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63-396: Phrynosoma , whose members are known as the horned lizards , horny toads , or horntoads , is a genus of North American lizards and the type genus of the family Phrynosomatidae . Their common names refer directly to their horns or to their flattened, rounded bodies, and blunt snouts. The generic name Phrynosoma means "toad-bodied". In common with true toads ( amphibians of

126-506: A blood plasma factor that neutralizes harvester ant venom and are known to produce copious amounts of mucus in the esophagus and pharynx which function to embed and incapacitate swallowed ants. In recent years, the species has declined by about 30% of its range, though it may be making a comeback. The decline is usually blamed on overuse of pesticides and the spread of nonnative, highly aggressive and fiercely territorial red imported fire ants . Both eradicate harvester ant colonies, destroying

189-467: A carnival and parade. 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

252-556: A chemical that is foul-tasting to canine predators such as wolves , coyotes , and domestic dogs. This novel behavior is generally observed to be very effective in defense; however, it appears to have no effect against predatory birds . They can lose up to 6 percent of their body weight when performing this. About 70% of the Texas horned lizard's diet is made up of harvester ants , though they supplement these with termites , beetles , and grasshoppers . Texas horned lizards possess

315-651: 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

378-628: 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,

441-429: A number of factors, including the fragmentation and loss of habitat from real estate development and road construction, the planting of non-native grasses (both suburban and rural), conversion of native land to pastureland and agricultural uses, and pesticides. Additionally predation by domestic dogs and cats place continued pressure upon horned lizards. Fire ants ( Solenopsis invicta ), introduced from South America via

504-409: 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

567-427: 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. ;

630-455: 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

693-615: Is absent. Of the 21 species of horned lizards, 15 are native to the USA. The largest-bodied and most widely distributed of the American species is the Texas horned lizard . Horned lizards use a variety of means to avoid predation . Their coloration generally serves as camouflage . When threatened, their first defense is to remain motionless to avoid detection. If approached too closely, they generally run in short bursts and stop abruptly to confuse

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756-483: Is averaged at 50 m (160 ft). They hibernate in burrows averaging in depth at 140 mm (5.5 in) and often have them face south/southwest for maximum sun exposure. Although its coloration generally serves as camouflage against predation, when threatened by a predator , a horned lizard puffs up and appears very fat, which causes its body scales to protrude, making it difficult to swallow. The Texas horned lizard, along with at least three other species of

819-612: 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

882-626: Is funded by sale of horned lizard "Keep Texas Wild" license plates. In addition, the Dallas Zoo and Houston Zoo are working to establish a captive colony of animals with several key reproductive successes taking place in 2015. Some Native American people regard horned lizards as sacred. The animal is a common motif in Native American art in the Southwestern United States and Mexico. The Texas horned lizard

945-551: Is known from barrier islands on the Gulf Coast of Texas and Tamaulipas at sea level, up to about 1,830 meters elevation. It is absent for higher elevations within its range, where other species of the genus may occur (e.g. Sierra Madre Oriental ). Ecological associations include the southern Great Plains , Edwards Plateau , Tamaulipan mezquital , Chihuahua Desert , Llanos el Salado , and many peripheral and marginal areas of these ecoregions. The eastern distributional limit of

1008-541: Is listed as a threatened species in the state, it is illegal to pick up, touch, or possess them in Texas. The horned lizard is popularly called a "horned toad", "horny toad", or "horned frog", but it is neither a toad nor a frog . The popular names come from the lizard 's rounded body and blunt snout, which give it a decidedly batrachian appearance. Phrynosoma literally means "toad-bodied" and cornutum means "horned". The lizard 's horns are extensions of its cranium and contain true bone . The Texas horned lizard

1071-460: 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,

1134-474: 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

1197-410: Is the largest-bodied and most widely distributed of the roughly 21 species of horned lizards in the western United States and Mexico. The Texas horned lizard exhibits sexual dimorphism, with the females being larger with a snout-vent length of around 5 in (13 cm), whereas the males reach around 3.7 in (9.4 cm). "Phrynosoma cornutum" has characteristic horns spanning across its body with

1260-778: Is the “Horn Toad”, the greater short-horned lizard ( Phrynosoma hernandesi ). The " TCU Horned Frog " is the mascot of Texas Christian University in Fort Worth, Texas. The "Horned Toad" is also the mascot for Coalinga High School in Coalinga, California. This school is located in Western Central California and its arid region is home to the San Diego Horned Lizard, which is protected. The City of Coalinga hosts an annual "Horned Toad Derby" on Memorial day weekend which features horned toad races,

1323-567: The Fort Worth Zoo . Hatchlings are bred and released in targeted areas in the hope that with a large number of animals, enough will survive to grow the population in the wild. Typically in such reptile reintroduction programs, fewer than one percent of a female's offspring will survive in the wild to adulthood. Horned lizards are studied by researchers at Texas Christian University , the nearby Fort Worth Zoo , and Dallas Zoo with raw data and fieldwork done by state employees. Since 2010,

