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57-402: Antechinus (/ æntɪˈkaɪnəs / ('ant-echinus')) is a genus of small dasyurid marsupial endemic to Australia . They resemble mice with the bristly fur of shrews . They are also sometimes called 'broad-footed marsupial mice', 'pouched mice', or 'Antechinus shrews'. However, the majority of those common names are considered either regional or archaic; the modern common name for the animal

114-487: A high metabolic rate and normothermic temperatures of around 35 °C (95 °F). Going into torpor allows them to greatly reduce metabolic rates, sometimes up to 80% This reduces both the food and water requirements of the animal. Torpor in Antechinus usually occurs during rest periods, either in the early morning after nightly foraging or the late afternoon before nightly foraging. However, going into torpor during

171-651: A later homonym of a validly published name is a nomen illegitimum or nom. illeg. ; for a full list refer to the International Code of Nomenclature for algae, fungi, and plants and the work cited above by Hawksworth, 2010. In place of the "valid taxon" in zoology, the nearest equivalent in botany is " correct name " or "current name" which can, again, differ or change with alternative taxonomic treatments or new information that results in previously accepted genera being combined or split. Prokaryote and virus codes of nomenclature also exist which serve as

228-628: A long time and redescribed as new by a range of subsequent workers, or if a range of genera previously considered separate taxa have subsequently been consolidated into one. For example, the World Register of Marine Species presently lists 8 genus-level synonyms for the sperm whale genus Physeter Linnaeus, 1758, and 13 for the bivalve genus Pecten O.F. Müller, 1776. Within the same kingdom, one generic name can apply to one genus only. However, many names have been assigned (usually unintentionally) to two or more different genera. For example,

285-409: A reference for designating currently accepted genus names as opposed to others which may be either reduced to synonymy, or, in the case of prokaryotes, relegated to a status of "names without standing in prokaryotic nomenclature". An available (zoological) or validly published (botanical) name that has been historically applied to a genus but is not regarded as the accepted (current/valid) name for

342-623: A second year go into torpor much more frequently than females that are in their first year, even though second-year females are larger. It is thought that this is because first-year females are still growing and thus need more food which requires more time spent foraging. Older females are also more experienced at foraging and may meet their energy requirements more efficiently. A. arktos and A. argentus are currently listed as endangered . The main threats to these species, indeed all species of Antechinus , are habitat destruction and introduced animals. Deforestation and habitat destruction removes

399-427: A taxon; however, the names published in suppressed works are made unavailable via the relevant Opinion dealing with the work in question. In botany, similar concepts exist but with different labels. The botanical equivalent of zoology's "available name" is a validly published name . An invalidly published name is a nomen invalidum or nom. inval. ; a rejected name is a nomen rejiciendum or nom. rej. ;

456-455: A total of c. 520,000 published names (including synonyms) as at end 2019, increasing at some 2,500 published generic names per year. "Official" registers of taxon names at all ranks, including genera, exist for a few groups only such as viruses and prokaryotes, while for others there are compendia with no "official" standing such as Index Fungorum for fungi, Index Nominum Algarum and AlgaeBase for algae, Index Nominum Genericorum and

513-568: A very small part of their diet. Increasing the occurrences of torpor, in both males and females, is thought to help with survival after an intense bushfire by reducing the need for foraging and thus avoiding predators. It has been shown that smoke, ash and charcoal provide a cue for torpor induction. Increasing body temperature after torpor is energetically costly and reduces some of the metabolic savings. However, animals have been observed basking to help increase their body temperature without increasing their food intake. Females that have survived to

570-620: Is a possible genetic link that would allow for the selection of specific responses to different rates of change of photoperiod. The slightly different timings of reproduction by these sympatric species may also mean that they can take advantage of different increases of food in the spring and summer. Larger species of Antechinus usually mate first, meaning that the smaller species may have evolved later mating times to reduce competition and capitalise on later increases in food. A. swainsonii and A. minimums occur in Tasmania and their reliance on

627-552: Is antechinus. Antechinus have short fur and are generally greyish or brownish in colour, varying with species. The fur is dense and generally soft. Their tails are thin and tapering and range from slightly shorter to slightly longer than body length. Their heads are conical in shape and ears are small to medium in size. Some species have a relatively long, narrow snout that gives them a shrew-like appearance. Species vary from 12–31 cm (4.7–12.2 in) in length and weigh 16–170 g (0.56–6.00 oz) when fully grown. A. agilis

