Taxonomy of the Muscidae (Diptera) of Namibia: A Key to Genera, Diagnoses, New Records and Description of a New Species

ABSTRACT The Muscidae (Diptera) of Namibia were previously known to comprise 42 species in 16 genera. The study of material from the Namibia National Insect Collection, National Museum of Namibia and the Albany Museum (South Africa) loaned to the authors enabled this paper to be written, in which three new generic records and 14 new species records are provided and one new species is described. With the present contribution, the muscid fauna of Namibia is now known to comprise 57 species in 19 genera, with Musca L. being the most species-rich genus. A key to the identification of all recorded genera is provided and diagnoses of the genera and species found in the material studied are provided when pertinent. Musca fragilis sp. n. is described from the Khorixas District.


INTRODUCTION
The muscid fauna of the Afrotropical Region was last catalogued by . More recent contributions include those by Deeming (1987) and Dike (1989Dike ( , 1990 for Afrotropical Atherigona Rondani, and Couri et al. (2006), with a partial revision of the muscid fauna of Madagascar.
Forty-two muscid species in 16 genera are recorded from Namibia in the published a-Atherigona falcata (Thomson, 1869); Musca lasiophthalma Thomson, 1869;M. transvaalensis Zielke, 1971; Lispe barbipes Stein, 1908;and Spilogona aristalis Zielke, 1971-as individual countries were only cited in the Afrotropical Catalogue if distribution was limited. The other records from Namibia are covered in the catalogue collectively as "Eastern to southern Africa", "Congo Basin to South Africa", etc.
This study is based on material loaned from the Namibian National Insect Collection, National Museum of Namibia (Windhoek, Namibia) and the Albany Museum (Grahamstown, South Africa). As a result of the study the number of recorded species is raised of genera, diagnoses of genera and species when pertinent and the description of one new species.

MATERIAL AND METHODS
This review is largely based on material from Namibia deposited in the National Museum of Namibia, Windoek, Namibia (NMNW) and the Albany Museum, Grahamstown, South Africa (AMGS), kindly loaned at different periods to MSC and CJBC by Ashley H. Kirk-Spriggs (now National Museum, Bloemfontein, South Africa). Some specimens are deposited in the Museu Nacional, Universidade Federal do Rio de Janeiro (MNRJ) and Pe. Jesus Santiago Moure Entomological Collection in Curitiba, Paraná, Brazil (DZUP).
Dissected terminalia have been placed in glycerine in microvials pinned beneath the respective specimens.
Terminology follows McAlpine (1981), and for the special characters of Atherigona, such as the trifoliate process, Pont (1986) and Pont & Magpayo (1995). "Postpedicel" Data on the distributions of the species are mainly taken from the Afrotropical catalogue . Genera, and species within genera, are listed alphabetically. Comments on genera or species are added when pertinent. Material examined sections are arranged alphabetically by region.  Fifteeen species of Muscidae are added to the 42 species previously recorded from Namibia, including one new species. The Namibian muscid fauna is now known to contain 57 species and subspecies assigned to 19 genera (Appendix).
Genus Atherigona Rondani, 1856 Atherigona (see Couri et al. 2006, for diagnosis) contains 126 species in the Afrotropical Region, 14 in the subgenus Acritochaeta Grimshaw, 1901 and 112 in the subgenus Atherigona s.str. . Deeming (1971Deeming ( , 1979) studied the species from Nigeria of the Afrotropical species and described new species from Africa. One year later (Dike 1990) described two new species from Nigeria and presented a key for the Afrotropical species of the subgenus Acritochaeta. More recently, Couri et al. (2006) described three new species of the subgenus Atherigona and presented two new records, one of each subgenus from Madagascar.
Among the studied material, only one species was found, A. mitrata, which represents a new record for Namibia.
Atherigona mitrata Séguy, 1955 Diagnosis: Frons strongly projecting; markedly yellow; palpus pale yellow; pedicel yellow, postpedicel grey pollinose, scutum grey; postpronotum and legs yellow, except fore femur brown on apical third of dorsal and anterior surfaces, fore tibia and tarsus light brown. Coenosia is the largest muscid genus occurring in the Afrotropical Region, with 110 described species . Couri et al. (2006) recently described a new species from Madagascar and Pont (2009) described a new species from the Seychelles. See Couri et al. (2006) for generic diagnosis. Coenosia strigipes Stein, 1916 is the only species recorded from Namibia (Emden 1958: 7, "S. W. Africa"). This species was found in the material examined.
Genus Graphomya Robineau-Desvoidy, 1830 Thirteen species of Graphomya have been recorded from the Afrotropical Region. See Couri et al. (2006) for generic diagnosis. The genus and the species G. maculata (Scopoli, 1763) represent new records for Namibia.
Graphomya maculata (Scopoli, 1763) Diagnosis: With characteristic pattern on scutum different in each sex. Male scutum dark brown, including median area, with 2 silvery white vittae along dorsocentral rows of setae and 2 silvery white lateral vittae; scutellum with median triangular brown macula, wider at base, with grey pollinose areas laterally; abdomen predomenantly yellow, with brown median marks and brown tergite 5. Female scutum with silver areas more teral marks.
Genus Haematobia Le Peletier & Serville, 1828 Represented by six species in the Afrotropical Region. The genus and one species are fauna. Diagnosis: General colouration dark greyish, with yellowish tinge; head 1.25× as wide as high; arista plumose only on dorsal surface; palpus spatulate, slightly narrowed in proepisternal depression and postalar wall bare; prealar seta differentiated or vestigial; lower calypter ca 2× as long as upper calypter.

Haematobia
(Roubaud, 1906) Diagnosis: Overall length 2-3.5 mm; prosternum bare; anal vein short, ending abruptly about half distance to wing margin; palpus club-shaped; fore tibia without submedian ventral seta. Genus Haematobosca Bezzi, 1907 Eleven species of Haematobosca are recorded from the Afrotropical Region. A key to world species was provided by Pont & Dsouli (2009). The genus and one species are Diagnosis: General coloration dark; palpus long, as long as proboscis, grooved internally and dilated apically; arista with setulae on dorsal and ventral surfaces.

Musca crassirostris
Musca-type. Wing veins bare. Fore femur with complete rows of posterodorsal and posteroventral setae; fore tibia without posterior median seta. Mid femur with 1 anterior median seta; 1 ventral seta in basal third and 2 subapical posterior setae; mid tibia with 2 posterior setae on mid third and one strong apical ventral seta. Hind femur with complete rows of setae on anterodorsal and anteroventral surfaces, the setae on anteroventral row are stronger on apical half than on basal half; hind tibia with long dorsal preapical seta.
Abdomen and on discal row of tergite 5.