Keywords

Introduction

Angola is a large country of 1,246,700 km2, notable for its great diversity of physiography, climates, habitats and resultant biodiversity). The country includes seven biomes and 15 ecoregions, ranging from equatorial rainforests of the northwest (Cabinda) and along the northern border with the Democratic Republic of Congo, through the moist miombo woodlands and savannas of the central plateaus, to the dry forests and woodlands of the southeast, and to the arid shrublands and Namib Desert of the southwest. Isolated forests with Congolian affinities are found along the Angolan Escarpment, and similar remnant patches of Afromontane forests are found on some of the highest mountains such as Mount Moco and Mount Namba.

Despite the fact that at the beginning of the nineteenth century only a few species of butterflies and skippers (Insecta: Lepidoptera: Papilionoidea) were recorded from Angola, today a large number of taxa (at least 792 species and subspecies: Fig. 10.1, Table 10.1 and Appendix) are known to occur in the country. However, extensive areas are still poorly surveyed for butterflies, or have not been surveyed at all (Fig. 10.2). This applies in particular to the southern provinces of Namibe, Cunene and Cuando Cubango and the northwestern province of Zaire as well as most of southern Moxico. Furthermore, the Baixa de Cassanje (Malanje), separated from surrounding areas by steep escarpments, appears to have distinctive vegetation and may produce some interesting butterflies. Although most of the localities where butterflies and skippers have been collected in Angola have been determined (Mendes et al. 2013b), some localities previously reported for a few species remain untraced despite searches by us, using the detailed maps of the Junta de Investigações do Ultramar (JIU 1948–1963).

Fig. 10.1
figure 1

Cumulative number of species/subspecies of Papilionoidea reported from Angola from 1801–1819 (first records) to the recent decade – 2011–2017 – according to Appendix. For practical reasons, species which first reference to the country was untraceable (marked in Appendix with a ▲) were included in the decade 2001–2010; species that are now assigned as faunistic novelties to Angola (marked in Appendix with a ◘) are included in the last decade (2011–2017)

Table 10.1 Number of species of Papilionoidea families and subfamilies known to occur in the Afrotropical Region and Angola (with % of Afrotropical species present in the country), and number of species endemic to Angola (with % of endemism shown)
Fig. 10.2
figure 2

Map of Angola showing, marked in orange, the known areas surveyed for the Papilionoidea from the beginning of their study, in the nineteenth century to the present day – each square ca. 33 × 33 km. The collecting pressure varies across the country, from ‘squares’ where samples were obtained only once, in passing, to others where the collectors were based for months

The accumulation of knowledge in regard to Angolan butterflies has been constrained by several factors. The two largest Angolan entomological collections, deposited in the Museu do Dundo (Lunda-Norte) and in the Instituto de Investigação Agronómica (Huambo), have never been studied in detail. In addition little fieldwork was carried out in Angola during the post-independence period because of the protracted civil war. Finally, the vastness of the country and the difficulty in accessing many remote regions has impeded progress.

Until recently the Hesperiidae (skippers) were placed in the superfamily Hesperioidea, separate from the rest of the butterflies, which were placed in the superfamily Papilionoidea. However, today the skippers and butterflies are all placed in the Papilionoidea (e.g. Heikkilä et al. 2012). The classification used for butterflies in this chapter is based on Williams (2018), Espeland et al. (2018) and Dhungel and Wahlberg (2018). Six families of butterflies are represented in Angola, namely Papilionidae, Hesperiidae, Pieridae, Riodinidae, Lycaenidae and Nymphalidae.

History of Research on the Papilionoidea of Angola

The first known reference to butterflies obtained in Angola is by Latreille and Godart (1819), who reported the presence of Colotis euippe (Linnaeus, 1758) and described Acraea parrhasia servona. In the decade between 1871 and 1880, Druce (1875) reported about 90 species from Angola for the first time, a number of these being descriptions of species new to science. By the end of the nineteenth century a total of 214 butterfly taxa were known from Angola.

