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52-452: Apororhynchus is a genus of small parasitic spiny-headed (or thorny-headed) worms. It is the only genus in the family Apororhynchidae , which in turn is the only member of the order Apororhynchida . A lack of features commonly found in the phylum Acanthocephala (primarily musculature) suggests an evolutionary branching from the other three orders of class Archiacanthocephala ; however no genetic analysis has been completed to determine

104-557: A species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in 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 ,

156-651: 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

208-628: 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,

260-486: A member of the Zoological Society of India . It parasitizes the spotted owlet ( Athene brama ) and has been found in the intestine. The body is 4.70 mm by 1.70 mm long with a proboscis that is 1.11 mm by 1.68 mm in length and immature eggs are around 0.015 mm to 0.035 mm in diameter. The hooks on the proboscis are finger shaped and numerous, especially in the posterior. The rest of

312-484: A proboscis wider than the anterior part of the trunk, with about 40 spiral rows of hooks, each row bearing 14 to 16 hooks. There are 28 to 31 giant nuclei in the body wall and 9 to 12 in the lemnisci. The testes are almost parallel. The parasite has been found infesting juvenile European robins, indicating that the infestation occurred in the nesting area. The life cycle of an acanthocephalan consists of three stages beginning when an infective acanthor (development of an egg)

364-409: 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

416-427: 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. ;

468-455: 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

520-431: A unique order in the class Archiacanthocephala . The lack of morphological features such as an absence of a muscle plate, a midventral longitudinal muscle, lateral receptacle flexors, and an apical sensory organ when compared to the other three orders of class Archiacanthocephala indicate it is an early offshoot ( basal ). The genus Apororhynchus consists of ectoparasitic worms that attach themselves beneath

572-612: 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

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624-413: Is released from the intestines of the definitive host and then ingested by an arthropod, the intermediate host . The intermediate hosts of Apororhynchus are not known. When the acanthor molts , the second stage called the acanthella begins. This stage involves penetrating the wall of the mesenteron or the intestine of the intermediate host and growing. The final stage is the infective cystacanth which

676-460: 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,

728-704: Is the larval or juvenile state of an Acanthocephalan, differing from the adult only in size and stage of sexual development. The cystacanths within the intermediate hosts are consumed by the definitive host, usually attaching to the walls of the intestines, and as adults they reproduce sexually in the intestines. The acanthor are passed in the feces of the definitive host and the cycle repeats. There are no known paratenic hosts (hosts where parasites infest but do not undergo larval development or sexual reproduction) for Apororhynchus . Apororhynchus species exclusively parasitize avian hosts of different orders including owls , waders , and passerines . The parasite attaches to

780-474: 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

832-621: 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

884-824: 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;

936-398: The cloaca using their hook-covered proboscis . The bird hosts are of different orders, including owls , waders , and passerines . Infestation by an Apororhynchus species may cause enteritis and anemia . The first species in this order to be described was Apororhynchus hemignathi which was originally named Arhynchus hemignathi by Arthur Shipley in 1896. The name Arhynchus

988-460: The eversion of the proboscis. Additional anatomical features that can be used to distinguish this genus among other acanthocephalans include a cerebral ganglion located under the anterior wall of the proboscis, long and tubular lemnisci (bundles of sensory nerve fibers) that run along a central canal, the lack of any protonephridia (an organ which functions as a kidney), and the presence of eight pear-shaped cement glands used to temporarily close

1040-404: 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,

1092-650: The European robin in Alsóperepuszta , Hungary. Described in 1980, it is the most recently classified species of the Apororhynchus . A. silesiacus is named after Silesia , a region in Poland where the parasite was found. Specimens were between 3.21 and 3.51 mm in total length, with a maximum width of 0.80 to 1.05 mm at middle and the eggs were around 0.07 mm long and 0.035 mm wide. It has

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1144-473: The French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or 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

1196-442: 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

1248-461: The body, there are 10–16 giant nuclei with a diameter of 0.050–0.077 mm. There is a very short neck (0.153 mm long) between the proboscis and the body with attached ribbon-like lemnisci longer than their own body length. Females are 3.7 mm long by 0.92 mm in maximum width and the proboscis is 1.30 mm long by 1.53 mm in maximum width. The male is smaller being 3.21 mm long by 0.766 mm in maximum width and

1300-670: The cloaca and in some cases the intestinal wall using a hook-covered proboscis. Infestation can cause enteritis and anemia in Hawaiian honeycreepers . There are no reported cases of any Apororhynchus species infesting humans in the English language medical literature. 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

1352-652: The colon and cloaca of the Eastern yellow wagtail ( Motacilla tschutschensis ) in Chukotka and Kamchatka (including the Karaginsky Island ), also in Russia . It was described in 1966. The proboscis is large compared to the body and spherical. It is armed with 10–12 spiral rows of hooks with 14–15 hooks in each row. The hook has a thin blade with a curved tip and root thickened with broadened base. In

1404-421: The digestive tract, just inside the vent. The species name amphistomi derives from a superficial resemblance to the amphistomate trematodes (flukes with stoma on opposite sides). On the proboscis, there are approximately 20 very fine hooks found on each of 40 rows. The two lemnisci are longer than the body length and are folded in the body cavity. Females are 2.13 mm long by 0.83 mm in maximum width and

