Acraea (butterfly)


Acraea is a genus of brush-footed butterflies of the subfamily Heliconiinae. It seems to be highly paraphyletic and has long been used as a "wastebin taxon" to unite about 220 species of anatomically conservative Acraeini. Some phylogenetic studies show that the genus Acraea is monophyletic if Bematistes and Neotropical Actinote are included. Most species assembled here are restricted to the Afrotropical realm, but some are found in India, Southeast Asia, and Australia.

Biology

The eggs are laid in masses; the larvae are rather short, of almost equal thickness throughout, and possessing branched spines on each segment, young larvae group together on a protecting mass of silk; the pupa is slender, with a long abdomen, rather wide and angulated about the insertion of the wings, and suspended by the tail only. A. horta, A. cabira, and A. terpsicore illustrate typical life histories.
The food plants of Acraea caterpillars are usually Urticaceae or, like in most Heliconiinae, Passifloraceae. Some feed on other plants, such as Fabaceae, "Flacourtiaceae", or Violaceae. Their preferred species contain cyanogenic glycosides, 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. Their flight is slow and flapping.

Systematics and taxonomy

That all these species were properly placed in Acraea has never been generally accepted. In 1807, Johan Christian Fabricius 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 Acraeini.
With increasing availability of DNA sequence 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 in 1819 suggested to separate species around Acraea serena as Telchinia. This name has been applied to a generally African group whose members usually feed on Urticaceae, and they had already been noted to bear some uncanny resemblances to the American Actinote 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 and are at least in part quite close relatives of the African genus Bematistes. 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—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 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 Indian 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. For this, the name A. eponina, from the Papilio eponina established in the 1780 issue of Pieter Cramer's De uitlandsche Kapellen, had been used all the time. Another instance of the confusion rife in this genus is exemplified by Boisduval's Acraea manjaca.
These developments come from two papers written by J. Pierre and D. Bernaud.

