Pseudogaurax cingulatus Sabrosky, 1966

Riccardi, Paula Raile & Pádua, Diego Galvão de, 2021, First record of egg sac predation of the fly Pseudogaurax cingulatus Sabrosky (Diptera, Chloropidae) upon spider Tetragnatha sp. (Araneae, Tetragnathidae) in northern Brazil, Papéis Avulsos de Zoologia 61, pp. 1-5 : 3-4

Pseudogaurax cingulatus Sabrosky, 1966 ( Figs. 6-10 )

Pseudogaurax cingulatus Sabrosky, 1966: 124 .Type locality: Brazil, Rio Grande do Sul, SÃo Leopoldo. Holotype male at Smithsonian Institution National Museum of Natural History ,Washington DC, United States.

Diagnosis: Body pilosity pale. Head entirely yellow except the ocellar tubercle. Scutum yellow with a longitudinal black stripe; anepisternum with a black rounded spot ( Fig. 6 ); scutellum slightly elongate; fore tibia and fore tarsus dark; hind tibia with a blackish stripe on the anterior ⅔; tibial organ concolorous, oval, occupying half of the hind tibia length. Female terminalia telescopic; general shape and pilosity typical of Oscinellinae ; 8 th ab- dominal sternite divided in two lobes ( Fig. 9 ); epiproct black with a pair of setae ( Fig. 8 ); hypoproct pilose with microtrichiae mesally ( Fig. 9 ); cercus narrow with the apex acute. Puparium typical of Chloropidae ; anterior spiracle with four small lobes ( Fig. 10 ).

Remarks: The specimens from Fazenda Agrolucas differ from the type material only in the scutum longitudinal stripe. Sabrosky’s (1966) illustration of P. cingulatus (Fig. 14, p. 123) shows a scutal longitudinal stripe thin anteriorly and slightly wider posteriorly. However, the specimen from Fazenda Agrolucas exhibits an anchor-like mark posteriorly ( Fig. 7 ) which is considered here an intraspecific variation. On the other hand, the additional specimens examined from Ilha de Maracá have the scutal stripe as the type of P. cingulatus , but the dark marks on the legs are faded. Pseudogaurax nigrolineatus (Enderlein) is another Brazilian species which has a scutum similar to P. cingulatus , but the absence of dark spots on pleuron and legs completely yellow are features restricted to the former species ( Sabrosky, 1966). Unfortunately, no information on the male terminalia of P. cingulatus is available. This organ could improve the species identification and help confirm the specimens identity.

Material examined: 4 ♀♀ from BRAZIL, Roraima, Fazenda Agrolucas, 02°52′29.7″N, 60°51′48.9″W, egg sacs collected 22.viii.2019 and specimen emerged on 04.ix.2019, N. Hamada leg. [ MZUSP and INPA]. 2 ♀♀ from BRAZIL, Roraima, Ilha de Maracá, EstaÇÃo Ecológica de Maracá , 03°22.623′N, 61°26.136′W, 101 m, Malaise trap ponto 5, trilha Santa Rosa, 20.xi-05.xii.2015, Biffi, Falaschi, Marinho & Riccardi leg. [ MZUSP] ; 1 ♀ same data except 29.ix-14.x.2015 [ MZUSP] .

Biological note: Egg sac predator of the spider Metazygia unguiformis (= Alpaida veniliae (Keyserling)) (Araneidae) ( Sabrosky, 1966) and Tetragnatha sp. (Tetragnathidae) ( Figs. 1-4 ).

Distribution: Brazil (Roraima, SÃo Paulo, Rio Grande do Sul) ( Fig. 1 ).

Figures

Figure 1. