The skimmers, forming the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

''Rynchops'', are

tern Terns are seabirds in the family Laridae that have a worldwide distribution and are normally found near the sea, rivers, or wetlands. Terns are treated as a subgroup of the family Laridae which includes gulls and skimmers and consists of e ...

-like birds in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Laridae Laridae is a family of seabirds in the order Charadriiformes that includes the gulls, terns, skimmers and kittiwakes. It includes around 100 species arranged into 22 genera. They are an adaptable group of mostly aerial birds found worldwide. ...

. The genus comprises three species found in

South Asia South Asia is the southern subregion of Asia, which is defined in both geographical Geography (from Greek: , ''geographia''. Combination of Greek words ‘Geo’ (The Earth) and ‘Graphien’ (to describe), literally "earth descr ...

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

, and the

Americas The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World. Along with th ...

. They were formerly known as the scissorbills. The three species are the only birds with distinctive uneven bills, where the lower mandible is longer than the upper. This remarkable adaptation allows them to fish in a unique way, flying low and fast over streams. Their lower mandible skims or slices over the water's surface, ready to snap shut any small fish unable to dart clear. The skimmers are sometimes included within the gull family Laridae but separated in other treatments which consider them as a sister group of the

s. The black skimmer has an additional adaptation and is the only species of bird known to have slit-shaped

pupils The pupil is a black hole located in the center of the iris of the eye that allows light to strike the retina.Cassin, B. and Solomon, S. (1990) ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company. It appears black ...

. Their bills fall within their field of binocular vision, which enables them to carefully position their bill and capture prey. They are agile in flight and gather in large flocks along rivers and coastal sand banks. They are tropical and subtropical species which lay 3–6 eggs on sandy beaches. The female incubates the eggs. Because of the species' restricted nesting habitat the three species are vulnerable to disturbance at their nesting sites. One species, the

Indian skimmer The Indian skimmer or Indian scissors-bill (''Rynchops albicollis'') is one of the three species that belong to the skimmer genus ''Rynchops'' in the family Laridae. They are somewhat tern-like but like other skimmers, have a short upper mandibl ...

, is considered vulnerable by the IUCN due to this as well as destruction and degradation of the lakes and rivers it uses for feeding. As in later editions of the works of

Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

, the correct spelling (from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

words and , together meaning "beak-face") should be ''rhynchops'' and this is often adopted. However, the misspelling ''rynchops'' was the one first published by Linnaeus and continues to be more commonly used. Similarly, the gender of the Greek and Roman words is feminine and the genus was originally treated as such (''R. nigra'') but ''Rynchops'' is now usually treated as a masculine noun (''R. niger'').

Taxonomy

The

''Rynchops'' was introduced in 1758 by the Swedish naturalist

Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his Nobility#Ennoblement, ennoblement in 1761 as Carl von Linné#Blunt, Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalise ...

in the tenth edition of his '' Systema Naturae''. The genus name ''Rynchops'' is from 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 p ...

ῥυγχος/''rhunkhos'' meaning "bill" and κοπτω/''koptō'' meaning "to cut off". The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

is the black skimmer (''Rynchops niger'').

Species

The genus contains three species.

Notes

References

External links

Skimmer videos
on the Internet Bird Collection {{Authority control Taxa named by Carl Linnaeus