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46-414: Bipalium is a genus of large predatory land planarians . They are often loosely called " hammerhead worms " or " broadhead planarians " because of the distinctive shape of their head region. Land planarians are unique in that they possess a "creeping sole", a highly ciliated region on the ventral epidermis that helps them to creep over the substrate. Native to Asia, several species are invasive to

92-403: A darker color than the background color of the dorsum and lacks stripes. The ventral side has a light ochre color externally and whitish over the creeping sole, which is externally lined by two diffuse grey-violet longitudinal lines. Bipalium kewense is believed to be native to Southeast Asia , but currently is found worldwide. It has been reported on every continent aside from Antarctica. It

138-643: 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

184-621: 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,

230-453: A primary means of reproduction. Asexual fragmentation is the primary means of reproduction in B. kewense in temperate regions. Long specimens usually release body fragments at the posterior end by transverse fission. The fragments are motile and regenerate the head plate and pharynx in a few weeks. Such a reproduction strategy is considered one reason for the successful colonization of this and other species of Bipalium . Although there

276-410: A primary method of reproduction. Asexual fragmentation is its main reproductive strategy in temperate regions and most individuals never develop sexual organs. Juveniles of this species, unlike B. adventitium , do not appear the same coloration as parents in their early days. In 2014, the presence of tetrodotoxin , a very dangerous neurotoxin , was recorded in B. adventitium and B. kewense . It

322-409: 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

368-677: A single dark dorsal stripe. They were first discovered in the US in California and New York but have been found in Illinois as well as most northern states. In 2019, they were discovered in Montreal, Canada. B. kewense have five dark dorsal stripes and a partial dark collar. They have undergone several name changes since their discovery in North America. B. kewense is commonly found across the southern regions of

414-427: 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. ;

460-455: 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

506-458: Is also used to refer to other species in the subfamily Bipaliinae . Bipalium kewense is a very long land planarian. Preserved specimens are up to 20 centimetres in length, and living specimens may be longer. The anterior end ("head") is expanded in a transversal semilunate shape and the body is the narrowest just behind the head, in a region called "neck". The dorsal color is light-brown with five black to grey longitudinal stripes that begin at

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552-596: 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

598-778: Is little evidence of sexual reproduction in these planarians, there have been several reported cases of egg capsules being discovered. The egg capsules discovered had several of the same characteristics of those of B. adventitium , including coloration and incubation period. The most recent egg capsule discovered hatched offspring that did not bear a complete resemblance to adults and were considerably larger in size to that of B. adventitum offspring. A 2018 study showed that sequences of Cytochrome c oxidase subunit I (a mitochondrial gene commonly used for barcoding ) were identical for all specimens from various countries originating from several continents, suggesting that specimens were clonal. The complete mitochondrial genome , 15,666-bp in length,

644-460: 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,

690-474: 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

736-613: Is the first record of tetrodotoxin in terrestrial invertebrates. Little is known about the ecology of terrestrial planarians, but research has been done on different genera and species, including several native and invasive species in Brazil, Arthurdendyus triangulatus , Rhynchodemus and Bipalium . As of 2007, four invasive species of Bipalium were known in the United States: B. adventitium , B. kewense , B. pennsylvanicum , and B. vagum . These planarians are thought to have come to

782-621: 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

828-799: 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;

874-419: 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 ,

920-404: 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,

966-843: The US on infected plants and soil. Bipalium kewense has been found commonly in American greenhouses since 1901. This species is a voracious predator of earthworms, and has been identified as a nuisance in the southern USA in earthworm-rearing beds. Control of the species is difficult due to the lack of predators. As noted by the University of Florida IFAS department, Other animals rarely devour land planarians, since surface secretions appear distasteful, if not toxic. Protozoans, including flagellates, ciliates, sporozoans, and nematodes have been detected in land planarians. Because of their cannibalistic habit, land planarians may be their own worst enemy. Specimens of Bipalium adventitium are characterized by

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1012-604: The US. B. kewense is found worldwide in tropical and subtropical regions. Bipalium pennsylvanicum is characterized by its dark brown head and three dorsal stripes. As of 2014, it has only been found in Pennsylvania and in coastal South Carolina . Bipalium vagum is characterized by two dark dorsal blotches on the head, a thick black band around the neck, and three dark dorsal stripes. This species has been found in several Gulf Coast states, and in 2022, specimens were located extending further north into Arkansas . Recently, it

