Scathophaga merdaria (FABRICIUS, 1794)

Šifner, František, 2020, Scathophaga karmazini nov. sp., a new species from Austria, with a key to Scathophaga species from Central Europe (Diptera, Scathophagidae), Linzer biologische Beiträge 52 (1), pp. 731-757 : 735-736

Scathophaga merdaria (FABRICIUS, 1794) ( Figs 37–40 )

M a t e r i a l e x a m i n e d: CZECH REPUBLIC: Chyňava , 6.xi.2002, 1♂, 30.xi.2002, 5♀♀, Šifner leg. ; Šumava Mts. , Smrčina Mt., 5.iv.‒4.v.2007, 4♂♂, Liška leg. ( FSPC) .

D i a g n o s i s. Male. The submedial processes of sternite 5 wide, lateral parts of sternite elongate, narrow, and long haired, sternite 4 wide but distally weakly narrowed, sternite 3 rectangular wide, of equal size as sternite 4 ( Fig. 37 ), surstyli wide basally, arched and pointed apically, cerci densely haired ( Fig. 38 ), pregonite narrow, with one seta laterally and one seta apically ( Fig. 39 ).

Female. The abdominal sternite 7 divided into three separate sclerites which vary in shape, all connected by hyaline membrane, sclerite 6 and 5 more or less quadrate, with distinct bristles ( Figs 40 a, b, c, d ).

C o m m e n t s. This species and its nearest relative, S. stercoraria (LINNAEUS, 1758) , were mentioned by MEIGEN (1826) as two separate species based especially on the colour characters. SCHINER (1864) also regarded both species as separate species. BECKER (1894) suggested the number and position of the acrostichal bristles as a distinguishing character. SZILADY (1926, 1943) and STACKELBERG (1933) present two rows of the acrostichal bristles in S. merdaria and more rows of these in S. stercoraria as their basic distinguishing character. The other authors, for exemple SACK (1937), SÉGUY (1952) and GORODKOV (1986) interpreted S. merdaria as a synonym or a variety of S. stercoraria ; an analogical approach was adopted by ŠIFNER (2008). Nowadays, in my opinion, S. merdaria and S. stercoraria are two separate species, which is I confirm by the study of a considerable number of specimens for the comparison. The basic differences between these species are apparent from the text and the figures (cf. Figs 37– 40 : S. merdaria and Figs 49–62 : S. stercoraria ) and they are also applied in the key.

D i s t r i b u t i o n. Probably in all Central European countries, so far confirmed from Czech Republic on following localities: Jizerka (5158) ; Horní Maxov (5257) ; Krkonoše Mts., Labská bouda (5259) ; Poniklá (5338) ; Žacléř (5361) ; Boží Dar (5543) ; Vintířov (5742) ; Řevničov (5848) ; Lazy, Lesný (5941) ; Kladská, Bečov (5942) ; Horní Bezděkov, Chyňava (5950) ; Praha, Šeberovský rybník pond (5952) ; Vysoká, Tachovská Huť , Tři Sekery (6041) ; Mamerníky, Mariánské Lázně (6042) ; Skryje (6048) ; Broumov (6141) ( FSPC) .

Scathophaga moraviensis ŠIFNER, 2011 ( Figs 41–44 ) M a t e r i a l e x a m i n e d: CZECH REPUBLIC: Hrubá Vrbka (7170), Čertoryje, Malaise trap, 25.v.2010, 1♂, 1♀ (holotype, allotype), Chvojka leg. (FSPC).

D i a g n o s i s. Male. The abdominal sternite 5 more or less semi-circular, the submedial processes weakly developed, sternite 4 wide, narrowed distally, sternite 3 rectangular ( Fig. 41 ), surstyli almost straight, only weakly arched and pointed, cerci in upper part long haired ( Fig. 42 ), pregonite wide with one long seta and one short seta apically ( Fig. 43 ).

Female. The abdominal sternite 7 wide with a caudal incision, sternite 6 with a promotory distally and always one bristle laterally, sternite 5 oval with two bristles latero-caudally ( Fig. 44 ).

C o m m e n t s. This species was described from Moravia (eastern part of the Czech Republic) and nowadays, it was discovered in further on localities in Bohemia and Moravia: Chyňava (5950), Šumava Mts. Jezerní Mt. (6845), Řevničov (5848) (ŠIFNER, in litt.). D i s t r i b u t i o n. Known only in Czech Republic ( ŠIFNER 2011).

Figures

Figs 37-40. Scathophaga merdaria (FABRICIUS, 1794). (37) male abdominal sternite 5 to 3; (38) cerci and surstyli (caudal view); (39) left pregonite; (40a,b,c,d) the shape of the female abdominal sternites 7 to 5; Scale bars: 0.5 mm (Figs 37, 38, 40a,b,c,d); 0.1 mm (Fig. 39).

Figs 49-52. Scathophaga stercoraria (LINNAEUS, 1758). (49) male abdominal sternites 5 to 3; (50) cerci and surstyli (caudal view); (51) right pregonite; (52a,b,c,d) the shape of female abdominal sternites 7 to 5. Scale bars: 0.5 mm (Figs 49, 50, 52a,b,c,d); 0.1 mm (Fig. 51).

Figs 53-56. Scathophaga suilla (FABRICIUS, 1794). (53) male abdominal sternites 5 to 3; (54) cerci and surstyli (caudal view); (55) right pregonite; (56) female abdominal sternites 8 to 5. Scale bars: 0.5 mm (Figs 53, 54, 56); 0.1 mm (Fig. 55).

Figs 57-60. Scathophaga taeniopa (RONDANI 1867). (57) male abdominal sternites 5 to 2; (58) cerci and surstyli (caudal view); (59) right pregonite; (60) female abdominal sternites 8 to 5. Scale bars: 0.5 mm (Figs 57, 58, 60); 0.1 mm (fig. 59).

Figs 61-63. Scathophaga vlastae ŠIFNER, 2000. (61) male abdominal sternites 5 to 4; (62) cerci and surstyli (caudal view); (63) right pregonite. Scale bars: 0.5 mm (Fig. 61, 62); 0.1 mm (Fig. 63).

Figs 41-44. Scathophaga moraviensis ŠIFNER, 2011. (41) male abdominal stzernites 5 to 2; (42) cerci and surstyli (caudal view); (43) right pregonite; (44) female abdominal sternites 8 to 5; Scale bars: 0.5 mm (Figs 41, 42, 44); 0.1 mm (Fig. 43).