''Charaxes druceanus'', the silver-barred emperor or silver-barred charaxes, is a
butterfly
Butterflies are winged insects from the lepidopteran superfamily Papilionoidea, characterized by large, often brightly coloured wings that often fold together when at rest, and a conspicuous, fluttering flight. The oldest butterfly fossi ...
of the family
Nymphalidae
The Nymphalidae are the largest family of butterflies, with more than 6,000 species distributed throughout most of the world. Belonging to the superfamily Papilionoidea, they are usually medium-sized to large butterflies. Most species ha ...
. It is found throughout tropical
Africa
Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...
wingspan
The wingspan (or just span) of a bird or an airplane is the distance from one wingtip to the opposite wingtip. For example, the Boeing 777–200 has a wingspan of , and a wandering albatross (''Diomedea exulans'') caught in 1965 had a wingsp ...
is 55–70 mm in males and 65–85 mm in females.
''Ch. druceanus'' Btlr. is above similar to '' Charaxes phraortes'' and '' Charaxes andranodorus'', but has the basal part of the upper surface darker chestnut-brown, so that the median band is sharply defined proximally; the marginal spots of both wings are large and form on the hindwing a continuous band; the hindwing is not tailed at vein 3; the black submarginal band on both wings is considerably narrower than in ''phraortes'' and ''andranodorus''. The ground-colour of the under surface is rust-brown and the white markings have a beautiful silver gloss; the black transverse markings in the basal part of the hindwing are much reduced and only represented by fine streaks; as in ''andranodorus'' cellules 7 and 8 each have only one black spot or transverse streak, and even this may sometimes be absent; the median band of the hindwing is posteriorly much narrowed and is unicolorous or only in cellules 2—4 with a black streak at its proximal side. Congo, Angola, Nyassaland, Zambesi, Transvaal, Natal.
Biology
Its flight period is year-round.
The
larvae
A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect developmental biology, development such as insects, some arachnids, amphibians, or cnidarians typical ...
feed on various ''
Syzygium
''Syzygium'' () is a genus of flowering plants that belongs to the myrtle family, Myrtaceae. The genus comprises about 1200 species, and has a native range that extends from Africa and Madagascar through southern Asia east through the Pacific. I ...
Syzygium guineense
''Syzygium guineense'' () is an evergreen leafy forest tree of the family Myrtaceae, found in many parts of Africa both wild and domesticated. Both its fruits and leaves are edible; the pulp and the fruit skin are sucked and the seed discarded. I ...
''), ''
Bersama abyssinica
''Bersama abyssinica'' is a species of medium-sized evergreen tree in the family Francoaceae. The leaves are pinnately divided with a strongly winged rachis (hence the common name winged bersama). The inflorescence is a spike.
This species is ...
'', ''
Eugenia
''Eugenia'' is a genus of flowering plants in the myrtle family Myrtaceae. It has a worldwide, although highly uneven, distribution in tropical and subtropical regions. The bulk of the approximately 1,100 species occur in the New World tropics, ...
'' species, and ''
Astropanax goetzenii
''Astropanax'' is a genus of flowering plants in the family Araliaceae, native to Tropical Africa, Madagascar, and other Indian Ocean islands. It was resurrected from ''Schefflera
''Schefflera'' is a genus of flowering plants in the family Ar ...
''.
Notes on the biology of ''druceanus'' are given by Pringle et al (1994)
Habitat
Coastal belt and forest edges up to more than 5,000 m.