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684-416: Is called spontaneous torpor. Induced torpor occurs when food and water are restricted – this is most easily observed in a laboratory environment as restriction of food in the wild is hard to determine. Torpor of Antechinus in the wild is likely to be the result of a combination of factors. Antechinus are small mammals and thus have a high surface/volume ratio which results in high heat loss. They also have

741-612: Is discouraged by both the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants , there are some five thousand such names in use in more than one kingdom. For instance, A list of generic homonyms (with their authorities), including both available (validly published) and selected unavailable names, has been compiled by the Interim Register of Marine and Nonmarine Genera (IRMNG). The type genus forms

798-407: Is intense for Antechinus and can last up to 12 hours in some species. The males mate with a number of females and the litters have a number of fathers. During the short breeding window, males expand their home range and are often active during night and day. Males disperse from the nests once they are physiologically independent. Mothers initiate that dispersal but are tolerant of unrelated males in

855-514: Is likely to occur most commonly when the Antechinus are food stressed. The remains of plants have been found in Antechinus stool, likely accidentally ingested while searching for other food. Studies on Antechinus diet usually use faecal samples which may be unreliable in detecting soft bodied prey. Antechinus are usually classified as dietary generalists as they eat a wide variety of invertebrates as well as some vertebrates. They are also classified as opportunists because they feed on most of

912-427: Is long term (weeks or months) and daily torpor which is usually only a few hours. Daily torpor involves a less extreme lowering of body temperature and metabolic rate than hibernation. Antechinus undergo daily torpor. Unlike hibernation, daily torpor is not simply reliant on ambient air temperatures. Antechinus can move into torpor on summer days with temperatures in the range of 25–30 °C (77–86 °F). This

969-460: Is somewhat arbitrary. Although all species within a genus are supposed to be "similar", there are no objective criteria for grouping species into genera. There is much debate among zoologists about whether enormous, species-rich genera should be maintained, as it is extremely difficult to come up with identification keys or even character sets that distinguish all species. Hence, many taxonomists argue in favor of breaking down large genera. For instance,

1026-474: Is the type species , and the generic name is permanently associated with the type specimen of its type species. Should the specimen turn out to be assignable to another genus, the generic name linked to it becomes a junior synonym and the remaining taxa in the former genus need to be reassessed. In zoological usage, taxonomic names, including those of genera, are classified as "available" or "unavailable". Available names are those published in accordance with

1083-417: Is the smallest known species, and A. swainsonii the largest. Sexual dimorphism occurs in most species for both weight and skeletal measurements, with males being typically larger and heavier. Most species nest communally in tree-hollows. They primarily inhabit all forests , woodlands and rainforest as well as heaths and grasslands in some species. The majority of Antechinus species are located on

1140-621: The International Code of Zoological Nomenclature ; the earliest such name for any taxon (for example, a genus) should then be selected as the " valid " (i.e., current or accepted) name for the taxon in question. Consequently, there will be more available names than valid names at any point in time; which names are currently in use depending on the judgement of taxonomists in either combining taxa described under multiple names, or splitting taxa which may bring available names previously treated as synonyms back into use. "Unavailable" names in zoology comprise names that either were not published according to

1197-824: The International Plant Names Index for plants in general, and ferns through angiosperms, respectively, and Nomenclator Zoologicus and the Index to Organism Names for zoological names. Totals for both "all names" and estimates for "accepted names" as held in the Interim Register of Marine and Nonmarine Genera (IRMNG) are broken down further in the publication by Rees et al., 2020 cited above. The accepted names estimates are as follows, broken down by kingdom: The cited ranges of uncertainty arise because IRMNG lists "uncertain" names (not researched therein) in addition to known "accepted" names;

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1254-419: The nomenclature codes , which allow each species a single unique name that, for animals (including protists ), plants (also including algae and fungi ) and prokaryotes ( bacteria and archaea ), is Latin and binomial in form; this contrasts with common or vernacular names , which are non-standardized, can be non-unique, and typically also vary by country and language of usage. Except for viruses ,

