parent_taxon velafrons
___MASK32___ is a clade of herbivorous dinosaurs that lived from the Middle Jurassic to Late Cretaceous . Some members include " Camptosaurus ", " Callovosaurus ", " Iguanodon ", " Tenontosaurus ", and the hadrosaurids or " duck - billed dinosaurs ". Iguanodontians were one of the first groups of dinosaurs to be found . They are among the best known of the dinosaurs , and were among the most diverse and widespread herbivorous ___MASK71___ groups of the Cretaceous period . Derived iguanodontians ( such as " Muttaburrasaurus " and many ankylopollexians ) were generally large animals , and some ( such as " Shantungosaurus ", which measured up to 50 ft ( 15 m ) in length and weighed up to 8 tons ) equaled the largest carnivorous dinosaurs in size . Saurolophus ( meaning " ___MASK86___ crest ") is a genus of large saurolophine hadrosaurid dinosaurs that lived about 70 . 0  68 . 5 million years ago , in the Late Cretaceous of North America and Asia ; it is one of the few genera of dinosaurs known from multiple continents . It is distinguished by a spike - like crest which projects up and back from the skull . " Saurolophus " was a herbivorous dinosaur which could move about either bipedally or quadrupedally . Hadrosaurids (" hadrós ", " stout , thick "), or duck - billed dinosaurs , are members of the ornithischian family Hadrosauridae . This group is also known as the duck - billed dinosaurs , for the flat , duck - bill appearance of their mouths . The family , which includes ornithopods such as " ___MASK36___ " and " Parasaurolophus ", was a common herbivore in the Upper Cretaceous Period of what is now Asia , Europe , Antarctica , South America and North America . Hadrosaurids are descendants of the Upper Jurassic / Lower Cretaceous iguanodontian dinosaurs and had a similar body layout . Like the rest of the ornithischians , these animals had a predentary bone and a pubic bone which was positioned backwards in the pelvis . Hadrosaurids are divided into two principal subfamilies : the lambeosaurines (" ___MASK72___ "), which had hollow cranial crests or tubes , and the saurolophines , identified as hadrosaurines in most pre - 2010 works (" Saurolophinae " or " Hadrosaurinae "), which lacked hollow cranial crests ( solid crests were present in some forms ). Saurolophines tended to be bulkier than lambeosaurines . Lambeosaurines are divided into Aralosaurines , Lambeosaurines , Parasaurolophines and Tsintaosaurines , while Saurolophines include Saurolophus , Brachylophosaurines and Kritosaurines . The Santonian is an age in the geologic timescale or a chronostratigraphic stage . It is a subdivision of the Late Cretaceous epoch or Upper Cretaceous series . It spans the time between 86 . 3 ± 0 . 7 ___MASK54___ ( million years ago ) and 83 . 6 ± 0 . 7 ___MASK54___ . The Santonian is preceded by the Coniacian and is followed by the Campanian . The Gulf of Mexico is an ocean basin largely surrounded by the North American continent . It is bounded on the northeast , north and northwest by the Gulf Coast of the United States , on the southwest and south by Mexico , and on the southeast by Cuba . The U . S . states of ___MASK40___ , Florida , Louisiana , Mississippi and Texas border the Gulf on the north , which are often referred to as the " Third Coast " in comparison with the U . S . Atlantic and Pacific coasts , or sometimes the " south coast ", in juxtaposition to the Great Lakes region being the " north coast ." One of the gulf ' s seven main ___MASK95___ is the Gulf of Mexico basin . The Campanian is , in the ICS ' geologic timescale , the fifth of six ages of the Late Cretaceous epoch ( or , in chronostratigraphy : the fifth of six stages in the Upper Cretaceous series ). The Campanian spans the time from 83 . 6 ± 0 . 7 Ma to 72 . 1 ± 0 . 6 Ma ( million years ago ). It is preceded by the Santonian and it is followed by the Maastrichtian . The Jurassic ( from Jura Mountains ) is a geologic period and system that spans 56 . 3 million years from the end of the Triassic Period million years ago ( ___MASK54___ ) to the beginning of the Cretaceous Period ___MASK54___ . The Jurassic constitutes the middle period of the Mesozoic Era , also known as the Age of Reptiles . The start of the period is marked by the major Triassic  Jurassic extinction event . Two other extinction events occurred during the period : the Pliensbachian / Toarcian event in the Early Jurassic , and the Tithonian event at the end ; however , neither event ranks among the " Big Five " mass extinctions . A genus ( genera ) is a taxonomic rank used in the biological classification of living and fossil organisms in biology . In the hierarchy of biological classification , genus comes above species and below family . In binomial nomenclature , the genus name forms the first part of the binomial species name for each species within the genus . Asia is Earth ' s largest and most populous continent , located primarily in the eastern and northern hemispheres and sharing the continental landmass of Eurasia with the continent of Europe . Asia covers an ___MASK48___ of , about 30 % of Earth ' s total land ___MASK48___ and 8 . 