Subspecies
Listed alphabetically:
*''C. d. brazza'' Turlin, 1987 (Congo: Kinkala, Bela)
*''C. d. druceanus'' Butler, 1869 (South Africa: KwaZulu-Natal)
*''C. d. entabeni'' van Someren, 1963 (South Africa: Limpopo Province to the Zoutpansberg)
*''C. d. katamayu'' Plantrou, 1982 (Kenya: south to the area east of the Rift Valley)
*''C. d. obscura'' Rebel, 1914 ( western Uganda, Democratic Republic of the Congo, western Rwanda, western Burundi)
*''C. d. moerens'' Jordan, 1936 (South Africa: Limpopo Province and Mpumalanga, Eswatini)
*''C. d. praestans'' Turlin, 1989 (north-eastern Tanzania)
*''C. d. proximans'' Joicey & Talbot, 1922 (Democratic Republic of the Congo, eastern Angola, eastern Rwanda, eastern Burundi, southern and western Tanzania, Malawi, Zambia, north-western Zimbabwe)
*''C. d. septentrionalis'' Lathy, 1926 (eastern Uganda, western Kenya, northern Tanzania)
*''C. d. solitaria'' Henning & Henning, 1992 (South Africa: north-east and north-west slopes of the Blouberg)
*''C. d. stevensoni'' van Someren, 1963 (western Mozambique, eastern Zimbabwe)
*''C. d. teita'' van Someren, 1939 (south-eastern Kenya, Tanzania: north to the Arusha-Moshi district)
*''C. d. vivianae'' Plantrou, 1982 (Sudan: south to the Imatong Mountains)
*''C. d. williamsi'' Plantrou, 1982 (Kenya: south-east to Mount Kasigau)
Taxonomy
Curle & Curle describe a hybrid of ''Charaxes druceanus'' and ''Charaxes brutus'' Curle, A. . & Curle, N. .2004a. A description of a single male specimen of Charaxes assumed to be a hybrid of ''Charaxes brutus natalensis'' Staudinger, 1886 and ''Charaxes druceanus druceanus'' Butler, 1869 (Lepidoptera: Nymphalidae). ''Metamorphosis'' 15 (4): 165-169.
Related species
Historical attempts to assemble a cluster of presumably related species into a "''Charaxes jasius'' Group" have not been wholly convincing. More recent taxonomic revision, corroborated by phylogenetic research, allow a more rational grouping congruent with cladistic relationships. Within a well-populated
clade
In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...
of 27 related species sharing a common ancestor approximately 16 mya during the
Miocene
The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...
, 26 are now considered together as The ''jasius'' Group. One of the two lineages within this clade forms a robust
monophyletic
In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria:
# the grouping contains its own most recent co ...
group of seven species sharing a common ancestor approximately 2-3 mya, i.e. during the
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58"Out of Africa again: A phylogenetic hypothesis of the genus ''Charaxes (Lepidoptera: Nymphalidae)'' based on five gene regions" . Aduse-Poku, Vingerhoedt, Wahlberg. Molecular Phylogenetics and Evolution (2009) 53;463–478 and are considered as the ''jasius'' subgroup. The second lineage leads to 19 other species within the Jasius group, which are split into three well-populated subgroups of closely related species.
The ''jasius'' Group (26 Species):
Clade 1: ''jasius'' subgroup (7 species)
Clade 2: contains the well-populated three additional subgroups (19 species) of the jasius Group: called the ''brutus'', ''pollux'', and ''eudoxus'' subgroups.
*the ''eudoxus'' subgroup (11 species):
*'' Charaxes eudoxus''
*'' Charaxes lucyae''
*'' Charaxes richelmanni''
*''
Charaxes musakensis
''Charaxes musakensis'' is a butterfly in the family Nymphalidae. It is found in Cameroon. The habitat consists of Afromontane, montane forests at altitudes above 1,300 meters. Taxonomy
Known only from the Type (biology), type locality Musake Hut ...
Victor Gurney Logan Van Someren
Victor Gurney Logan Van Someren (1886 in Melbourne – 24 July 1976) was a zoologist and entomologist. Van Someren was born in Australia. He attended George Watson's College and studied zoology at University of Edinburgh. He was also a dentis ...
, 1963 Revisional notes on African ''Charaxes'' (Lepidoptera: Nymphalidae). Part I. ''Bulletin of the British Museum'' (Natural History) (Entomology) 195-242 *Van Someren, 1969 Revisional notes on African ''Charaxes'' (Lepidoptera: Nymphalidae). Part V. ''Bulletin of the British Museum'' (Natural History) (Entomology)75-16 Additional notes
Consortium for the Barcode of Life
The Consortium for the Barcode of Life (CBOL) was an international initiative dedicated to supporting the development of DNA barcoding as a global standard for species identification. CBOL's Secretariat Office is hosted by the National Museum of ...
Royal Museum for Central Africa
The Royal Museum for Central Africa (RMCA) (; ; ), communicating under the name AfricaMuseum since 2018, is an ethnography and natural history museum situated in Tervuren in Flemish Brabant, Belgium, just outside Brussels. It was originally b ...