The genus Zaprionus belongs to the family fruit fly Drosophilidae

Drosophilidae

Drosophilidae is a diverse, cosmopolitan family of flies, which includes fruit flies. Another family of flies called Tephritidae also includes fruit flies. The best known species of Drosophilidae is Drosophila melanogaster, within the genus Drosophila, and this species Is used extensively for...

 and is positioned within the paraphyletic genus Drosophila

Drosophila

Drosophila is a genus of small flies, belonging to the family Drosophilidae, whose members are often called "fruit flies" or more appropriately pomace flies, vinegar flies, or wine flies, a reference to the characteristic of many species to linger around overripe or rotting fruit...

. All species are easily recognized by the white longitudinal stripes across the head and thorax. The genus is subdivided in two subgenera, based on the presence of an even (subgenus Zaprionus) or odd (subgenus Anaprionus) number of white stripes. The species of the genus can be found in found in African and Southern Asia. One species, Zaprionus indianus, has invaded the New World

New World

The New World is one of the names used for the Western Hemisphere, specifically America and sometimes Oceania . The term originated in the late 15th century, when America had been recently discovered by European explorers, expanding the geographical horizon of the people of the European middle...

.

Description

All species in the genus Zaprionus are easily identified by the longitudinal white stripes bordered by black stripes running across the top of the head and thorax. Species of the subgenus Zaprionus have 4 or 6 white stripes while the species of the subgenus Anaprionus have 5 or 7 white stripes. The general body color varies across species from yellowish to dark brown. Several species of the subgenus Zaprionus have one or more stout and sometimes composite spines on the forelegs.

Coloration

The characteristic black and white 'zebra' stripes of this genus have two different origins. In the simplest form, the white stripes are caused by an absence of the pigment

Pigment

A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...

 in the cuticle

Cuticle

A cuticle , or cuticula, is a term used for any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticles" are non-homologous; differing in their origin, structure, function, and chemical composition...

. This mechanism is found in species of the subgenus Anaprionus. The absence of pigmentation also occurs in the species of the subgenus Zaprionus, probably complemented by a separate mechanism. In these species, the white stripes contain many long and bent trichomes (fine outgrowths) that have a groove and contain two cavities, polarizing the light

Light

Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

. The black stripes are caused by pigmentation.

Distribution

Members of this genus can be found in the tropics of most continents. The species of the subgenus Zaprionus are found primarily in Africa

Africa

Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...

, while the species of the subgenus Anaprionus are found in Southeast Asia

Southeast Asia

Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...

. Two species, Zaprionus ghesquierei and Zaprionus indianus have expanded their range in recent times. Zaprionus ghesquierei has invaded

Invasive species

"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....

 Hawaiʻi, while Zaprionus indianus has expanded its range though the Middle East

Middle East

The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...

 towards India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

 and more recently crossed the Atlantic Ocean

Atlantic Ocean

The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

 and colonized both South

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 and North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

.

Ecology

Zaprionus species are found in a wide array of habitats from semi-deserts to the tropical rain forest. Most species breed on fruit

Fruit

In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...

s, flower

Flower

A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...

s or decaying tree trunks.

Taxonomy

The genus Zaprionus was described in 1902 by Daniel William Coquillett

Daniel William Coquillett

Daniel William Coquillett was an American entomologist who specialised in Diptera. He wrote Revision of the dipterous family Therevidae...

. He considered the genus closely related to the genus Drosophila. Molecular studies have confirmed this relationship, and the genus Zaprionus is positioned within the paraphyletic genus Drosophila.

Within the genus, species with an odd number of stripes are assigned to the subgenus Anaprionus, while the species with an even number of stripes are assigned to the subgenus Zaprionus. Species within the subgenus Zaprionus were traditionally subdivided in two species groups, armatus and inermis, based on the presence or absence of special spines on the forelegs. The armatus species group was further subdivided into three species subgroups based on the type of spines. The species of the armatus species subgroup have several normal spines. The single spine on forelegs of the species of the tuberculatus species subgroup consists of a large spine positioned on a tubercle with a smaller spine near the base of the spine. Finally, the species of the vittiger species subgroup had a row of composite spines generally positioned on small tubercles.

Recent molecular studies have show that this subdivision of the Zaprionus subgenus is incorrect. The ornamentation has evolved multiple times and is not a reliable characteristic for classification. The tuberculatus species group is now part of the group lacking ornamentation (inermis), and the closet relatives of species with a large composite spines are closely related to species without such a spine. The vittiger species subgroup is now a species group and a new species group, neglectus, has been erected for one species placed at the root of the Zaprionus subgenus.