7 % of the Earth ' s total surface ___MASK48___ . The continent , which has long been home to the majority of the human population , was the site of many of the first civilizations . Asia is notable for not only its overall large size and population , but also dense and large settlements as well as vast barely populated regions within the continent of 4 . 4 billion people . Velafrons ( meaning `` sailed forehead '' ) is a genus of lambeosaurine hadrosaurid ___MASK71___ from the Late Cretaceous of Mexico . It is known from a mostly complete skull and partial skeleton of a juvenile individual , with a bony crest on the forehead . Its fossils were found in the late Campanian - age Upper Cretaceous Cerro del Pueblo Formation ( about 72 million years old ) , near Rincon Colorado , Coahuila , Mexico . The type specimen is CPC - 59 , and the type species is V . coahuilensis . Velafrons was most similar to young specimens of Corythosaurus and Hypacrosaurus , and was found to be a corythosaurin in the phylogenetic analysis performed by Gates and colleagues in their description of the genus . The skull was large in comparison to skulls from other genera at a similar growth stage , so the crest may have been small in adults or followed a different growth pattern , or it may be that adult Velafrons were also larger than adults of other lambeosaurine genera . Unusually large size is also seen in the Mexican hadrosaurids Kritosaurus sp . and Magnapaulia laticaudus . As a hadrosaurid , Velafrons would have been an herbivore . Ornithopods or members of the clade Ornithopoda ( or ) are a group of ornithischian dinosaurs that started out as small , bipedal running grazers , and grew in size and numbers until they became one of the most successful groups of herbivores in the Cretaceous world , and dominated the North American landscape . Their major evolutionary advantage was the progressive development of a chewing apparatus that became the most sophisticated ever developed by a non - avian ___MASK71___ , rivaling that of modern mammals such as the domestic cow . They reached their apex in the duck - bills ( hadrosaurs ), before they were wiped out by the Cretaceous  Paleogene extinction event along with all other non - avian dinosaurs . Members are known from all seven continents , though they are generally rare in the Southern Hemisphere . A herbivore is an ___MASK62___ anatomically and physiologically adapted to eating ___MASK92___ material , for example foliage , for the main component of its diet . As a result of their ___MASK92___ diet , herbivorous animals typically have mouthparts adapted to rasping or grinding . Horses and other herbivores have wide flat teeth that are adapted to grinding grass , tree bark , and other tough ___MASK92___ material . The Cerro del Pueblo Formation is a geological formation in Coahuila , Mexico whose strata date back to the Late Cretaceous . ___MASK71___ remains are among the fossils that have been recovered from the formation . The formation has been dated to between 72 . 5 Ma and 71 . 4 million years old . The Triassic is a geologic period and system which spans 50 . 9 million years from the end of the Permian Period million years ago ( ___MASK54___ ), to the beginning of the Jurassic Period ___MASK54___ . The Triassic is the first period of the Mesozoic Era . Both the start and end of the period are marked by major extinction events . The Triassic was named in 1834 by Friedrich von Alberti , after the three distinct rock layers (" tri " meaning " three ") that are found throughout Germany and northwestern Europe  red beds , capped by marine limestone , followed by a series of terrestrial mud - and sandstones  called the " Trias ". ___MASK3___ is an extinct clade of mainly herbivorous dinosaurs characterized by a pelvic structure similar to that of birds . The name " ___MASK3___ ", or " ___MASK52___ - hipped ", reflects this similarity and is derived from the Greek ' meaning " of a ___MASK52___ " and ' meaning " hip joint ". Birds are members of the saurischian , or " ___MASK86___ - hipped ", dinosaurs . Binomial nomenclature ( also called binominal nomenclature or binary nomenclature ) is a formal system of naming species of living things by giving each a name composed of two parts , both of which use Latin grammatical forms , although they can be based on words from other languages . Such a name is called a binomial name ( which may be shortened to just " binomial "), a binomen or a scientific name ; more informally it is also called a Latin name . The first part of the name identifies the genus to which the species belongs ; the second part identifies the species within the genus . For example , humans belong to the genus " ___MASK67___ " and within this genus to the species " ___MASK67___ sapiens ". The " formal " introduction of this system of naming species is credited to Carl Linnaeus , effectively beginning with his work " Species Plantarum " in 1753 . But Gaspard Bauhin , in as early as 1623 , had introduced in his book " Pinax theatri botanici " ( English , " Illustrated exposition of plants ") many names of genera that were later adopted by Linnaeus . Parasaurolophus ( or ; meaning " near crested ___MASK86___ " in reference to " Saurolophus ") is a genus of ornithopod dinosaur that lived in what is now North America during the Late Cretaceous Period , about 76 . 