A proboscis () is an elongated appendage from the head of an animal, either a
vertebrate
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...
or an
invertebrate
Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...
. In invertebrates, the term usually refers to tubular
mouthparts used for feeding and sucking. In vertebrates, a proboscis is an elongated nose or snout.
Etymology
First attested in English in 1609 from Latin , the
latinisation of the
Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...
(), which comes from () 'forth, forward, before' + (), 'to feed, to nourish'. The plural as derived from the Greek is , but in English the plural form ''proboscises'' occurs frequently.
Invertebrates
The most common usage is to refer to the tubular feeding and sucking organ of certain invertebrates such as insects (e.g.,
moths, butterflies, and mosquitoes), worms (including
Acanthocephala
Acanthocephala (Greek , ', thorn + , ', head) is a phylum of parasitic worms known as acanthocephalans, thorny-headed worms, or spiny-headed worms, characterized by the presence of an eversible proboscis, armed with spines, which it uses to p ...
,
proboscis worms) and
gastropod
The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda ().
This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...
molluscs.
Acanthocephala
The
Acanthocephala
Acanthocephala (Greek , ', thorn + , ', head) is a phylum of parasitic worms known as acanthocephalans, thorny-headed worms, or spiny-headed worms, characterized by the presence of an eversible proboscis, armed with spines, which it uses to p ...
or thorny-headed worms, or spiny-headed worms are characterized by the presence of an eversible proboscis, armed with spines, which it uses to pierce and hold the
gut wall of its host.
Lepidoptera mouth parts
The mouth parts of Lepidoptera mainly consist of the sucking kind; this part is known as the proboscis or 'haustellum'. The proboscis consists of two tubes held together by hooks and separable for cleaning. The proboscis contains muscles for operating. Each tube is inwardly concave, thus forming a central tube up which moisture is sucked. Suction takes place due to the contraction and expansion of a sac in the head.
[Evans, W. H. (1927]
''Identification of Indian Butterflies''
The Diocesan press. Introduction, pp. 1–35. A specific example of the proboscis being used for feeding is in the species ''
Deilephila elpenor
Deilephila elpenor, the elephant hawk moth or large elephant hawk moth, is a moth in the family Sphingidae. Its common name is derived from the caterpillar's resemblance to an elephant's trunk. It is most common in central Europe and is distribut ...
''. In this species, the moth hovers in front of the flower and extends its long proboscis to attain its food.
A few Lepidoptera species lack mouth parts and therefore do not feed in the
imago
In biology, the imago (Latin for "image") is the last stage an insect attains during its metamorphosis, its process of growth and development; it is also called the imaginal stage, the stage in which the insect attains maturity. It follows the f ...
. Others, such as the family
Micropterigidae
Micropterigoidea is the superfamily of "mandibulate archaic moths", all placed in the single family Micropterigidae, containing currently about twenty living genera. They are considered the most primitive extant lineage of lepidoptera (Kristense ...
, have mouth parts of the chewing kind.
[Charles A. Triplehorn and Norman F. Johnson (2005). ''Borror and Delong's Introduction to the Study of Insects'' (7th edition). Thomson Brooks/Cole, Belmont, CA. ]
The study of insect mouthparts was helpful for the understanding of the functional mechanism of the proboscis of
butterflies
Butterflies are insects in the macrolepidopteran clade Rhopalocera from the Order (biology), order Lepidoptera, which also includes moths. Adult butterflies have large, often brightly coloured wings, and conspicuous, fluttering flight. The ...
(Lepidoptera) to elucidate the evolution of new form-function.
The study of the proboscis of butterflies revealed surprising examples of adaptations to different kinds of fluid food, including
nectar
Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists ...
,
plant sap
Sap is a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant.
Sap is distinct from latex, resin, or cell sap; it is a sepa ...
