Jason G.H. LONDT

Natal Museum, Private Bag 9070, Pietermaritzburg, 3200 South Africa, and School of Botany and Zoology, University of KwaZulu-Natal, Pietermaritzburg

A REVIEW OF THE AFROTROPICAL SPECIES OF NUSA WALKER, 1851(DIPTERA: : LAPHRIINAE)

Londt, J.G.H., 2006. A review of the afrotropical species of Nusa Walker, 1851 (Diptera: Asilidae: Laphriinae). – Tijdschrift voor Entomologie 149: 101-120, figs. 1-32, tables 1-5. [issn 0040-7496]. Published 1 June 2006. Afrotropical species of Nusa Walker, 1851 are reviewed. Three species are recognised, including the widespread N. infumata (Loew, 1851), which is a highly variable species displaying some sexual dimorphism, geographical variation, and melanism over much of its wide range. An analysis of the observed variation is attempted, but no explanation found. The other two spe- cies, N. ingwavuma Oldroyd, 1974 and N. eos sp. n. have far more restricted distributions; are largely confined to the eastern fringe of Africa and can be readily separated from N. infumata. These two species are morphologically very similar to one another, and can only be separated on differences in male genitalia. A key to the species and a discussion of the genus are provided. New species: N. eos recorded from Ethiopia, Kenya (type locality Garissa), Somalia, Sudan and Tanzania. New synonymy: N. infumata = Dasythrix dispar Gerstaecker, 1871; Dasythrix vittipes Bezzi, 1915; Nusa gaerdesi Lindner, 1973. Jason G.H. Londt, Natal Museum, Private Bag 9070, Pietermaritzburg, 3200 South Africa, E-mail: [email protected] School of Botany and Zoology, University of KwaZulu-Natal, Pietermaritzburg Key words. – Afrotropical, Asilidae, Nusa, variation, distribution, new species, new synonymy.

A survey of catalogues (including Oldroyd 1975, Walker 1851 (June) – Described Nusa to accom- Oldroyd 1980 and Lehr 1988) and subsequent pub- modate two new Indian species (aequalis and formio), lications indicates that some 31 species names are but neglected to designate a type species. currently available within the genus Nusa Walker, Loew 1851 (September) – Described Dasythrix as 1851. A list (Table 1) of these names in order of a subgenus of , dividing it into two poorly di- their description, and including names believed to agnosed ‘groups’. Group one accommodated a South be synonymous, shows that the majority of species American species (inornata) and was characterised by are oriental (21), while others are afrotropical (7) having the postpedicel ‘gestreckt und ziemlich schmal, or palaearctic (3). Two species (Laphria (Dasythrix) etwas länger als die beiden ersten Glieder zusammen’. inornata Loew, 1851 and Dasythrix leucophaea Lynch Group two accommodated two new African species, Arribalzaga, 1880), which had been tentatively listed infumata and brachyptera, from ‘Cap’ (Cape of Good as species of Nusa in the neotropical catalogue of Hope) described as having the postpedicel ‘viel kürzer Martin & Papavero (1970), were subsequently as- und breiter’. He clearly stated that ‘dieser Fühlerbau signed to Dasythrix Loew, 1851 by Artigas, Papavero unterscheidet die Arten der 1sten Gruppe von denen & Pimentel (1988), and are excluded from the list. der 2ten’. However, as the placement of these species may still Loew 1858 – Described Dasythrix stenura be in doubt, they are discussed again later in this from ‘Caffraria’, observing that it was a variety of paper. infumata. The afrotropical Nusa fauna, although small, has a Loew 1860 – Repeated his description of Dasythrix long history, complicated by the assignment of some stenura, from ‘Caffrerei und Nolagi’. He listed species to Dasythrix Loew, 1951, but it can be briefly infumata and brachyptera, providing comparative summarised as follows: notes.