1311-404: The platypus belongs to the genus Ornithorhynchus although George Shaw named it Platypus in 1799 (these two names are thus synonyms ) . However, the name Platypus had already been given to a group of ambrosia beetles by Johann Friedrich Wilhelm Herbst in 1793. A name that means two different things is a homonym . Since beetles and platypuses are both members of the kingdom Animalia,

1368-619: The Silver-headed Antechinus , Antechinus argentus sp. nov. (Marsupialia: Dasyuridae) Genus The composition of a genus is determined by taxonomists . The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: Moreover, genera should be composed of phylogenetic units of

1425-399: The availability of food for supporting the young. Females with fewer nipples are more likely to survive until the next breeding season. This is thought to be because it is less stressful to raise a smaller litter. The rate of survival of females to reproduce twice differs between species. The larger species, e.g. A. swainsonii are more likely to survive to reproduce for a second time. Mating

1482-442: The base for higher taxonomic ranks, such as the family name Canidae ("Canids") based on Canis . However, this does not typically ascend more than one or two levels: the order to which dogs and wolves belong is Carnivora ("Carnivores"). The numbers of either accepted, or all published genus names is not known precisely; Rees et al., 2020 estimate that approximately 310,000 accepted names (valid taxa) may exist, out of

1539-457: The breeding season. Males have been selected to be ready before the females to ensure the maximum amount of time for mating. Antechinus do not have a complete pouch, as in other marsupials, but simply a flap of skin covering the teats. The number of teats in Antechinus species varies between different populations of the same species, and can be anywhere from six to 13. Populations in which females have six teats are found in lower latitudes where

1596-891: The complex understorey habitat which Antechinus require for protection from predators and for food. Antechinus also nest in tree hollows, which only form in senescent trees. Introduced predators also threaten Antechinus populations with foxes and cats predating upon Antechinus . There is also competition between Antechinus and introduced rats and mice for habitat and food which may be detrimental to Antechinus numbers. Pigs, cattle and horses trample their habitats. Changed fire regimes since European arrival have resulted in more intense bushfires which can negatively impact Antechinus populations by destroying understorey vegetation and removing most of their preferred food. Climate change threatens several high altitude species, especially those in northern Queensland. A new dasyurid marsupial from Kroombit Tops, south-east Queensland, Australia:

1653-410: The different ranges of the various species of Antechinus , a reason for different species having different mating seasons. Many species of Antechinus occur sympatrically . Whenever two or more species of Antechinus occur together, the critical rate of change of photoperiod which triggers ovulation differs between the species. This reproductive isolation may have led to sympatric speciation . There

1710-523: The eastern coast of Australia along the Great Dividing Range . There is a population of A. flavipes in south west Western Australia . A. bellus lives in northern Australia around the Gulf of Carpentaria . There are currently 15 recognised species of Antechinus with a number of subspecies. A few species of New Guinean Antechinus were recognised, but they have been reclassified into

1767-408: The environment is more stable. In higher latitudes, there are populations with eight to 12 nipples. Odd numbers of teats only occur in transition zones and probably occur when populations with a different number of teats mate. The number of nipples is thought to correlate with the number of young that can be supported. In more seasonal environments, where more nipples occur, there is a larger increase in

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1824-527: The exact composition of their diet can vary by species and habitat. Antechinus mainly eat beetles, insect larvae and spiders. Amphipods , millipedes and centipedes are also quite common in their diets. It has been found that after a fire, ants make up the majority of their diet - this is thought to be because ants are the only insect present in any number after the fire. It has been reported that Antechinus also eat vertebrates, mainly small reptiles, such as skinks , or mammals, such as feathertail gliders . This

1881-446: The form "author, year" in zoology, and "standard abbreviated author name" in botany. Thus in the examples above, the genus Canis would be cited in full as " Canis Linnaeus, 1758" (zoological usage), while Hibiscus , also first established by Linnaeus but in 1753, is simply " Hibiscus L." (botanical usage). Each genus should have a designated type , although in practice there is a backlog of older names without one. In zoology, this

1938-737: The generic name (or its abbreviated form) still forms the leading portion of the scientific name, for example, Canis lupus lupus for the Eurasian wolf subspecies, or as a botanical example, Hibiscus arnottianus ssp. immaculatus . Also, as visible in the above examples, the Latinised portions of the scientific names of genera and their included species (and infraspecies, where applicable) are, by convention, written in italics . The scientific names of virus species are descriptive, not binomial in form, and may or may not incorporate an indication of their containing genus; for example,