Species

Since the proposed phylogenetic sequence of the species groups is almost certainly incorrect for a large part, the groups are simply listed alphabetically.
J. Pierre & D. Bernaud have published a complete systematic and synonymic list.
Acraea acrita species groupAcraea acrita – fiery acraeaAcraea annonaeAcraea bellonaAcraea chaeribulaAcraea eltringhamianaAcraea guluensisAcraea loranaeAcraea lualabaeAcraea mancaAcraea pudorina – Kenyan fiery acraeaAcraea utengulensis – Tanzanian fiery acraea
Acraea andromacha species group Acraea andromacha – small greasy, glasswing
Acraea anemosa species groupAcraea anemosa – broad-bordered acraeaAcraea pseudolyciaAcraea turna
Acraea aureola species groupAcraea aureola
Acraea bonasia species group Acraea acerata – small yellow-banded legionnaire, falls acraea Acraea aliciaAcraea bonasiaAcraea burgessiAcraea cabira – yellow-banded acraeaAcraea serena – dancing acraeaAcraea eponina – orange acraea or small orange acraea Acraea excelsiorAcraea goetzeiAcraea karschiAcraea lumiriAcraea rangatanaAcraea hecquiAcraea pierreiAcraea sotikensis – Sotik acraea, Sotika legionnaireAcraea uvui – tiny acraeaAcraea ventura
Acraea caecilia species group
[file:Acraea natalica, m (bo) & w, Skrikfontein, d.jpg|thumb|right|Natal legionnaires (A. natalica)]Acraea aglaonice – clear-spotted acraeaAcraea mirabilis – marvelous acraeaAcraea miranda – desert acraea, Somali acraeaAcraea asboloplintha – black-winged acraea, black-winged legionnaireAcraea atergatisAcraea atatisAcraea axina – little acraeaAcraea braesiaAcraea caecilia – pink legionnaire Acraea caldarena – black-tipped acraea, black tip acraeaAcraea doubledayiAcraea ellaAcraea equatorialisAcraea intermediodesAcraea leucopygaAcraea lygus – lygus acraeaAcraea marnois Acraea natalica – Natal acraea, Natal legionnaireAcraea oncaea – window acraea, window legionnaireAcraea pseudeginaAcraea pudorellaAcraea rhodesianaAcraea stenobea – suffused acraeaAcraea lyciAcraea sykesi – Sykes' acraea
Acraea cepheus species group Acraea abderaAcraea asemaAcraea atolmisAcraea bailundensisAcraea buettneriAcraea cepheusAcraea bergerianaAcraea chambeziAcraea diogenesAcraea guillemeiAcraea lapidorumAcraea lofuaAcraea mansyaAcraea nohara – light red acraeaAcraea dondoensisAcraea onerataAcraea periphanesAcraea petraea – blood-red acraea, blood acraeaAcraea punctellataAcraea rohlfsiAcraea violarum – speckled red acraea
Acraea circeis species group Acraea buschbeckiAcraea circeis – white legionnaire Acraea conradtiAcraea grosvenoriAcraea kuekenthaliAcraea melanoxanthaAcraea newtoniAcraea ntebiaeAcraea oreasAcraea orina – Orina legionnaireAcraea orinataAcraea parrhasia – yellow-veined legionnaireAcraea pelopeiaAcraea peneleosAcraea penelope – Penelope's acraea, Penelope's legionnaireAcraea perennaAcraea semivitrea Acraea translucidaAcraea ungemachiAcraea vumbui
Acraea egina species group Acraea egina – elegant legionnaire Acraea medea
Acraea encedon species group – common acraea or white-barred acraea or encedon acraeaAcraea encedana – Pierre's acraea Acraea encedon – common acraea, white-barred legionnaire Acraea necodaAcraea encoda
Acraea issoria species group Acraea issoria – yellow coster
Acraea jodutta species group Acraea actinotinaAcraea acutaAcraea alciopeAcraea alciopoidesAcraea amicitiaeAcraea ansorgeiAcraea aurivilliiAcraea baxteriAcraea disjunctaAcraea esebria – dusky acraeaAcraea comorAcraea insularisAcraea jodutta – jodutta legionnaireAcraea johnstoniAcraea lycoa – lycoa legionnaire Acraea masarisAcraea niobeAcraea safie
Acraea masamba species group Acraea aubyni – Aubyn Rogers' acraeaAcraea cinerea – grey acraeaAcraea fornaxAcraea igola – dusky-veined acraeaAcraea masambaAcraea quirinalisAcraea sambavaeAcraea silianaAcraea simulata Acraea strattipocles
Acraea oberthuri species group Acraea althoffi – Althoff's acraeaAcraea bergeriAcraea oberthueriAcraea pseudepaea
Acraea pentapolis species group Acraea pentapolis – musanga legionnaireAcraea vesperalisAcraea obeiraAcraea burni – pale-yellow acraea Acraea orestiaAcraea lia
Acraea pharsalus species group Acraea pharsalus – familiar legionnaireAcraea vuilloti
Acraea rahira species group Acraea anacreon – large orange acraea, orange acraea Acraea anacreonticaAcraea bombaAcraea calidaAcraea guichardiAcraea lusingaAcraea induna – induna acraea Acraea kadunaAcraea pareiAcraea alalonga – long-winged orange acraea Acraea mirificaAcraea rahira – marsh acraeaAcraea speciosaAcraea wigginsiAcraea zitja
Image:Acraea horta00.jpg|thumb|right|Garden acraea pupa and caterpillar
Acraea satis species groupAcraea rabbaiae – clear-wing acraea, clearwing legionnaireAcraea satis – east coast acraeaAcraea zonata
A. terpsicore groupAcraea admatha – Hewitson's glassy legionnaireAcraea boopis – rainforest acraeaAcraea endoscota Acraea kappaAcraea kiaAcraea kinduanaAcraea camaena Acraea cuvaAcraea dammiiAcraea eltringhamiAcraea eugeniaAcraea hamataAcraea horta – garden acraea Acraea hovaAcraea igati Acraea insignisAcraea leucographaAcraea machequena – machequena acraeaAcraea mahelaAcraea matuapaAcraea neobule – wandering donkey acraea, wandering donkey Acraea braineiAcraea quirina – common glassy legionnaire Acraea ranavalona Acraea rileyiAcraea rogersi – Rogers's large legionnaire Acraea serena – dancing acraea, small orange legionnaire
Acraea terpsicore species group Acraea terpsicore – tawny coster
Acraea zetes species group Acraea acara – acara acraeaAcraea barberi – Barber's acraeaAcraea chiloAcraea hypoleucaAcraea magnificaAcraea trimeni – Trimen's acraeaAcraea zetes
Species group undeterminedAcraea acutipennisAcraea alticolaAcraea cerasa – tree top acraeaAcraea ducarmei Acraea humilisAcraea kalinzuAcraea kraka – kraka glassy acraeaAcraea macaristaAcraea mimaAcraea odzalaeAcraea omroraAcraea oscariAcraea overlaetiAcraea peetersiAcraea polis Acraea pseudatolmisAcraea pullulaAcraea punctimargineaAcraea siliaAcraea simulatorAcraea iturina – Ituri glassy acraeaAcraea torunaAcraea turliniAcraea vivianaAcraea zoumi
Some other species formerly in Acraea have now been definitely assigned to other genera, e.g. Bematistes.