5  74 . 5 million years ago . It was a herbivore that walked both as a biped and a quadruped . Three species are recognized : " P . walkeri " ( the type species ), " P . tubicen ", and the short - crested " P . cyrtocristatus ". Remains are known from Alberta ( Canada ), and New Mexico and Utah ( United States ). The genus was first described in 1922 by William Parks from a skull and partial skeleton found in Alberta . Guadalajara is the capital and largest city of the Mexican state of Jalisco , and the seat of the municipality of Guadalajara . The city is in the central region of Jalisco in the Western - Pacific ___MASK48___ of Mexico . With a population of 1 , 495 , 189 it is Mexico ' s fourth most populous municipality . The Guadalajara Metropolitan ___MASK48___ includes seven adjacent municipalities with a reported population of 4 , 328 , 584 in 2009 , making it the second most populous metropolitan ___MASK48___ in Mexico , behind Mexico City . The municipality is the second most densely populated in Mexico , the first being Ciudad Nezahualcóyotl in the State of Mexico . It is a strong business and economic center in the Bajio region . Mexico (, modern Nahuatl ), officially the United Mexican States , is a federal republic in the southern half of North America . It is bordered to the north by the United States ; to the south and west by the Pacific Ocean ; to the southeast by Guatemala , Belize , and the Caribbean Sea ; and to the east by the Gulf of Mexico . Covering almost two million square kilometers ( over 760 , 000 sq mi ), Mexico is the sixth largest country in the Americas by total ___MASK48___ and the 13th largest independent nation in the world . With an estimated population of over 120 million , it is the eleventh most populous country and the most populous Spanish - speaking country in the world while being the second most populous country in Latin America . Mexico is a federation comprising 31 states and a federal district that is also its capital and most populous city . Other metropolises include Guadalajara , Monterrey , Puebla , Toluca , Tijuana and León . The Cretaceous is a geologic period and system that spans 79 million years from the end of the Jurassic Period million years ago ( ___MASK54___ ) to the beginning of the Paleogene Period ___MASK54___ . It is the last period of the Mesozoic Era . The Cretaceous Period is usually abbreviated K , for its German translation " Kreide " ( chalk ). In biology , an organism is any contiguous living system , such as an ___MASK62___ , ___MASK92___ , fungus , archaeon , or bacterium . All known types of organisms are capable of some degree of response to stimuli , reproduction , growth and development and homeostasis . An organism consists of one or more cells ; when it has one cell it is known as a unicellular organism ; and when it has more than one it is known as a multicellular organism . Most unicellular organisms are of microscopic scale and are thus loosely described as microorganisms . Humans are multicellular organisms composed of many trillions of cells grouped into specialized tissues and organs . ___MASK72___ is a group of crested hadrosaurid dinosaurs . Classification . Lambeosaurines have been traditionally split into the tribes or clades Parasaurolophini (" Parasaurolophus ", " Charonosaurus ", others (?).) and Lambeosaurini (" Corythosaurus ", " Hypacrosaurus ", " Lambeosaurus ", others .). Corythosaurini ( sinonym of Lambeosaurini , see below ) and Parasaurolophini as terms entered the formal literature in Evans and Reisz ' s 2007 redescription of " Lambeosaurus magnicristatus ". Corythosaurini was defined as all taxa more closely related to " Corythosaurus casuarius " than to " Parasaurolophus walkeri ", and Parasaurolophini as all those taxa closer to " P . walkeri " than to " C . casuarius ". In this study , " Charonosaurus " and " Parasaurolophus " are parasaurolophins , and " Corythosaurus ", " Hypacrosaurus ", " Lambeosaurus ", " Nipponosaurus ", and " Olorotitan " are corythosaurins . However , later researchers pointed out that due to the rules of priority set forth by the ICZN , Any tribe containing " Lambeosaurus " is properly named Lambeosaurini , and that therefore the name " Corythosaurini " is a junior synonym , and the definition had " Corythosaurus casuarius " changed to " Lambeosaurus lambei ", and the same for Parasaurolophini . In more recent years Tsintaosaurini (" Tsintaosaurus " + " Pararhabdodon ") and Aralosaurini (" Aralosaurus " + " Canardia ") have also emerged . ___MASK80___ is a subfamily of hadrosaurid dinosaurs . It has since the mid - 20th century generally been called the ___MASK13___ , a group of largely non - crested hadrosaurs related to the crested sub - family ___MASK72___ . However , the name ___MASK13___ is based on the genus " Hadrosaurus " which was found in more recent studies to be more primitive than either lambeosaurines or other traditional " hadrosaurines ", like " Edmontosaurus " and " Saurolophus ". As a result of this , the name ___MASK13___ was dropped or