), as in Schoenoplectus californicus subsp. tatora . In bacteriology , the only rank below species that is regulated explicitly by the code of nomenclature is subspecies , but infrasubspecific taxa are extremely important in bacteriology; Appendix 10 of the code lays out some recommendations that are intended to encourage uniformity in describing such taxa. Names published before 1992 in
420-425: The user of the notation is not taking a position). A subspecies is a taxonomic rank below species – the only such rank recognized in the zoological code, and one of three main ranks below species in the botanical code. When geographically separate populations of a species exhibit recognizable phenotypic differences, biologists may identify these as separate subspecies; a subspecies is a recognized local variant of
441-434: The winter and smaller weight losses in the summer. Because their diet consists of mollusks that can cause paralytic shellfish poisoning (PSP), in addition to other bottom-dwelling organisms such as grass shrimp , marine worms, isopods , and amphipods , their unique feeding pattern possibly reflects an adaptation to prevent PSP that coincides with higher rates of algal blooms in summer. Juvenile Gulf sturgeon remain in
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