The

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Threskiornithidae includes 36 species of large wading birds. The family has been traditionally classified into two subfamilies, the

ibis The ibis () (collective plural ibises; classical plurals ibides and ibes) are a group of long-legged wading birds in the family Threskiornithidae that inhabit wetlands, forests and plains. "Ibis" derives from the Latin and Ancient Greek word f ...

es and the

spoonbill Spoonbills are a genus, ''Platalea'', of large, long-legged wading birds. The spoonbills have a global distribution, being found on every continent except Antarctica. The genus name ''Platalea'' derives from Ancient Greek and means "broad", refe ...

s; however, recent genetic studies have cast doubt on this arrangement, and have found the spoonbills to be nested within the Old World ibises, and the New World ibises as an early offshoot.

Taxonomy

The family Threskiornithidae was formerly known as Plataleidae. The spoonbills and ibises were once thought to be related to other groups of long-legged wading birds in the order

Ciconiiformes Storks are large, long-legged, long-necked wading birds with long, stout bills. They belong to the family Ciconiidae, and make up the order Ciconiiformes . Ciconiiformes previously included a number of other families, such as herons and ibise ...

. A recent study found that they are members of the order

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 ...

. In response to these findings, the

International Ornithological Congress International is an adjective (also used as a noun) meaning "between nations". International may also refer to: Music Albums * ''International'' (Kevin Michael album), 2011 * ''International'' (New Order album), 2002 * ''International'' (The T ...

(IOC) recently reclassified Threskiornithidae and their sister taxa

Ardeidae Herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 75 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genus '' Botaurus'' are referred to as ...

under the order

instead of the previous order of Ciconiiformes. Whether the two subfamilies are reciprocally

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

is an open question. The South American Checklist Committee's entry for the Threskiornithidae includes the following comment "Two subfamilies are traditionally (e.g., Matheu & del Hoyo 1992) recognized: Threskiornithinae for ibises and Plataleinae for spoonbills; because the main distinction has to do with bill shape, additional information, especially genetic, is required to recognize a major, deep split in the family." A study of

mitochondrial DNA Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondrion, mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the D ...

of the spoonbills plus the

sacred Sacred describes something that is dedicated or set apart for the service or worship of a deity; is considered worthy of spiritual respect or devotion; or inspires awe or reverence among believers. The property is often ascribed to objects ( ...

and

scarlet ibis The scarlet ibis, sometimes called red ibis (''Eudocimus ruber''), is a species of ibis in the bird family Threskiornithidae. It inhabits tropical South America and part of the Caribbean. In form, it resembles most of the other twenty-seven ex ...

es found that the spoonbills formed a clade with old world genus '' Threskiornis'', with '' Nipponia nippon'' and '' Eudocimus'' as progressively earlier offshoots and more distant relatives, and hence casts doubt on the arrangement of the family into ibis and spoonbill subfamilies. Subsequent studies have supported these findings, the spoonbills forming a monophyletic clade within the "widespread" clade of ibises, including ''Plegadis'' and ''Threskiornis'', while the "new World Endemic" clade is formed by the genera restricted to the Americas such as ''Eudocimus'' and ''Theristicus''. Ibises are a rather old group, with well-preserved definitive fossils known as far back as the

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

('' Rhynchaeites''), and potential members dating as far back as the

Late Paleocene The Thanetian is, in the International Commission on Stratigraphy, ICS Geologic timescale, the latest age (geology), age or uppermost stage (stratigraphy), stratigraphic stage of the Paleocene epoch (geology), Epoch or series (stratigraphy), Serie ...

('' Dakotornis'').

Description

Members of the family have long, broad wings with 11 primary

feather Feathers are epidermal growths that form a distinctive outer covering, or plumage, on both avian (bird) and some non-avian dinosaurs and other archosaurs. They are the most complex integumentary structures found in vertebrates and an exa ...

s and about 20 secondaries. They are strong fliers and, rather surprisingly, given their size and weight, very capable soarers. The body tends to be elongated, the neck more so, with rather long legs. The bill is also long, decurved in the case of the

es, straight and distinctively flattened in the

s. They are large birds, but mid-sized by the standards of their order, ranging from the dwarf olive ibis (''Bostrychia bocagei''), at and , to the giant ibis (''Thaumatibis gigantea''), at and .

Distribution and ecology

They are distributed almost worldwide, being found near almost any area of standing or slow-flowing fresh or

brackish water Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuary ...

. Ibises are also found in drier areas, including

landfill A landfill is a site for the disposal of waste materials. It is the oldest and most common form of waste disposal, although the systematic burial of waste with daily, intermediate and final covers only began in the 1940s. In the past, waste was ...

s. The

Llanos The Llanos ( Spanish ''Los Llanos'', "The Plains"; ) is a vast tropical grassland plain situated to the east of the Andes in Colombia and Venezuela, in northwestern South America. It is an ecoregion of the tropical and subtropical grasslands, ...

are notable in that these wetland plains support seven species of ibis in the one region. All ibises are diurnal; spending the day feeding on a wide range of

invertebrate Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...

s and small

vertebrate Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebra ...

s: ibises by probing in soft earth or mud, spoonbills by swinging the bill from side to side in shallow water. At night, they roost in trees near water. They are gregarious, feeding, roosting, and flying together, often in formation. Nesting is colonial in ibises, more often in small groups or singly in spoonbills, nearly always in trees overhanging water, but sometimes on islands or small islands in swamps. Generally, the female builds a large structure out of reeds and sticks brought by the male. Typical clutch size is two to five; hatching is asynchronic. Both sexes incubate in shifts, and after hatching feed the young by partial regurgitation. Two or three weeks after hatching, the young no longer need to be brooded continuously and may leave the nest, often forming creches but returning to be fed by the parents.

Species

FAMILY: THRESKIORNITHIDAE * Subfamily: Threskiornithinae – Ibises ** Genus '' Threskiornis'' ***

African sacred ibis The African sacred ibis (''Threskiornis aethiopicus'') is a species of ibis, a wading bird of the family Threskiornithidae. It is native to much of Africa, as well as small parts of Iraq, Iran and Kuwait. It is especially known for its role i ...

, ''Threskiornis aethiopicus'' *** Malagasy sacred ibis, ''Threskiornis bernieri'' *** † Reunion ibis, ''Threskiornis solitarius'' (

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

) *** Black-headed ibis, ''Threskiornis melanocephalus'' *** Australian white ibis, ''Threskiornis molucca'' **** Solomons white ibis, ''Threskiornis molucca pygmaeus'' *** Straw-necked ibis, ''Threskiornis spinicollis'' ** Genus '' Pseudibis'' *** Red-naped ibis, ''Pseudibis papillosa'' *** White-shouldered ibis, ''Pseudibis davisoni'' ** Genus ''Thaumatibis'' *** Giant ibis, ''Thaumatibis gigantea'' ** Genus '' Geronticus'' ***

Northern bald ibis The northern bald ibis, hermit ibis, or Waldrapp (''Geronticus eremita'') is a migratory Old World ibis found in open areas such as grasslands, rocky mountains, and semi-deserts, often close to running water. This glossy black ibis, which, unl ...

, ''Geronticus eremita'' ***

Southern bald ibis The southern bald ibis (''Geronticus calvus'') is a large bird found in open grassland or semi-desert in the mountains of southern Africa. Taxonomically, it is most closely related to its counterpart in the northern regions of Africa, the waldra ...

, ''Geronticus calvus'' ** Genus ''Nipponia'' ***

Crested ibis The crested ibis (''Nipponia nippon''), also known as the Japanese crested ibis, or Asian crested ibis, is a species of ibis, native to eastern Asia. It is the only member of the genus ''Nipponia''. In Japan, where it has special cultural signi ...

, ''Nipponia nippon '' ** Genus '' Bostrychia'' *** Olive ibis, ''Bostrychia olivacea'' ***

São Tomé ibis The São Tomé ibis (''Bostrychia bocagei''), also known as the dwarf olive ibis or the dwarf ibis, is a Critically Endangered, critically endangered bird that is endemism, endemic to São Tomé Island, São Tomé off the western coast of Central ...