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1386-621: 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

1449-824: 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;

1512-473: The Reptile Database , three species of which have recognized subspecies : Note : In the above list, a binomial authority or trinomial authority in parentheses indicates that the species or subspecies was originally described in a genus other than Phrynosoma . Texas designated the Texas horned lizard ( Phrynosoma cornutum ) as the official state reptile in 1993. Wyoming’s state reptile

1575-419: 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 ,

1638-404: 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,

1701-649: The Dallas Zoo has been conducting a mark-and-recapture study on Texas horned lizards on the Rolling Plains Quail Research Ranch, a 4,700 acres (19 km ) preserve located in Fisher County, Texas. Dallas Zoo researchers capture animals, tag them, collect data, and release them. The project's goals are aimed at shedding light on the life history, population density, and determining ecological conditions best suited for this threatened species. Further research toward their preservation

1764-473: The Texas horned lizard in the piney woods region of east Texas and western Louisiana , and the Ozark Mountain forests of western Arkansas , and Missouri likely represent introductions however, some have argued these records reflect natural relic populations . Many records of introductions from areas beyond its natural range have been reported as a result of released and escaped individuals from

1827-461: The US and northeastern Mexico, as well as several isolated introduced records and populations from Southern United States . Though some populations are stable, severe population declines have occurred in many areas of Texas and Oklahoma. The Texas spiny lizard ( Sceloporus olivaceus ) may be confused for a Texas horned lizard due to its appearance and overlapping habitat. Because the Texas horned lizard

1890-588: The ant populations upon which the lizards prey, displacement of native ant populations by invading fire ants (aided by synergistic effects of native ant eradication), and predation by domestic dogs and cats. In 2014, the Center for Biological Diversity in Tucson, Arizona petitioned the Oklahoma Department of Wildlife Conservation to have the Texas horned lizard put on the endangered species list due to

1953-442: 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

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2016-501: The blood flow leaving the head, thereby increasing blood pressure and rupturing tiny vessels around the eyelids . The blood not only confuses predators but also tastes foul to canine and feline predators. It appears to have no effect against predatory birds . Only three closely related species ( P. mcallii , P. modestum , and P. platyrhinos ) are certainly known to either be unable to squirt blood or only do it extremely rarely. While previous thought held that compounds were added to

2079-434: The blood from glands in the ocular sinus cavity, current research has shown that the chemical compounds that make up the defense are already in the circulating blood. It is possible that their diet of large quantities of venomous harvester ants could be a factor; however, the origin and structure of the chemicals responsible are still unknown. The blood-squirting mechanism increases survival after contact with canine predators;

2142-595: The collected lizards. In 1967, the state of Texas passed protective legislation preventing the collection, exportation, and sale of Phrynosoma , and by the early 1970s, most states enacted similar laws to protect and conserve horned lizards in the USA. As recently as the early 2000s, though, the state of Nevada still allowed commercial sale of Phrynosoma species. Despite limited federal protection in Mexico , horned lizards are still offered in Mexican "pet" markets throughout

2205-665: The country. In 2014, the Center for Biological Diversity in Tucson petitioned the Oklahoma Department of Wildlife Conservation to have the Texas horned lizard put on the endangered species list due to the massive decline of its population in Oklahoma, where it was once plentiful. The center said it may later seek protection for the animal on a federal level; it also said that reptiles in general are dying off at up to 10,000 times their historic extinction rate, greatly due to human influences. The following 21 species (listed alphabetically by scientific name) are recognized as being valid by

2268-713: The eyes to the tip of the horns and a characteristic solid white line with a few black circular splotches on either side. The Texas horned lizard, like all members of the genus Phrynosoma , is endemic to North America where it occurs in south-central regions of the US and northeastern Mexico. Its natural distribution includes southeast Colorado , central and southern areas of Kansas , central and western areas of Oklahoma and Texas , southeast New Mexico , and extreme southeast Arizona . In Mexico it occurs in extreme eastern Sonora , most of Chihuahua , northeast Durango , northern Zacatecas and San Luis Potosí , and throughout most of Coahuila , Nuevo León , and Tamaulipas . It

2331-418: The family Bufonidae ), horned lizards tend to move sluggishly, often remain motionless, and rely on their remarkable camouflage to avoid detection by predators. They are adapted to arid or semiarid areas. The spines on the lizard's back and sides are modified reptile scales , which prevent water loss through the skin, whereas the horns on the head are true horns (i.e., they have a bony core). A urinary bladder

