Acraea is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of brush-footed butterflies (family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Nymphalidae) of the subfamily Heliconiinae

Heliconiinae

The Heliconiinae, commonly called heliconians or longwings, are a subfamily of the brush-footed butterflies . They can be divided into 45-50 genera and were sometimes treated as a separate family Heliconiidae within the Papilionoidea...

. It seems to be highly paraphyletic and has long been used as a "wastebin taxon

Wastebin taxon

Wastebasket taxon is a term used in some taxonomic circles to refer to a taxon that has the sole purpose of classifying organisms that do not fit anywhere else. They are typically defined by their lack of one or more distinct character states or by their not belonging to one or more other taxa...

" to unite about 220 species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of anatomical

Anatomy

Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...

ly conservative Acraeini

Acraeini

Acraeini is a tribe of butterflies of the subfamily Heliconiinae in the family Nymphalidae.-Genera:* Abananote Potts, 1943* Acraea – acraeas* Actinote* Altinote Potts, 1943* Bematistes* Cethosia – lacewings...

. Most species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 assembled here are restricted to the 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...

n region, but some are found in 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...

, 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...

, and Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

.

The foodplants of their caterpillar

Caterpillar

Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...

s are usually Urticaceae

Urticaceae

Urticaceae, or the nettle family, is a family of flowering plants. The family name comes from the genus Urtica . Urticaceae includes a number of well-known and useful plants, including the aforementioned nettles, Ramie , māmaki , and ajlai .The family includes approximately 2600 species, grouped...

 or, like in most Heliconiinae, Passifloraceae

Passifloraceae

Passifloraceae is a family of flowering plants, containing about 530 species classified in around 18 genera. They include trees, shrubs, lianas and climbing plants, and are mostly found in tropical regions....

. Some feed on other plants, such as Fabaceae

Fabaceae

The Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, is a large and economically important family of flowering plants. The group is the third largest land plant family, behind only the Orchidaceae and Asteraceae, with 730 genera and over 19,400 species...

, "Flacourtiaceae

Flacourtiaceae

Flacourtiaceae is a defunct family of flowering plants whose former members have been scattered to various other families, mostly to Achariaceae, Samydaceae, and Salicaceae. It was so vaguely defined that hardly anything seemed out of place there and it became a dumping ground for odd and anomalous...

" or Violaceae

Violaceae

Violaceae are a family of flowering plants consisting of about 800 species in 21 genera. It takes its name from the genus Viola, the violets and pansies.Older classifications such as the Cronquist system placed Violaceae in an order named after it, the Violales...

. Their preferred species contain cyanogenic glycoside

Glycoside

In chemistry, a glycoside is a molecule in which a sugar is bound to a non-carbohydrate moiety, usually a small organic molecule. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. These can be activated by enzyme...

s, which make the larvae and adults poisonous to predators. The aposematic coloration of the adults announces this, and some species are mimicked by less noxious butterflies. At least some "Acraea" are able to produce the toxins themselves.

Systematics and taxonomy

That all these species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 were properly placed in Acraea has never been generally accepted. In 1807, Johan Christian Fabricius

Johan Christian Fabricius

Johan Christian Fabricius was a Danish zoologist, specialising in "Insecta", which at that time included all arthropods: insects, arachnids, crustaceans and others...

 established the genus for the Garden Acraea, described as Papilio horta by Carl Linnaeus in 1764, and its relatives. By and by, an increasing number of species were placed here. As early as 1848, and again in 1887 and the early 1990s, it was attempted to divide the genus into groups of closest relatives, as it was suspected that some "Acraea" might actually be closer to other genera in the tribe

Tribe (biology)

In biology, a tribe is a taxonomic rank between family and genus. It is sometimes subdivided into subtribes.Some examples include the tribes: Canini, Acalypheae, Hominini, Bombini, and Antidesmeae.-See also:* Biological classification* Rank...

 Acraeini

Acraeini

Acraeini is a tribe of butterflies of the subfamily Heliconiinae in the family Nymphalidae.-Genera:* Abananote Potts, 1943* Acraea – acraeas* Actinote* Altinote Potts, 1943* Bematistes* Cethosia – lacewings...

.

With increasing availability of DNA sequence

DNA sequence

The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...

 data, it is confirmed that Acraea as loosely defined does not constitute a monophyletic group. Even before the attempts to split up Acraea in earnest had begun, Jacob Hübner

Jacob Hübner

Jacob Hübner was a German entomologist. He was the author of Sammlung Europäischer Schmetterlinge , a founding work of entomology.-Scientific career:...

 in 1819 suggested to separate species around Acraea serena as Telchinia. This name has been applied to a generally 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...

n group whose members usually feed on Urticaceae

Urticaceae

Urticaceae, or the nettle family, is a family of flowering plants. The family name comes from the genus Urtica . Urticaceae includes a number of well-known and useful plants, including the aforementioned nettles, Ramie , māmaki , and ajlai .The family includes approximately 2600 species, grouped...