1456-591: The evolutionary relationship between species. The distinguishing features of this order among archiacanthocephalans is a highly enlarged proboscis which contain small hooks. The musculature around the proboscis (the proboscis receptacle and receptacle protrusor) is also structured differently in this order. This genus contains six species that are distributed globally, being collected sporadically in Hawaii, Europe, North America, South America, and Asia. These worms exclusively parasitize birds by attaching themselves around

1508-446: 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

1560-737: 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,

1612-517: The hooks on the anterior side are irregularly directed and sparse. The proboscis sheath is absent. The nerve ganglion is large and located near the anterior proboscis. The lemnisci are very long and unequal. A. hemignathi was the first species of Apororhynchus to be described with the creation of the genus and family by Arthur Shipley in 1896 due to its uniqueness among already described Acanthocephala. It has been found in Kaua'i , Hawaii , parasitizing

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1664-432: 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 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

1716-633: 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,

1768-435: 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. Lemniscus (anatomy) A lemniscus ( Greek for ribbon or band ) is a bundle of secondary sensory fibers in the brainstem . The medial lemniscus and lateral lemniscus terminate in specific relay nuclei of the diencephalon . The trigeminal lemniscus

1820-403: 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

1872-428: 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

1924-538: The now extinct Kauaʻi ʻakialoa ( Akialoa stejnegeri ). A. hemignathi was named after the genus of the Kauaʻi ʻakialoa, which was Hemignathus at the time of the description. Specimens range from 2.5 mm to 3.5 mm long, distended 1 mm to 1.5 mm longer. It has two to four nuclei in the lemnisci. It is the type species for the genus. This parasite has been found in the black-winged pratincole ( Glareola nordmanni ) at Malye Chany Lake , in Russia , and in

1976-474: The posterior end of the female after copulation. There are six species in the genus Apororhynchus . A seventh species, Apororhynchus bivolucrus Das, 1950 (also called A. bivolucrus ) from an Egyptian vulture ( Neophron percnopterus ) from India was considered to be a strigeid trematode by Yamaguti (1963). A. aculeatus has been found in Santos , Brazil, parasitizing a New World oriole . The parasite

2028-461: The proboscis is 0.36 mm long by 0.44 mm in maximum width. The male is smaller being 1.43 mm long by 0.53 mm in maximum width and the proboscis is 0.44 mm long by 0.74 mm in maximum width. A. chauhani is the only Apororhynchus species described from India. It was discovered in Srisailam , Andhra Pradesh, in 1975. A. chauhani was named after Birendra Singh Chauhan,

2080-533: The proboscis is 0.796 mm long by 0.995 mm in maximum width. The eggs were oval shaped with three concentric shells around 0.074–0.080 mm long and 0.040–0.043 mm wide. A. silesiacus was found in the cloaca of the European robin ( Erithacus rubecula ), the thrush nightingale ( Luscinia luscinia ) and the common nightingale ( Luscinia megarhynchos ) in Wroclaw , Poland, and of

2132-423: The proboscis wall. Two regions of musculature are considerably different in Apororhynchus compared to the other acanthocephalan orders: the proboscis receptacle and receptacle protrusor are both reorganized in Apororhynchus with the muscles subdivided into strands extending from the cerebral ganglion , or nerve bundle, to the proboscis wall. These two muscles suspend the cerebral ganglion but are not involved in

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2184-541: 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

2236-403: The skin and around the anus of birds. The distinguishing features of this order among acanthocephalans are a highly enlarged proboscis with limited motility and a reduced size of the hooks (or spines). Apororhynchus species have short conical trunks and a reduced or absent neck. The proboscis is large and globular with numerous deeply set spirally arranged rootless hooks usually not reaching

2288-497: 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,

2340-412: 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

2392-423: The surface, or with no hooks. They contain sets of muscles that are common to all Acanthocephala including a proboscis receptacle, a receptacle-surrounding muscle called a receptacle protrusor, retinacula (connective tissue that stabilizes tendons), a neck retractor, proboscis and receptacle retractors, circular and longitudinal musculature under the metasomal (trunk) tegument , and a single muscular layer beneath

2444-403: 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

2496-576: 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

2548-429: 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

2600-453: Was chosen based on the characteristic absence of a proboscis in this species of Acanthocephala. It was later renamed Apororhynchus (along with the family name Apororhynchidae) by Shipley in 1899 due to the name Arhynchus having been used by Dujean in 1834 for a beetle. The National Center for Biotechnology Information does not indicate that any phylogenetic analysis has been published on Apororhynchida that would confirm its position as

2652-534: Was discovered in 1931, in the Berlin Museum, taken from the digestive tube of a bird named at that time as " Oriolus cristatus ", which was likely a crested oropendola ( Psarocolius decumanus ). A. aculeatus was the second parasite to be discovered in its genus, and the specimen used to describe the species was female. Numerous fine hooks on the bulb-shaped proboscis, as well as the different host and location, distinguish it from A. hemignathi . The parasite

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2704-588: Was discovered in the summer of 1947 infesting a Canada warbler ( Cardellina canadensis formerly Wilsonia canadensis ) in Mountain Lake, Virginia , and a Northern parula ( Setophaga americana formerly Compsothlyphis americana ) in Augusta, Georgia , thus making it the third species in its genus to be discovered, and the first species in its genus to be discovered in North America. It was found in

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