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Table 1. A chronological list of species names applied in Engel 1928 – Provided an account of Dasythrix, Nusa Walker, 1951. Previously listed synonyms are indi- cated. Abbreviations – A = Afrotropical, N = Neotropical, stating that infumata Loew was the ‘genotype’. O = Oriental, P = Palaearctic. Engel 1932 – Described Dasythrix albicans from Sawmills, Zimbabwe, without commenting on elva (Walker, 1849) (Asilus) O Hermann’s (1912) actions. aequalis Walker, 1851 O Hull 1962 – Redescribed Nusa as part of his study formio Walker, 1851 O of world genera, giving Dasythrix as a synonym and infumata (Loew, 1851) (Laphria) A brachyptera (Loew, 1851) (Laphria) A = infumata providing excellent illustrations. He listed all known stenura (Loew, 1858) (Dasythrix) A = infumata species in the world fauna, including the following dispar (Gerstaecker, 1871) (Dasythrix) A afrotropical taxa: africana, albicans, brachyptera (with ramicosa (Loew, 1871) (Dasythrix) P stenura as a synonym), dispar, infumata, ?nigrapex, puella (Rondani, 1873) (Halictosoma) P ruficornis, and vittipes. grisea (Hermann, 1914) (Dasythrix) O Oldroyd 1970 – In reviewing the asilids of the trianguligera (Austen, 1914) (Dasythrix) P vittipes (Bezzi, 1915) (Dasythrix) A then Belgium Congo (now the Democratic Repub- albibasis Ricardo, 1927 O lic of Congo), he included Nusa in a key to African yerburyi Ricardo, 1927 O Laphriini (with Dasythrix and Halictosoma Rondani, gaerdesi Lindner, 1973 A 1873 listed as synonyms), even though no representa- ingwavuma Oldroyd, 1974 A tives of the genus were recorded from the country. He bengalensis Joseph & Parui, 1987 O provided a useful discussion (p. 243-4) of some of the ghorpadei Joseph & Parui, 1987 O indica Joseph & Parui, 1987 O confusion surrounding the genus, and observed that pseudoalbibasis Joseph & Parui, 1987 O the Nusa type species (aequalis) was congeneric with karikalensis Joseph & Parui, 1989 O the African species and that Loew’s South American bhargavai Joseph & Parui, 1992 O species (inornata) would be the type species of any rajasthanensis Joseph & Parui, 1992 O restricted Dasythrix. Oldroyd had studied Ricar- setosa Joseph & Parui, 1992 O do’s africana material, and transferred the species to shevaroyensis Joseph & Parui, 1992 O geniculata Joseph & Parui, 1997 O Proagonistes Loew, 1858. mukherjeei Joseph & Parui, 1997 O Lindner 1973 – Described Nusa gaerdesi from sahai Joseph & Parui, 1997 O Namibia. sirkari Joseph & Parui, 1997 O Oldroyd 1974 – In reviewing the southern andhraensis Joseph & Parui, 1999 O African asilid fauna, Oldroyd briefly mentioned the balraji Joseph & Parui, 1999 O complications surrounding Nusa and referred to his earlier (1970) comments. In addition, he transferred albicans to a new genus, Laphystotes, listed nigrapex as a synonym of flavipes Wiedemann, 1821, Gerstaecker 1871 – Described Dasythrix dispar and described Nusa ingwavuma from KwaZulu- from Zanzibar (Tanzania). Natal, providing a key to separate it from the only Bigot 1878 – Described Dasythrix nigrapex from other southern African species (infumata). South Africa. Oldroyd 1980 – Catalogued the afrotropical Wulp 1899 – Described Dasythrix ruficornis from species, including dispar, gaerdesi, infumata (with South Yemen (Yemen). brachyptera and stenura as synonyms), ingwavuma and Hermann 1912 – Designated aequalis as type spe- vittipes. Dasythrix ruficornis was catalogued in Ctenota cies of Nusa, an action that had the consequence of Loew, 1873. effectively accommodating oriental and afrotropical Londt 1988 – Included Nusa in an updated key to Dasythrix species in Nusa. The position of neotropical afrotropical laphriine genera. Dasythrix species, however, remained unresolved. Bezzi 1915 – Apparently unaware of Hermann’s At the commencement of this study there were work, described Dasythrix vittipes from Somalia. five valid species of afrotropical Nusa, i.e. those cata- Ricardo 1925 – Described Nusa africana from logued by Oldroyd (1980). The issue relating to the Malawi based on material identified by Hermann. validity of Dasythrix and the correct placement of As Hermann believed Nusa to be an earlier name for South American species had seemingly been resolved Rondani, 1856, Ricardo suggested that by Artigas et al. (1988), who, without reference to the the species may be congeneric with Andrenosoma confused history of the name, placed Dasythrix Loew, boranica Corti, 1895 from East Africa. 1851 in a new tribe (Dasytrichini) without provid- Ricardo 1927 – Discussed Nusa, confirming ing an adequate diagnosis or a list of the species in- its precedence over Dasythrix, and transferred her volved. Although Sabrosky (1999) and Dikow (2003) africana to Andrenosoma. in reviewing the family-group names in Asilidae listed

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