1995-407: The genus Murexia . The interspecific relations of the genus Antechinus are still under review. The currently accepted phylogeny is the presence of four clades within the Antechinus genus. Generally, the clades are formed by species with similar geographic distributions. Clade 1 (dusky antechinus) Clade 2 Clade 3 (brown antechinus) Clade 4 Antechinus are mainly insectivorous , but

2052-426: The increase usually proves fatal. If there were no male die-off, there would still only be a small likelihood of males surviving to the next mating period. Thus, it is far better for the males to invest heavily in one breeding season than attempt to survive to the next one. There are a few possible evolutionary advantages to the evolution of synchronous mating. It may ensure that as many matings as possible occur during

2109-633: The largest component, with 23,236 ± 5,379 accepted genus names, of which 20,845 ± 4,494 are angiosperms (superclass Angiospermae). By comparison, the 2018 annual edition of the Catalogue of Life (estimated >90% complete, for extant species in the main) contains currently 175,363 "accepted" genus names for 1,744,204 living and 59,284 extinct species, also including genus names only (no species) for some groups. The number of species in genera varies considerably among taxonomic groups. For instance, among (non-avian) reptiles , which have about 1180 genera,

2166-722: The leaf litter. The efficiency of Antechinus hunting increases with their age as they learn which prey are the best to eat. Antechinus have been observed scraping slugs on rocks and other objects to remove the mucus and make them more palatable. Antechinus have an extremely unusual reproductive system. The females are synchronously monoestrous with mating occurring over a short three-week period. The males experience mass mortality after mating, with male survival only observed in very rare cases. Females often mate twice or, in some cases, three times during their lives. The gestation period varies by species between 25 and 35 days. The offspring are independent after about 90–100 days, depending on

2223-409: The length of daylight, determines the commencement of the breeding season. Different species respond to different critical rates of change, for example 80% of A. stuartii ovulate when the photoperiod is increasing by a rate of 97-117s/day. The critical rate also varies by location within species. Antechinus live in the relatively stable environments along the east coast of Australia . Responding to

2280-454: The mating period. It also ensures that males can focus all their effort into one short breeding season. Another possible advantage of synchronous mating is to overwhelm predators with large numbers of offspring after weaning. Torpor is periodic lowering of body temperature and metabolic rate to reduce energy consumption. Many marsupials undergo torpor as well as some birds and placental mammals. There are two types of torpor: hibernation which

2337-496: The minimum body temperature during torpor can be around 20 °C (68 °F). In males it is higher, around 30 °C (86 °F). Smaller animals have a lower body temperature during torpor. An increase in the induction of torpor in Antechinus has been found to occur after intense bushfires . Intense bushfires destroy the dense undergrowth that provide Antechinus with shelter and food. After intense bush fires Antechinus were recorded as eating mainly ants, which usually form

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2394-403: The most (>300) have only 1 species, ~360 have between 2 and 4 species, 260 have 5–10 species, ~200 have 11–50 species, and only 27 genera have more than 50 species. However, some insect genera such as the bee genera Lasioglossum and Andrena have over 1000 species each. The largest flowering plant genus, Astragalus , contains over 3,000 species. Which species are assigned to a genus

2451-428: The name could not be used for both. Johann Friedrich Blumenbach published the replacement name Ornithorhynchus in 1800. However, a genus in one kingdom is allowed to bear a scientific name that is in use as a generic name (or the name of a taxon in another rank) in a kingdom that is governed by a different nomenclature code. Names with the same form but applying to different taxa are called "homonyms". Although this

2508-412: The nest. Inbreeding avoidance is likely to explain that behaviour. Male die-off occurs because of an increase in free corticosteroids in the blood, which causes a suppression of the immune system and gastrointestinal ulcers and which result in male mortality. An increase in free corticosteroids is thought to allow males to utilise their reserve energy and maximise their reproductive effort, even though

