''Torotix'' is a
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of
aquatic bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...
s. They lived along the shores of the
Western Interior Seaway
The Western Interior Seaway (also called the Cretaceous Seaway, the Niobraran Sea, the North American Inland Sea, and the Western Interior Sea) was a large inland sea that split the continent of North America into two landmasses. The ancient sea, ...
, but it is not clear whether they were seabirds or freshwater birds, as the genus is only known from a
humerus
The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...
. Consequently, the genus contains only one known species, ''Torotix clemensi''. ''T. clemensi'' is represented by a single fossil specimen, a partial humerus (upper arm bone) recovered from the
Lance formation
The Lance (Creek) Formation is a division of Late Cretaceous (dating to about 69 - 66 Ma) rocks in the western United States. Named after Lance Creek, Wyoming, the microvertebrate fossils and dinosaurs represent important components of the late ...
of
Wyoming
Wyoming () is a U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the south ...
. Its deposits are dated to the very end of the
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...
period, 66 million years ago.
Classification
''Torotix'' was first described by Brodkorb in 1963, who initially suggested that it was related to modern
flamingo
Flamingos or flamingoes are a type of Wader, wading bird in the Family (biology), family Phoenicopteridae, which is the only extant family in the order Phoenicopteriformes. There are four flamingo species distributed throughout the Americas ...
s, in the order
Phoenicopteriformes
Phoenicopteriformes is a group of water birds which comprises flamingos and their extinct relatives. Flamingos (Phoenicopteriformes) and the closely related grebes ( Podicipedidae) are contained in the parent clade Mirandornithes.
Fossil rec ...
.
[Brodkorb (1963). "Birds from the Upper Cretaceous of Wyoming." pp. 50–70 in Sibley (ed.), ''Proceedings of the XIII International Ornithological Congress''.] Later researchers thought it was more likely to have been related to the
Charadriiformes
Charadriiformes (, from ''Charadrius'', the type genus of family Charadriidae) is a diverse order of small to medium-large birds. It includes about 390 species and has members in all parts of the world. Most charadriiform birds live near water an ...
(waders/shorebirds).
[Olson, S. (1985). "The fossil record of birds." pp. 79–239 in Farner, King and Parkes (eds.), ''Avian Biology vol VIII''. New York: Academic Press.] More recent comparative studies have found it to be most similar to
Pelecaniformes
The Pelecaniformes are an order of medium-sized and large waterbirds found worldwide. As traditionally—but erroneously—defined, they encompass all birds that have feet with all four toes webbed. Hence, they were formerly also known by such ...
.
[Hope, S. (2002). "The Mesozoic radiation of Neornithes." pp. 339–388 in Chiappe, L. and Witmer, L.M. (eds), ''Mesozoic Birds: Above the Heads of Dinosaurs''. Berkeley: University of California Press.]
A
cladistic
Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived char ...
study of the wing bone found ''Torotix'' not to resemble that of the
waved albatross
The waved albatross (''Phoebastria irrorata''), also known as Galapagos albatross,Remsen Jr., J.V. (2008) is the only member of the family Diomedeidae located in the tropics. When they forage, they follow a straight path to a single site off the ...
(a procellariiform),
northern gannet
The northern gannet (''Morus bassanus'') is a seabird, the largest species of the gannet family, Sulidae. It is native to the coasts of the Atlantic Ocean, breeding in Western Europe and Northeastern North America. It is the largest seabird in t ...
(of the
order Suliformes),
painted buttonquail
The painted buttonquail (''Turnix varius'') is a species of buttonquail, the family Turnicidae, which resemble, but are unrelated to, the quails of Phasianidae. This species is resident in Australia where numbers are believed to be in decline. ...
(an ancient charadriiform),
black-necked stilt (a more advanced charadriiform) or a ''
Phoenicopterus
''Phoenicopterus'' is a genus of birds in the flamingo family Phoenicopteridae.
Taxonomy
The genus ''Phoenicopterus'' was introduced in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his ''Systema Naturae'' to accommodate ...
'' flamingo noticeably more than any other. However, this comparison provided information only about ecological rather than
phylogenetic
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
similarities.
The
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Torotigidae was initially established to unite this genus with ''
Parascaniornis'' and ''
Gallornis
''Gallornis'' is a genus of prehistoric birds from the Cretaceous. The single known species ''Gallornis straeleni'' lived near today's Auxerre in Yonne ''département'' (France); it has been dated very tentatively to the Berriasian-Hauterivian st ...
''. However, the former is now considered a
junior synonym
The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently.
* In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linna ...
of ''
Baptornis
''Baptornis'' ("diving bird") is a genus of flightless, aquatic birds from the Late Cretaceous, some 87-80 million years ago (roughly mid-Coniacian to mid-Campanian faunal stages). The fossils of ''Baptornis advenus'', the type species, were dis ...
'' (a
hesperornithine
Hesperornithes is an extinct and highly specialized group of aquatic avialans closely related to the ancestors of modern birds. They inhabited both marine and freshwater habitats in the Northern Hemisphere, and include genera such as ''Hesperorni ...
), while the latter may be a very early
fowl
Fowl are birds belonging to one of two biological orders, namely the gamefowl or landfowl (Galliformes) and the waterfowl (Anseriformes). Anatomical and molecular similarities suggest these two groups are close evolutionary relatives; together ...
of the group
Galloanserae.
Footnotes
Pelecaniformes
Bird genera
Late Cretaceous birds of North America
Fossil taxa described in 1963
{{Pelecaniformes-stub