, and they had already been noted to bear some uncanny resemblances to the American

Americas

The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...

 Actinote

Actinote

Actinote is a genus of butterflies from South America of the subfamily Heliconiinae in the family Nymphalidae. For taxonomic problems regarding this group, see Acraea.-Species:*thallia species-group**Actinote alalia Actinote is a genus of butterflies from South America of the subfamily Heliconiinae...

in anatomical details. Indeed, they seem to be closer relatives of these than of the other butterflies placed in Acraea, which usually feed on Passifloraceae

Passifloraceae

Passifloraceae is a family of flowering plants, containing about 530 species classified in around 18 genera. They include trees, shrubs, lianas and climbing plants, and are mostly found in tropical regions....

 and are at least in part quite close relatives of the African genus Bematistes

Bematistes

Bematistes is a genus of butterflies in the family Nymphalidae.-Species:*umbra species-group:**Bematistes adrasta **Bematistes aganice **Bematistes alcinoe...

. Those closest to that genus might warrant separation as Rubraea or Stephenia.

But while several informal "species groups" have been established, it is not clear which of these are monophyletic and how to split the apparently still paraphyletic genus further. The placement of the Garden Acraea -- the type species

Type species

In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

 -- and hence which of the any further subdivisions will get to bear the name Acraea, remains unresolved. As it is traditionally included in the former A. terpsicore group (now A. serena group) and its caterpillars, while polyphagous, do not feed on Urticaceae, it may be that the separation of Telchinia is unwarranted and other proposed genera might be resurrected instead.

There was one major misidentification which still causes confusion today. Acraea terpsicore, described as Papilio terpsicore by Linnaeus in 1758, was held to be the senior synonym of A. serena, described by Fabricius as Papilio serena in 1775. Hence, the former name was commonly used for that African species. But as it turned out, Linnaeus had actually described an 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...

n species -- the well-known Tawny Coaster. Fabricius in 1793 believed it was new to science and described it again, as Papilio violae. Consequently it had been long known as A. violae. It was also recognized that Fabricius' little-studied P. serena was none other than the Orange Acraea

Orange Acraea

Orange Acraea is a name applied to two butterflies of tropical Africa and adjacent Arabia:* Acraea alalonga , restricted to northeastern South Africa...

. For this, the name A. eponina, from the Papilio eponina established in the 1780 issue of Pieter Cramer

Pieter Cramer

Pieter Cramer , was a wealthy Dutch merchant in linen and Spanish wool, and an entomologist. Cramer was the director of the Zealand Society, a scientific society located in Flushing and a member of Concordia et Libertate, based in Amsterdam...

's De uitlandsche Kapellen, had been used all the time.

The publication which have restored the good name of serena is the following one:
- Bernaud & Pierre, 1999. - Acraea serena (Fabricius, 1775) (=A. eponina Cramer, 1780), problème de nomenclature et premiers états (Lepidoptera, Nymphalidae). Bull. Soc. Ent. Fr. 104 (4): 357-364

Species

Since the proposed phylogenetic sequence of the "species groups" is almost certainly incorrect for a large part, the groups are simply listed alphabetically.
Acraea acrita species group

• Acraea acrita
  Acraea acrita
  The Fiery Acraea is a butterfly of the Nymphalidae family. It is found in large parts of Africa.The wingspan is 45–55 mm...
  
  – Fiery Acraea
• Acraea chaeribula
• Acraea eltringhamiana
• Acraea guluensis
• Acraea lualabae
• Acraea manca
• Acraea pudorina – Kenyan Fiery Acraea
• Acraea utangulensis – Tanzanian Fiery Acraea

Acraea andromacha species group (close to part of A. serena group?)

• Acraea andromacha
  Acraea andromacha
  The Glasswing or Small Greasy is a butterfly of the Nymphalidae family. It is found in Australia, New Guinea and surrounding islands...
  
  – Small Greasy, "glasswing"

Acraea anemosa species group

• Acraea anemosa
  Acraea anemosa
  The Broad Bordered Acraea is a butterfly of the Nymphalidae family. It is found in Zululand, Swaziland, Transvaal, Zimbabwe, Mozambique, Malawi, Zambia, southern Zaire , Namibia, Angola, Tanzania, the coast of eastern Kenya and southern Somalia.It is a variable species with a number of described...
  
  – Broad-bordered Acraea
• Acraea pseudolycia
• Acraea turna

Acraea aureola species group

• Acraea aureola