2394-418: The fierce appearance, Texas horned lizards are extremely docile creatures. The Texas horned lizard is a sunbather, and requires bright sunlight to produce vitamin D . Deprived of sunlight, the animal is unable to produce vitamin D and can suffer from vitamin deficiency. So, horned lizards are most often found along the side of roads or other open, rocky areas, where they can lounge and take in sunlight. At night,

2457-446: 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

2520-737: 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,

2583-405: The genus Phrynosoma , also has the ability to squirt an aimed stream of blood from the corners of the eyes and sometimes from its mouth at a distance up to 5 ft (1.5 m). They do this by restricting the blood flow leaving the head, thereby increasing blood pressure and rupturing tiny vessels around the eyelids . This not only confuses would-be predators, but also the blood is mixed with

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2646-474: The head or neck, a horned lizard ducks or elevates its head and orients its cranial horns straight up, or back. If a predator tries to take it by the body, the lizard drives that side of its body down into the ground so the predator cannot easily get its lower jaw underneath. A University of Texas publication notes that horned lizard populations continue to disappear throughout their distribution despite protective legislation. Population declines are attributed to

2709-633: 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,

2772-417: The lizard buries itself in sand. Although they prefer to move very little, horned lizards can move quite fast if they feel a predator is in the area, and dart into thick grass and foliage to escape. Horned lizards are also excellent diggers, and can quickly burrow underground to escape threats. Horned lizards are often found near harvester ant colonies which are a major part of their diet. Their daily movement

2835-431: 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. Phrynosoma cornutum The Texas horned lizard ( Phrynosoma cornutum ) is one of about 21 North American species of spikey-bodied reptiles called horned lizards , all belonging the genus Phrynosoma . It occurs in south-central regions of

2898-496: The lizard's principal source of food. The Texas horned lizard is now a protected species, and, in Texas, it is illegal to take, possess, transport or sell them without a special permit. A University of Texas publication notes that horned lizard populations continue to disappear throughout the southwest despite protective legislation. The Texas horned lizard has disappeared from almost half of its geographic range. Population declines are attributed to loss of habitat, human eradication of

2961-415: The massive decline of its population in Oklahoma, where it was once plentiful. The Center said it may later seek protection for the animal on a Federal level; it also said that reptiles in general are dying off at up to 10,000 times their historic extinction rate, greatly due to human influences. In Texas, the creature has been declared threatened and a breeding and reintroduction program has been started by

3024-403: 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

3087-428: 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

3150-552: The native species on which the lizards prey, contribute to the continued displacement of native ant species and the decline of horned lizards. The Texas horned lizard ( Phrynosoma cornutum ) has disappeared from almost half of its geographic range. Their popularity in the early to mid-20th-century pet trade, where collectors took thousands from the wild populations to sell to pet distributors, without provision for their highly specialized nutritional needs (primarily formic acid from harvester ants), resulted in certain death for almost all

3213-442: The nursery industry's potted plants, pose a significant threat to all wildlife including horned lizards. Phrynosoma species do not eat fire ants. Fire ants kill many species of wildlife, and are fierce competitors against the native ants, which horned lizards require for food (with their specialized nutritional content). Fire ants have given all ants a bad reputation, and human attempts to eradicate ants, including invasive species and

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3276-621: The pet trade in the early and mid-twentieth century, including: Alabama , Arizona, Colorado , the District of Columbia , Illinois , Indiana , Kentucky , Michigan , Mississippi , Nebraska , North Carolina , Tennessee , Virginia , and Wyoming , although these do not represent established, breeding populations. However, a few stable populations, some known for over 50 years, occur in Florida , Georgia , and South Carolina , but these do not seem to be dispersing or spreading. Despite

3339-461: The predator's visual acuity. If this fails, they puff up their bodies to cause them to appear more horned and larger so that they are more difficult to swallow. At least eight species ( P. asio , P. cornutum , P. coronatum , P. ditmarsi , P. hernandesi , P. orbiculare , P. solare , and P. taurus ) are also able to squirt an aimed stream of blood from the corners of the eyes for a distance up to 5 ft (1.5 m). They do this by restricting

3402-541: 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

3465-470: 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

3528-408: 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

3591-497: 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,

3654-412: 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

3717-403: 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

3780-416: The trait may provide an evolutionary advantage. Ocular autohemorrhaging has also been documented in other lizards, which suggests blood-squirting could have evolved from a less extreme defense in the ancestral branch of the genus. Recent phylogenic research supports this claim, so the species incapable of squirting blood apparently have lost the adaptation for reasons yet unstudied. To avoid being picked up by

3843-400: The two largest crowning its head, two more on its brows and jawline respectively, as well as lines of spikes spanning the lateral parts of torso and dorsal ridges of the back. Coloration varies depending on the environment in order to blend in with the color of the ground, ranging from a yellow or reddish-brown for deserts to a tannish brown for prairies. They also have dark lines that span from

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3906-576: 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

3969-429: 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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