The first contributions to our knowledge of Angolan butterflies by Portuguese researchers were only made in the middle nineteen hundreds. These were the result of the activities in Angola of the Centro de Zoologia (CZ) of the Junta de Investigações do Ultramar, coordinated by its first director Fernando Frade. In 2014 this research institution was renamed the Instituto de Investigação Científica Tropical (IICT). Working from these large zoological collections, as well as from further specimens obtained in Angola by Amélia Bacelar (1948, 1956, 1958a, b, 1961) and Miguel Ladeiro (1956), considerably expanded the list of Angolan butterflies. Most of this material, obtained during colonial times, was stored in Lisbon, with corrections to the published identifications only being made recently. All of this material has now been integrated into the collections of the Museu Nacional de História Natural e da Ciência (MUHNAC). Albert Monard (1956) of the La Chaux-de-Fonds Swiss Museum also studied other material obtained by the CZ missions. Significant contributions in the twentieth century were also made by Weymer (1901) on the southern Angolan species, and by Evans (1937) on the Hesperiidae. All of the then known Angolan butterflies were listed by Aurivillius (in Seitz) in 1928. All of the Angolan Charaxinae were dealt with by Henning in his 1988 book on the African taxa of this family. The 339 taxa added to the faunal list during the twentieth century brought the total to 553 known butterfly taxa for Angola.

During the first 18 years of the twenty-first century, 239 further taxa were added to the total. In the first decade of the present century, most of the new information was due to several contributions by Libert (1999, 2000, 2004) on the Lycaenidae, and by Gardiner (2004). The latter author listed taxa from the southeastern Cuando Cubango province, which borders the Caprivi Strip of Namibia. Cuando Cubango and the easternmost province of Moxico are the only provinces in Angola with Zambezian fauna. To these taxa we add our own contributions (Bivar-de-Sousa and Mendes 2006, 2007, 2009a, b; Mendes and Bivar-de-Sousa 2006a, b, 2007a, b, 2009a, b, c, d). Over the last 8 years 33 species were described as new or recorded for the first time from Angola by Mendes and Bivar-de-Sousa (2012, 2017) Mendes et al. (2013a, 2017, 2018), Bivar-de-Sousa and Mendes (2014) and Bivar-de-Sousa et al. (2017), Turlin and Vingerhoedt (2013) and Pierre and Bernaud (2013). Finally, 66 further taxa are now recorded as faunistic novelties for the country (Appendix). The current total number of butterfly taxa for Angola now stands at 792.

Sources Consulted for the Checklist

In preparing this revised checklist of the Papilionoidea, the following collections of Angolan butterflies held by institutions in Portugal were examined: Museu Nacional de História Natural e da Ciência (MUHNAC) in Lisbon, Museu de História Natural da Universidade do Porto (MHNC-UP), Liceu Nun’Álvares in the Caldas da Saúde and the Singeverga Order of St Benedict Abbey in Areias. Major contributions to these collections were made by A Bivar-de-Sousa (Luanda district and Cuanza-Norte, Cuanza-Sul and Moxico Provinces), António Figueira, (northwestern Angola), Mário Macedo (northern Angola), Passos de Carvalho (Huambo and Cuanza-Norte Provinces), Carneiro Mendes and Pessoa Guerreiro. The Angolan insect collection of Nozolino de Azevedo (mainly Huambo Province), maintained and made available by his widow, was also studied.

The collections in the MUHNAC in Lisbon were destroyed by a fire in March 1978. However, prior to the fire BS had studied some of the material and published his findings. In 1995 LM studied the collections, mainly of Barros Machado and Luna de Carvalho, in the Dundo Museum in Angola but there was insufficient time to do a detailed analysis. We did not inspect the entomological collections in the former Instituto de Investigação Agronómica de Angola, collected mainly by Passos de Carvalho, but they are apparently in good condition. No entomological collections were found by LM, in 1995 and 2013, at the Museu de História Natural de Luanda. Material collected from 2010 to 2014 by Ruben Capela and Carmen Van-Dúnen Santos of Agostinho Neto University, Luanda and Artur Serrano of the Faculty of Sciences, Lisbon University, was examined by us.