, ''Bostrychia bocagei'' *** Spot-breasted ibis, ''Bostrychia rara'' *** Hadada ibis, ''Bostrychia hagedash'' *** Wattled ibis, ''Bostrychia carunculata'' ** Genus '' Theristicus'' *** Plumbeous ibis, ''Theristicus caerulescens'' *** Buff-necked ibis, ''Theristicus caudatus'' ***

Black-faced ibis The black-faced ibis (''Theristicus melanopis'') is a species of bird in the family Threskiornithidae. It is found in grassland and fields in southern and western South America. It has been included as a subspecies of the similar buff-necked i ...

, ''Theristicus melanopis'' ** Genus ''Cercibis'' *** Sharp-tailed ibis, ''Cercibis oxycerca'' ** Genus ''Mesembrinibis'' *** Green ibis, ''Mesembrinibis cayennensis'' ** Genus ''Phimosus'' *** Bare-faced ibis, ''Phimosus infuscatus'' ** Genus '' Eudocimus'' *** American white ibis, ''Eudocimus albus'' ***

Scarlet ibis The scarlet ibis, sometimes called red ibis (''Eudocimus ruber''), is a species of ibis in the bird family Threskiornithidae. It inhabits tropical South America and part of the Caribbean. In form, it resembles most of the other twenty-seven ex ...

, ''Eudocimus ruber'' ** Genus ''

Plegadis ''Plegadis'' is a bird genus in the family (biology), family Threskiornithidae. The genus name derives from Ancient Greek ''plegados'', "sickle", referring to the distinctive shape of the bill. Member species are found on every continent except A ...

'' ***

Glossy ibis The glossy ibis (''Plegadis falcinellus'') is a water bird in the order Pelecaniformes and the ibis and spoonbill family Threskiornithidae. The scientific name derives from Ancient Greek ''plegados'' and Latin, ''falcis'', both meaning "sickle" a ...

, ''Plegadis falcinellus'' *** White-faced ibis, ''Plegadis chihi'' *** Puna ibis, ''Plegadis ridgwayi'' ** Genus ''Lophotibis'' *** Madagascar ibis, ''Lophotibis cristata'' * Subfamily: Plataleinae – Spoonbills ** Genus ''Platalea'' ***

Eurasian spoonbill The Eurasian spoonbill (''Platalea leucorodia''), or common spoonbill, is a wading bird of the ibis and spoonbill family Threskiornithidae, native to Europe, Africa and Asia. The species is partially migratory with the more northerly breeding popu ...

, ''Platalea leucorodia'' ***

Black-faced spoonbill The black-faced spoonbill (''Platalea minor'') is a species of wading bird in the ibis and spoonbill family Threskiornithidae, found in eastern Asia. This species has the most restricted distribution of the six spoonbill species, and it is the ...

, ''Platalea minor'' ***

African spoonbill The African spoonbill (''Platalea alba'') is a long-legged wading birdRoyal spoonbill, ''Platalea regia'' *** Yellow-billed spoonbill, ''Platalea flavipes'' *** Roseate spoonbill, ''Platalea ajaja''

Fossil genera

The following fossil genera are known: * '' Actiornis'' (Late Eocene of England) * ?'' Dakotornis'' (Late Paleocene of

North Dakota North Dakota ( ) is a U.S. state in the Upper Midwest, named after the indigenous Dakota people, Dakota and Sioux peoples. It is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minneso ...

, US) * ?'' Minggangia'' (Late Eocene of China) * '' Rhynchaeites'' (Early to Middle Eocene of England and Germany, potentially Denmark and Wyoming, US) * ?'' Vadaravis'' (Early Eocene of Wyoming, US)

References

External links

Threskiornithidae videos
on the Internet Bird Collection {{Authority control Bird families Extant Ypresian first appearances Taxa named by Charles Wallace Richmond