1058-539: The United States, Canada, and Europe. Some studies have begun the investigation of the evolutionary ecology of these invasive planarians. The name Bipalium comes from Latin bi- , "two" + pala , "shovel" or "spade", because species in this genus resemble a pickaxe . The genus Bipalium was initially defined by Stimpson to include land planarians with the head broadened, forming a head plate. Later, in 1899, Ludwig von Graff divided it into three genera according to

1104-448: The attack, but the flatworm uses the muscles in its body, as well as sticky secretions, to attach itself to the earthworm to prevent escape. The planarians cover, or cap, the prostomium , peristomium , and anterior end to stop the violent reaction by the earthworm. To feed on their prey, species of Bipalium often evert their pharynges from their mouths, located on the midventral portion of their bodies, and secrete enzymes that begin

1150-442: 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

1196-519: The digestion of the prey. The liquefied tissues are sucked into the branching gut of the flatworms by ciliary action. Reproduction in Bipalium may be asexual or sexual and all species are hermaphroditic . B. adventitium reproduces sexually and creates egg capsules, which hatch around 3 weeks post-deposition. The egg capsules have a tough exterior and generally contain multiple juveniles. B. kewense have rarely been observed using egg capsules as

1242-532: The earthworm's body and beginning digestion. The digestion seems to be at least partially extracorporeal by means of a collagenolytic enzyme . Bipalium kewense is one of the few terrestrial invertebrates known to produce tetrodotoxin , a neurotoxin that results in paralysis. It is possible that the toxin aids the planarian in subduing its prey as well as in protecting it against predators. All species of Bipalium are hermaphroditic, but Bipalium kewense has rarely been observed using sexual reproduction as

1288-446: 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

1334-727: 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,

1380-621: The genus Bipalium , but later split them into four genera based on the anatomy of the reproductive organs : Bipalium , Novibipalium , Humbertium , and Diversibipalium . Under this scenario, the genus Bipalium is defined as containing broad-headed land planarians with simple copulatory organs, without accessory ducts or copulatory bursa, and with a fold of tissue separating the male and female exit ducts. Bipalium species are predatory . Some species prey on earthworms , while others may also feed on mollusks . These flatworms can track their prey. When captured, earthworms begin to react to

1426-628: 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,

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1472-461: The lizard genus Anolis has been suggested to be broken down into 8 or so different genera which would bring its ~400 species to smaller, more manageable subsets. Bipalium kewense Bipalium kewense , also known as the shovel-headed garden worm , is a species of large predatory land planarian with a cosmopolitan distribution . It is sometimes referred to as a "hammerhead flatworm" due to its half-moon-shaped head, but this name

1518-403: 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

1564-428: 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

1610-417: The neck. The median and marginal stripes are narrow and black, very distinctly marked. The lateral stripes (between the median and marginal stripes) are usually grey, broad and with diffuse margins. The neck is usually marked by an incomplete black collar formed by the union of the marginal and lateral stripes, this being one of the main characteristics to distinguish it from similar species. The head usually has

1656-526: 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

1702-466: 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

1748-408: 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

1794-511: The shape of the head: Josef Müller , in 1902, considered that no sufficient anatomical basis existed for this distinction, and reunited them under Bipalium . Later, von Graff accepted Müller's conclusions. Towards the end of the 20th century, Robert E. Ogren and Masaharu Kawakatsu started a series of publications called "The Land Planarian Index series" in which they reviewed and organized all taxonomic information regarding land planarians. At first, they retained all broad-headed planarians in

1840-497: 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,

1886-412: 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

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1932-403: 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

1978-566: 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

2024-429: 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

2070-586: Was found in Mumbai, India. The genus Bipalium currently includes the following species: 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

2116-548: Was probably introduced by international plant trade, as it is frequently found associated with plant pots. The species was first found in 1878 in the area of the Kew Park in the London Borough of Richmond upon Thames , United Kingdom , hence the name kewense . B. kewense is a known predator of earthworms . It immobilizes the prey using muscular movements and possibly toxins and then everts its pharynx , connecting it to

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