, tree sap, dung
and of adaptations to the use of
pollen
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...
as complementary food in ''
Heliconius
''Heliconius'' comprises a colorful and widespread genus of brush-footed butterflies commonly known as the longwings or heliconians. This genus is distributed throughout the tropical and subtropical regions of the New World, from South America a ...
'' butterflies.
An extremely long proboscis appears within different groups of flower-visiting insects, but is relatively rare.
Gastropods
Vertebrates
The elephant's trunk and the
tapir
Tapirs ( ) are large, herbivorous mammals belonging to the family Tapiridae. They are similar in shape to a pig, with a short, prehensile nose trunk. Tapirs inhabit jungle and forest regions of South and Central America, with one species inh ...
's elongated nose are called "proboscis", as is the snout of the male
elephant seal
Elephant seals are very large, oceangoing earless seals in the genus ''Mirounga''. Both species, the northern elephant seal (''M. angustirostris'') and the southern elephant seal (''M. leonina''), were hunted to the brink of extinction for oi ...
.
The
proboscis monkey is named for its enormous nose.
An abnormal facial appendage that sometimes accompanies ocular and nasal abnormalities in humans is also called a proboscis.
Notable mammals with some form of proboscis are:
*
Aardvark
The aardvark ( ; ''Orycteropus afer'') is a medium-sized, burrowing, nocturnal mammal native to Africa. It is the only living species of the order Tubulidentata, although other prehistoric species and genera of Tubulidentata are known. Unlik ...
*
Anteater
* Members of the elephant family (see
elephant trunk)
*
Elephant shrew
Elephant shrews, also called jumping shrews or sengis, are small insectivorous mammals native to Africa, belonging to the family Macroscelididae, in the order Macroscelidea. Their traditional common English name "elephant shrew" comes from a perc ...
s
*
Hispaniolan solenodon
The Hispaniolan solenodon (''Solenodon paradoxus'') is a small, furry, shrew-like mammal endemic to the Caribbean island of Hispaniola (in the Dominican Republic and Haiti). Like other solenodons, it is a venomous, insect-eating animal that liv ...
*
Echidna
Echidnas (), sometimes known as spiny anteaters, are quill-covered monotremes (egg-laying mammals) belonging to the family Tachyglossidae . The four extant species of echidnas and the platypus are the only living mammals that lay eggs and the ...
*
Elephant seal
Elephant seals are very large, oceangoing earless seals in the genus ''Mirounga''. Both species, the northern elephant seal (''M. angustirostris'') and the southern elephant seal (''M. leonina''), were hunted to the brink of extinction for oi ...
* ''
Leptictidium'' (extinct)
* ''
Moeritherium
''Moeritherium'' ("the beast from Lake Moeris") is an extinct genus of primitive proboscideans. These prehistoric mammals are related to the elephant and, more distantly, sea cows and hyraxes. They lived during the Eocene epoch.
Description
''M ...
'' (extinct)
* ''
Macrauchenia
''Macrauchenia'' ("long llama", based on the now-invalid llama genus, ''Auchenia'', from Greek "big neck") was a large, long-necked and long-limbed, three-toed native South American mammal in the order Litopterna. The genus gives its name to its ...
'' (extinct)
*
Numbat
The numbat (''Myrmecobius fasciatus''), also known as the noombat or walpurti, is an insectivorous marsupial. It is diurnal and its diet consists almost exclusively of termites.
The species was once widespread across southern Australia, but ...
*
Proboscis monkey
*
Saiga
The saiga antelope (, ''Saiga tatarica''), or saiga, is a critically endangered antelope which during antiquity inhabited a vast area of the Eurasian steppe spanning the foothills of the Carpathian Mountains in the northwest and Caucasus in t ...
* Members of the
Tapir
Tapirs ( ) are large, herbivorous mammals belonging to the family Tapiridae. They are similar in shape to a pig, with a short, prehensile nose trunk. Tapirs inhabit jungle and forest regions of South and Central America, with one species inh ...
family
References
{{Authority control
Animal anatomy