In addition, images of live specimens published by Lautenschläger and Neinhhuis (2014) were examined, as were several images presented by Jorge Palmeirim of Lisbon University and Pedro Vaz Pinto of the Kissama Foundation.

Taxa Excluded from the Checklist

A number of taxa have erroneously been reported to occur in Angola. This was due mainly to probable misidentifications or mislabelled specimens. Some older records are omitted because the known range of the taxon is unlikely to include Angola. A list of the omitted taxa is given below.

  • Hesperiidae: Eretis djaelaelae (Wallengren, 1857), Metisella metis (Linnaeus, 1764), Kedestes chaca (Trimen, 1873), Platylesches chamaeleon (Mabille, 1891).

  • Papilionidae: Papilio menestheus Drury, 1773, Graphium taboranus (Oberthür, 1886), Graphium (Arisbe) junodi (Trimen, 1893).

  • Pieridae: Eurema brigitta (Stoll, 1780), Colotis chrysonome (Klug, 1829), Colotis ephyia (Klug, 1829), Belenois theora (Doubleday, 1846), Mylothris rubricosta (Mabille, 1890), Mylothris similis Lathy, 1906.

  • Lycaenidae: Telipna acraea (Westwood, 1851), Cooksonia abri Collins & Larsen, 2008, Mimacraea darwinia Butler, 1872, Liptena bassae Bethune-Baker, 1926, Aethiopana honorius honorius (Fabricius, 1793), Stempfferia uniformis (Kirby, 1887), Stempfferia dorothea (Bethune-Baker, 1904), Oxylides faunus (Drury, 1773), Dapidodigma hymen (Fabricius, 1775), Aloeides molomo (Trimen, 1870), Leptomyrina lara (Linnaeus, 1764), Deudorix livia (Klug, 1834), Neurellipes onias (Hulstaert, 1924), Zintha hintza (Trimen, 1864).

  • Riodinidae: Afriodinia caeca semicaeca (Riley, 1932), Afriodinia gerontes (Fabricius, 1781).

  • Nymphalidae: Bicyclus milyas (Hewitson, 1864), Ypthima congoana Overlaet, 1955, Charaxes jahlusa argynnides Westwood, 1864, Junonia touhilimasa Vuillot, 1892, Neptis continuata Holland, 1892, Neptis strigata Aurivillius, 1894, Evena oberthueri (Karsch, 1894), Euriphene atrovirens (Mabille, 1878), Bebearia mardania (Fabricius, 1793), Euphaedra morini Hecq, 1983, Euphaedra xypete (Hewitson, 1865), Euphaedra campaspe (Felder & Felder, 1867), Euphaedra inanum (Butler, 1873), Euphaedra eupalus (Fabricius, 1781).

A Revised Checklist of the Papilionoidea of Angola

A revised and annotated checklist of the Papilionoidea of Angola (Appendix) confirms the presence of at least 792 taxa in the country. Their presence is based mainly on verification by the authors of this chapter. Some taxa, recorded by other authors, are accepted because they were, with rare exceptions, reported by more than one author, are based on reliable literature records, or because Angola falls within their putative geographical range. In the Checklist, the first reference to their occurrence in Angola is given, followed by the sources of validation of the record and their preferred habitat(s). Occasionally more than one subspecies of a particular species occurs in the country. This is due to both the size and ecological diversity of Angola. A number of forests, especially gallery-forests, are independent of each other as are the fragmented forests of the Angolan Escarpment. In addition, the southeastern parts of Moxico and the Cuando Cubango provinces are part of the Zambesi Basin; consequently their fauna has affinities with that of eastern Africa.

As far as habitats are concerned the great majority of the Angolan Papilionoidea, as might be expected, occur in forest, both wet and dry (Appendix). However, the Hesperiidae and Pieridae appear to be almost as diverse in moist woodland (miombo) and dry woodland as they are in forest. The number of Pieridae in dry woodland and miombo is similar, while the number of species in dry woodland, arid shrubland and grassland surpasses that of wet forest. The subfamily Nymphalinae is more diverse in miombo than forest and equally diverse in savanna. The Heliconiinae (Nymphalidae) in savanna are almost as diverse as they are in wet forest.

