Maputaland-Pondoland-Albany, one of the African biodiversity hotspots, is defined by a high diversity of its fauna and flora. Despite numerous studies published about the Lepidoptera of this region, our knowledge of diversity and distributional patterns of moths still remains inadequate. Our study evaluates the tussock moth richness and endemism of the wider Maputaland-Pondoland-Albany region. We describe for the first time the variety of the tussock moth fauna of Mozambique, with seven newly recorded genera (Euproctoides Bethune-Baker, 1911; Heteronygmia Holland, 1893; Leucoma Hübner, 1822; Ogoa Walker, 1856; Paraproctis Bethune-Baker, 1911; Polymona Walker, 1855; Tamsita Kiriakoff, 1954).

Biodiversity hotspots are defined as highly threatened biogeographic regions with the occurrence of endemic species of animals and plants (Myers 1988). Containing approximately half of the world’s plant and a significant percentage of world’s vertebrate diversity (Myers et al. 2000), conservation and thorough investigation of these 35 remarkable regions distributed worldwide became essential for many researchers due to ongoing species mass extinction (Mittermeier et al. 2011; Eisenhauer et al. 2019). The majority of the African hotspots are located in the Afrotropics (Myers et al. 2000). Maputaland-Pondoland-Albany is one of the three recently recognized biodiversity hotspots in the region of southern Africa (Fig. 1). Diversity and endemism are focused in the three major units: Maputaland in the north, Pondoland in the south and Albany in the south-west, comprising fauna and flora of South Africa, Eswatini (Swaziland) and Mozambique (Perera et al. 2011). The dominant habitats of this region bearing the most unique diversity are tropical and subtropical moist broadleaf forests and mountain grasslands and scrublands. Despite the uniqueness of this area serving as a meeting point for six of the eight southern African biomes, only 25% of the original extent of the natural habitat remains preserved (Mittermeier et al. 2004).

Figure 1. 

Map of the studied area, modified from Weller et al. (2017). The area of the Maputaland-Pondoland-Albany is highlighted by lighter colour.

The moth subfamily Lymantriinae (Noctuoidea, Erebidae) occurs worldwide and comprises more than 2600 species in almost 360 genera (Kitching and Rawlins 1998). South Africa can be considered a well-studied part of the Maputaland-Pondoland-Albany, with several studies discussing the tussock moth fauna (Hampson 1905 – 77 spp., Janse 1917 – 109 spp., Pinhey 1975 – 57 spp., Vári et al. 2002 – 187 spp., Staude et al. 2020 – 34 spp.). However, knowledge of the Lymantriinae of the other southern African countries remains fairly insufficient. Presently, approximately 50 species of tussock moths are known to occur in Eswatini (Duke et al. 1999) and five species are reported from Lesotho (Kopij 2006). The current knowledge of the fauna of Mozambique is based mainly on past taxonomic works carried out on museum materials (e.g., Collenette 1955) counting roughly 50 species. Nonetheless, previously published works also include numerous mistakes in systematics (e.g., published synonyms, identification errors, etc.) and creates “ghost” diversity.

The purpose of this study was to provide an up-to-date overview and fill the gaps in the poor knowledge in the diversity of tussock moths of Afrotropical biodiversity hotspots. Verified distribution data also recovers potential endemic species and thus plays a significant role in the global conservation effort. In addition, we provide a first faunistic summary of the tussock moths of Mozambique, recording seven genera new to the country.

For the compilation of the list of Lymantriinae of the wider Maputaland-Pondoland-Albany we used presence/absence datasets covering the fauna of South Africa, Lesotho, Eswatini and Mozambique (Table 1). The data were mined from literature (e.g., Vári et al. 2002), corrected and supplemented by data obtained by the revision of the following museum collections: African Natural History Research Trust (Leominster, United Kingdom), Natural History Museum (London, United Kingdom), Museum Witt (Munich, Germany), Bavarian State Collection of Zoology (Munich, Germany), and Naturalis Biodiversity Centre (Leiden, Netherlands). In total 2352 specimens from South Africa, 2079 specimens from Mozambique, 18 specimens from Lesotho and 61 specimens from Eswatini were revised. The specimens were photographed using a Nikon D90 camera with Nikkor AF Micro 60 mm lens and assembled for our plates using the Corel DRAW X7 computer program.