Species

Simplified phylogenetic tree of the genus Drosophila and included genera witha focus on the phylogenetic position of the genus Zaprionus.

The genus Zaprionus consists of the following species:

Subgenus Anaprionus: odd number of whites stripes

• Z. aungsani Wynn and Toda, 1988
• Z. bogoriensis Mainx, 1958)
• Z. cercociliaris Gupta and Gupta, 1991
• Z. flavofasciatus (Takada, Beppu and Toda, 1979)
• Z. lineosus (Walker, 1860)
• Z. multistriatus (Duda, 1923)
• Z. obscuricornis (de Meijere, 1916)
• Z. orissaensis (Gupta, 1972)
• Z. pyinoolwinensis Wynn and Toda, 1988
• Z. silvistriatus (Bock and Baimai, 1967)
• Z. spinilineosus Okada and Carson, 1983
• Z. grandis (Kikkawa and Peng, 1938)

Subgenus Zaprionus: even number of white stripes

• Species group armatus: all species have a simple row of spines.
  • Species subgroup armatus: row of undifferentiated spines
    • Species complex armatus: strong undifferentially oriented spines
      • Z. armatus Collart, 1937
      • Z. enoplomerus Chassagnard, 1988
      • Z. seguyi Tsacas and Chassagnard, 1990
      • Z. spinipes Tsacas and Chassagnard, 1990
      • Z. spinoarmatus Tsacas and Chassagnard, 1990
    • Species complex hoplophorus: strong differentially oriented spines
      • Z. hoplophorus Tsacas and Chassagnard, 1990
      • Z. tuberarmatus Tsacas and Chassagnard, 1990
    • Species complex vrydaghi: fine undifferentially oriented spines, wings with black
      • Z. fumipennis Seguy, 1938
      • Z. vrydaghi Collart, 1937
  • Species subgroup montanus: two opposite oriented spines

    • Z. montanus Collart, 1937
    • Z. campestris Chassagnard, 1988

  • Species subgroup spinosus: row of differentiated spines

    • Z. serratus Chassagnard, 1988
    • Z. spineus Tsacas and Chassagnard, 1990
    • Z. spinosus Collart, 1937

• Species group inermis: zero or one modified spines on foreleg

  • Z. arduus Collart, 1937
  • Z. badyi Burla, 1954
  • Z. ghesquierei Collart, 1937
  • Z. momorticus Graber, 1957
  • Z. niabu Burla, 1954

  • Species subgroup inermis

    • Z. cercus Chassagnard and McEvey, 1992
    • Z. inermis Collart, 1937

  • Species subgroup tuberculatus

    • Z. kolodkinae Chassagnard and Tsacas, 1987
    • Z. mascariensis Tsacas and David, 1975

    • Species complex sepsoides
      • Z. sepsoides Duda, 1939
      • Z. tsacasi Yassin, 2008
    • Species complex tuberculatus
      • Z. burlai Yassin, 2008
      • Z. tuberculatus Malloch, 1932
      • Z. verruca Chassagnard and McEvey, 1992
• Species group neglectus

  • Z. neglectus Collart, 1937

• Species group vittiger: most species have complex spines on the foreleg or two extra stripes over the thorax

  • Species complex davidi

  • Z. davidi Chassagnard and Tsacas, 1993
  • Z. taronus Chassagnard and Tsacas, 1993

  • Species complex indianus
    • Z. africanus Yassin and David, 2010
    • Z. gabonicus Yassin and David, 2010
    • Z. indianus Gupta, 1970
  • Species complex ornatus
    • Z. litos Chassagnard and McEvey, 1992
    • Z. ornatus Seguy, 1933
  • Species complex proximus
    • Z. capensis Chassagnard and Tsacas, 1993
    • Z. proximus Collart, 1937
  • Species complex sexvittatus: two extra stripes over first half of the thorax
    • Z. multivittiger Chassagnard, 1996
    • Z. sexstriatus Chassagnard, 1996
    • Z. sexvittatus Collart, 1937
  • Species complex vittiger
    • Z. camerounensis Chassagnard and Tsacas, 1993
    • Z. koroleu Burla, 1954
    • Z. lachaisei Yassin, 2010
    • Z. santomensis Yassin, 2008
    • Z. vittiger Coquillett, 1901