Composition, Diversity and Endemism

All six families and all of the subfamilies (except the Lycaeninae, Leach, 1815) of Afrotropical butterflies are represented in Angola (Table 10.1).

One genus and 56 species/subspecies of Papilionoidea are endemic to Angola, many of which were described over the last few decades. The endemic genus Mashunoides, Mendes and Bivar-de-Sousa 2009a, b, c, d (Nymphalidae: Satyrinae) is confined to Cuando Cubango Province, in the ecotone between miombo and savanna/dry woodland mosaic. Endemism rates for Angolan butterfly families are highest for the Papilionidae and Lycaenidae and lowest for the Hesperiidae and Riodinidae (Tables 10.1 and 10.2). Examples of endemic species are illustrated in Fig. 10.3.

Table 10.2 Endemic butterfly species and subspecies in Angola
Fig. 10.3
figure 3

The holotype specimens of endemic Angolan papilionoidea: Left to right, top to bottom (V Ventral, D Dorsal): 1. Abantis bergeri male D (Mendes and Bivar-de-Sousa 2009a, b, c, d), 2. Eagris multiplagata male V (Bivar-de-Sousa and Mendes 2007), 3. Cooksonia nozolinoi female D (Mendes and Bivar-de-Sousa 2007), 4. Papilio bacelarae male D (Bivar-de-Sousa and Mendes 2009a, b), 5. Mashunoides carneiromendesi male V (Mendes and Bivar-de-Sousa 2009a, b, c, d), 6. Charaxes jahlusa angolensis male D (Mendes et al. 2017), 7. Euxanthe trajanus bambi male D (Bivar-de-Sousa and Mendes 2006), 8. Euphaedra (Euphaedrana) divoides male V (Bivar- de-Sousa and Mendes 2018)

Conservation

Because butterflies are sensitive to changing environmental conditions and are taxonomically well known, they are valuable as indicators of ecological dynamics. They are also key drivers of ecological processes. In particular, adult butterflies are active pollinators of many plants and the imagos and larvae are an important source of nutrition for a diverse range of vertebrate and invertebrate predators and insect parasitoids. Their conservation importance is also due to their positive and occasionally negative economic impacts. Although humans utilise mainly moth caterpillars as a food source, the larvae of the skipper Coeliades libeon is much appreciated. A limited number of butterfly species are agricultural pests, including Papilio demodocus (young citrus orchards), Lampides boeticus (cultivated Leguminosae) and Acraea acerata (sweet-potatoes). A few species, such as Pyrrhochalcia iphis and Zophopetes dysmephila, may cause damage in coconut and oil-palm plantations.

In terms of species of conservation concern, information on the status of Angolan butterflies is very limited. Many species of Angolan butterflies are obviously abundant and widespread, both within and outside the country. Those taxa that appear to be rare and/or more localised may be genuinely rare or local but this may simply reflect a paucity of information. This makes it difficult or impossible to propose rational conservation measures at present. The urgent need for more fieldwork, particularly in regard to the endemic taxa, is thus highlighted. In the meantime habitat conservation, especially with respect to isolated forest patches, can be considered as part of a wider effort to conserve both the fauna and flora of the country.

Potential Future Discoveries and Research

Considering the number of taxa new to science described in the last few decades there are almost certainly further undiscovered butterfly taxa in Angola. Vast areas of the country remain unexplored, mainly because of inaccessibility and post-independence political instability. Not only will new taxa be found but also known taxa from bordering countries will be added to the list of Angolan butterflies during future fieldwork. This work will also improve our knowledge in regard to the distribution of the taxa in the country. Finally, almost nothing is known about the habitats, behaviours, early stages and larval host plants of Angolan butterflies, making these fertile areas for future research on the fauna. More information concerning all the endemic taxa is urgently needed in order to determine conservation priorities.