2565-669: The night is not uncommon. Torpor allows the animals to conserve energy while they are not foraging. The substantial savings in water requirements during torpor may also help Antechinus cope with droughts . Body mass is an important factor for the induction of torpor, with larger animals less likely to go into torpor and more likely to stay in torpor for shorter periods of time. This means that males go into torpor less frequently than females. Lactating females do not go into torpor. Torpor in Antechinus can last for one to nine hours and in extreme cases nearly 20 hours. The body temperatures of these animals drops significantly. In female A. flavipes

2622-422: The photoperiod, rather than temperature or rainfall, allows Antechinus to have young developing before the seasonal increase of food experienced, rather than waiting for the increase of food and possibly missing the window of opportunity. The timing of mating ensures that the offspring are weaning when there is a large amount of food available in the environment. The timing of the increase in food changes throughout

2679-480: The prey available to them However, they do show preference for some prey, i.e. beetles, spiders and larvae, especially when they are not food stressed. The microhabitat and foraging techniques vary between species. Smaller species, such as A. stuartii, are scansorial and mainly hunt in trees. They have been observed jumping between branches to catch flying insects. The larger species of Antechinus , such as A. swainsonii, are completely ground dwelling and forage in

2736-541: The provisions of the ICZN Code, e.g., incorrect original or subsequent spellings, names published only in a thesis, and generic names published after 1930 with no type species indicated. According to "Glossary" section of the zoological Code, suppressed names (per published "Opinions" of the International Commission of Zoological Nomenclature) remain available but cannot be used as the valid name for

2793-548: The rate of change of the photoperiod for reproduction is less certain. That is because in higher latitudes the photoperiod changes much faster. Animals that mate when the photoperiod is changing by 35-90s/day would only have two or three days in Tasmania, compared with two weeks in New South Wales .  Females control the synchrony of mating, with males reproductively mature and ready to mate four or five weeks before

2850-470: The same kind as other (analogous) genera. The term "genus" comes from Latin genus , a noun form cognate with gignere ('to bear; to give birth to'). The Swedish taxonomist Carl Linnaeus popularized its use in his 1753 Species Plantarum , but the French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or

2907-408: The scientific epithet) of a genus is also called the generic name ; in modern style guides and science, it is always capitalised. It plays a fundamental role in binomial nomenclature , the system of naming organisms , where it is combined with the scientific name of a species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in

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2964-445: The species. That development period is rather long compared with other, similarly sized marsupials . The timing of the breeding season differs between species and also with the location of populations. The breeding season is in winter or early spring of the southern hemisphere , from July to September. The timing of the breeding season changes very little at the same location between different years. The rate of change of photoperiod ,

3021-497: The specific name particular to the wolf. A botanical example would be Hibiscus arnottianus , a particular species of the genus Hibiscus native to Hawaii. The specific name is written in lower-case and may be followed by subspecies names in zoology or a variety of infraspecific names in botany . When the generic name is already known from context, it may be shortened to its initial letter, for example, C. lupus in place of Canis lupus . Where species are further subdivided,

3078-412: The standard format for a species name comprises the generic name, indicating the genus to which the species belongs, followed by the specific epithet, which (within that genus) is unique to the species. For example, the gray wolf 's scientific name is Canis lupus , with Canis ( Latin for 'dog') being the generic name shared by the wolf's close relatives and lupus (Latin for 'wolf') being

3135-403: The taxon is termed a synonym ; some authors also include unavailable names in lists of synonyms as well as available names, such as misspellings, names previously published without fulfilling all of the requirements of the relevant nomenclatural code, and rejected or suppressed names. A particular genus name may have zero to many synonyms, the latter case generally if the genus has been known for

3192-576: The values quoted are the mean of "accepted" names alone (all "uncertain" names treated as unaccepted) and "accepted + uncertain" names (all "uncertain" names treated as accepted), with the associated range of uncertainty indicating these two extremes. Within Animalia, the largest phylum is Arthropoda , with 151,697 ± 33,160 accepted genus names, of which 114,387 ± 27,654 are insects (class Insecta). Within Plantae, Tracheophyta (vascular plants) make up

3249-429: The virus species " Salmonid herpesvirus 1 ", " Salmonid herpesvirus 2 " and " Salmonid herpesvirus 3 " are all within the genus Salmonivirus ; however, the genus to which the species with the formal names " Everglades virus " and " Ross River virus " are assigned is Alphavirus . As with scientific names at other ranks, in all groups other than viruses, names of genera may be cited with their authorities, typically in

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