14-521: The family Alligatoridae of crocodylians includes alligators , caimans and their extinct relatives. The superfamily Alligatoroidea includes all crocodilians (fossil and extant) that are more closely related to the American alligator than to either the Nile crocodile or the gharial . This is a stem-based definition for alligators , and is more inclusive than the crown group Alligatoridae. As
28-441: A crown group, Alligatoridae only includes the last common ancestor of all extant (living) alligators, caimans, and their descendants (living or extinct ), whereas Alligatoroidea, as a stem-based group, also includes more basal extinct alligator ancestors that are more closely related to living alligators than to crocodiles or gavialids . When considering only living taxa ( neontology ), Alligatoroidea and Alligatoridae contain
42-554: A lack of widespread consensus within the scientific community for extended periods. The continual publication of new data and diverse opinions plays a crucial role in facilitating adjustments and ultimately reaching a consensus over time. The naming of families is codified by various international bodies using the following suffixes: The taxonomic term familia was first used by French botanist Pierre Magnol in his Prodromus historiae generalis plantarum, in quo familiae plantarum per tabulas disponuntur (1689) where he called
56-520: Is an extinct genus of alligatorid from the Eocene of North America . It was named posthumously in 1946 by Charles W. Gilmore ; the type species is P. utahensis , from the Uintan (middle Eocene) of Utah . It is based on USNM 15996, a nearly complete skull and partial left hind leg. A second species, P. kayi , was named in 1941 by C.C. Mook as a species of Hassiacosuchus , for remains from
70-499: Is commonly referred to as the "walnut family". The delineation of what constitutes a family— or whether a described family should be acknowledged— is established and decided upon by active taxonomists . There are not strict regulations for outlining or acknowledging a family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to
84-485: Is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy . It is classified between order and genus . A family may be divided into subfamilies , which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae , but that family
98-476: The Genera Plantarum of George Bentham and Joseph Dalton Hooker this word ordo was used for what now is given the rank of family. Families serve as valuable units for evolutionary, paleontological, and genetic studies due to their relatively greater stability compared to lower taxonomic levels like genera and species. Procaimanoidea Procaimanoidea ("Before Caiman -forms")
112-461: The Bridgerian (early Eocene) of Wyoming . It was reassigned to Procaimanoidea in 1967 by Wassersug and Hecht. Procaimanoidea was a small alligatorid, and slightly heterodont , the last four teeth on each side of the jaws having blunt tips. Recent studies have consistently resolved Procaimanoidea as a member of Alligatorinae , although its relative placement is disputed, as shown by
126-540: The family as a rank intermediate between order and genus was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes, disposés dans un ordre naturel (1796). He used families (some of them were not named) in some but not in all his orders of "insects" (which then included all arthropods ). In nineteenth-century works such as the Prodromus of Augustin Pyramus de Candolle and
140-961: The internal relationships within Alligatoridae including fossil species, based on morphological analysis (although the exact alligatoroid phylogeny is still disputed). Leidyosuchus † Diplocynodon † Ceratosuchus † Allognathosuchus † Navajosuchus † Arambourgia † Procaimanoidea † Wannaganosuchus † Alligator prenasalis † Alligator mcgrewi † Alligator olseni † Alligator sinensis Chinese alligator Culebrasuchus † Alligator mississippiensis American alligator Alligator mefferdi † Alligator thomsoni † Stangerochampsa † Albertochampsa † Brachychampsa † Protocaiman † Gnatusuchus † Globidentosuchus † Eocaiman † Family (biology) Family ( Latin : familia , pl. : familiae )
154-772: The same species. The simplified cladogram below shows Alligatoridae's relationships to other extant (living) crocodilians. Leidyosuchus † Diplocynodon † extinct basal Alligatoroid Globidontans † Caiman [REDACTED] Melanosuchus [REDACTED] Paleosuchus [REDACTED] Alligator [REDACTED] extinct basal Crocodilians † (possibly including Mekosuchinae † ) extinct basal crocodiles † Crocodylidae ( crown group ) [REDACTED] extinct basal Gavialoids † Gavialis [REDACTED] Tomistoma [REDACTED] Alligatoridae contains eight living species: two alligators within Alligatorinae , and
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#1732772610670168-575: The seventy-six groups of plants he recognised in his tables families ( familiae ). The concept of rank at that time was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera , which is far from how the term is used today. In his work Philosophia Botanica published in 1751, Carl Linnaeus employed the term familia to categorize significant plant groups such as trees , herbs , ferns , palms , and so on. Notably, he restricted
182-543: The six caimans of Caimaninae . Phylogenetic studies using molecular DNA consistently resolve their relationships as follows: Paleosuchus palpebrosus Cuvier's dwarf caiman Paleosuchus trigonatus Schneider's dwarf caiman Caiman crocodilus Spectacled caiman Caiman yacare Yacare caiman Caiman latirostris Broad-snouted caiman Melanosuchus niger Black caiman Alligator sinensis Chinese alligator Alligator mississippiensis American alligator The below detailed cladogram shows one proposal for
196-549: The use of this term solely within the book's morphological section, where he delved into discussions regarding the vegetative and generative aspects of plants. Subsequently, in French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille was used as a French equivalent of the Latin ordo (or ordo naturalis ). In zoology ,
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