restricted to " Hadrosaurus " alone , and the subfamily comprising the traditional " hadrosaurines " was renamed the ___MASK80___ . Recent phylogenetic work by Hai Xing indicates that " Hadrosaurus " is placed within the monophyletic group containing all non - lambeosaurine hadrosaurids . Therefore , the traditional ___MASK13___ should be treated as before : Hadrosauridae is divided into two clades : ___MASK13___ and ___MASK72___ . The Paleogene ( or ; also spelled Palaeogene or Palæogene ; informally Lower Tertiary ) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period million years ago ( ___MASK54___ ) to the beginning of the Neogene Period ___MASK54___ . It is the beginning of the Cenozoic Era of the present Phanerozoic Eon . The Paleogene is most notable for being the time during which mammals diversified from relatively small , simple forms into a large group of diverse animals in the wake of the Cretaceous  Paleogene extinction event that ended the preceding Cretaceous Period . Toluca , officially called Toluca de Lerdo , is the state capital of State of Mexico as well as the seat of the Municipality of Toluca . It is the center of a rapidly growing urban ___MASK48___ , now the fifth largest in Mexico . It is located west - southwest of Mexico City , about 40 minutes by car to the western edge of the city . According to the 2010 census , the city of Toluca has a population of 819 , 561 . The city is the fifth largest in Mexico in population . The municipality of Toluca , along with thirteen other municipalities , make up the metropolitan population of 1 , 775 , 337 in Greater Toluca , making it the fifth most populous metropolitan ___MASK48___ in Mexico . ___MASK36___ is a genus of hadrosaurid ( duck - billed ) dinosaur . It contains two known species : " ___MASK36___ regalis " and " ___MASK36___ annectens ". Fossils of " E . regalis " have been found in rocks of western North America that date from the late Campanian stage of the Cretaceous Period 73 million years ago , while those of " E . annectens " were found in the same geographic region but in rocks dated to the end of the Maastrichtian stage of the Cretaceous , 66 million years ago . " ___MASK36___ " was one of the last non - avian dinosaurs , and lived alongside dinosaurs like " Triceratops " and " Tyrannosaurus " shortly before the Cretaceous  Paleogene extinction event . The Triassic  Jurassic extinction event marks the boundary between the Triassic and Jurassic periods , , and is one of the major extinction events of the Phanerozoic eon , profoundly affecting life on land and in the oceans . In the seas , a whole class ( conodonts ) and 34 % of marine genera disappeared . On land , all pseudosuchians ( non - ornithodiran archosaurs ) other than crocodylomorphs ( ___MASK7___ and Crocodyliformes ), some remaining therapsids , and many of the large amphibians became extinct . Guatemala (, or ), officially the Republic of Guatemala , is a country in Central America bordered by Mexico to the north and west , the Pacific Ocean to the southwest , Belize to the northeast , the Caribbean to the east , Honduras to the east and El Salvador to the southeast . With an estimated population of around 15 . 8 million , it is the most populated state in Central America . A representative democracy , Guatemala ' s capital and largest city is Nueva Guatemala de ___MASK26___ Asunción , also known as Guatemala City . Coahuila , formally Coahuila de Zaragoza , officially the Free and Sovereign State of Coahuila de Zaragoza , is one of the 31 states which , along with Mexico City , compose the 32 Federal Entities of Mexico . The state is located in Northeastern Mexico on the US border . Bean is a common name for large seeds of several genera of the flowering ___MASK92___ family Fabaceae ( also known as Leguminosae ) which are used for human or animal food . The Late Cretaceous ( 100 . 5  66 Ma ) is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale . Rock strata from this epoch form the Upper Cretaceous series . The Cretaceous is named after the white limestone known as chalk which occurs widely in northern France and is seen in the white cliffs of south - eastern England , and which dates from this time . Dinosaurs are a diverse group of animals of the clade Dinosauria that first appeared during the Triassic . Although the exact origin and timing of the evolution of dinosaurs is the subject of active research , the current scientific consensus places their origin between 231 and 243 million years ago . They became the dominant terrestrial vertebrates after the Triassic  Jurassic extinction event 201 million years ago . Their dominance continued through the Jurassic and Cretaceous periods and ended when the Cretaceous  Paleogene extinction event led to the extinction of most ___MASK71___ groups 66 million years ago . Monterrey , is the capital and largest city of the northeastern state of Nuevo León , in Mexico . The city is anchor to the third - largest metropolitan ___MASK48___ in Mexico and is ranked as the ninth - largest city in the nation . Monterrey serves as a commercial center in the north of the country and is the base of many significant international corporations .