We compared the faunal diversity of the regions using number of species, and similarity or uniqueness of the species composition expressed as a nestedness of the species and species turnover expressed as binary presence/absence data. We calculated the data in R v. 4.0.3. (R Core Team 2018), by a command “nestedbetajac” (package vegan – Oksanen et al. 2019). Species endemicity was evaluated based on the data of species occurrence available from online database (De Prins and De Prins 2021) and from literature (e.g., Swinhoe 1903).

We reported altogether 168 species of tussock moths belonging to 43 genera currently occurring in the Maputaland-Pondoland-Albany biodiversity hotspot. We are listing 158 species from South Africa, 62 species from Mozambique, 48 species from Eswatini and 10 species from Lesotho. The faunal comparison analysis also revealed 44 potentially endemic species from South Africa and six potentially endemic species from Mozambique (Table 1). By the term “potential endemic species” we mean a species reported so far from only one country, but we cannot rule out its distribution in surrounding countries.

The following genera are recorded for the first time from Mozambique: Euproctoides Bethune-Baker, 1911; Heteronygmia Holland, 1893; Leucoma Hübner, 1822; Ogoa Walker, 1856; Paraproctis Bethune-Baker, 1911; Polymona Walker, 1855; Tamsita Kiriakoff, 1954 (Fig. 2).

Figure 2. 

Seven representatives of newly recorded genera of tussock moths in Mozambique. A. Euproctoides ertli (Wichgraf, 1922); B. Heteronygmia dissimilis (Aurivillius, 1910); C. Leucoma ogovensis (Holland, 1893); D. Ogoa simplex Walker, 1856; E. Paraproctis chionopeza Collenette, 1954; F. Polymona rufifemur Walker, 1855; G. Tamsita habrotima (Tams, 1930). Scale bars: 1 cm.

Our study has reviewed the tussock moth fauna hitherto recorded from the wider Maputaland-Pondoland-Albany and analysed the faunal diversity between those four southern African countries abutting the area of the hotspot. We also have presented a first summary of the tussock moths occurring in Mozambique along with seven genera newly recorded in the country. All these were expected to occur in Mozambique because of their presence in neighbouring countries and these records connect their disjunctive distribution ranges with South Africa. The only exception is the genus Tamsita Kiriakoff, 1954, the presence of which in Mozambique represents the southernmost occurrence of the genus.

The diversity of the tussock moths in Maputaland-Pondoland-Albany displayed several peculiar distributional trends. In spite of the large amount of faunistic studies published about the South African fauna and flora, only very few of them discussed their distributional or biogeographic patterns with regards to the studied countries. We found that the fauna of Lesotho is deeply nested in the South African fauna, but otherwise it has a high turnover among all other countries. This result outlined the potential origin scenario. Lesotho is a country with the high average altitude and the occurrence of specific alti-montane ecoregions (e.g., Drakensberg grasslands and woodlands) with difficult accessibility and hard conditions. Therefore, it was colonized by tussock moth species from neighbouring countries (Sayre et al. 2013). On the other hand, the South African fauna can be considered very similar to the fauna of Mozambique based on the values of nestedness, and simultaneously does not exhibit any faunal exchange towards Eswatini and Lesotho. Thus it forms a gradient of almost the same fauna along the Indian Ocean coast. Our results also highlighted that approximately 27.8% of the South African fauna and 9.6% of the species of Mozambique are potentially endemic to the Maputaland-Pondoland-Albany.

In conclusion, we reviewed and extended the current knowledge of the diversity and distribution patterns of tussock moths in southern Africa. What is more, we also provided a pilot snapshot of species endemicity of Lymantriinae in this region, which contributes to future conservation efforts of this remarkable biodiversity hotspot.

We are greatly indebted to Gyula M. László (The African Natural History Research Trust, United Kingdom) for his help with photographing of specimens and draft reading. We would also like to thank Richard Smith (The African Natural History Research Trust, United Kingdom), Alberto Zilli, Geoff Martin (Natural History Museum London, United Kingdom), Thomas Witt (†) (Museum Witt/Witt Foundation, Germany), Axel Hausmann (Bavarian State Collection of Zoology, Germany) and Rob de Vos (Naturalis Biodiversity Centre, Netherlands) for providing us access to the collections under their care. Work of MR was supported by grant GA JU 038/2019/P provided by the University of South Bohemia.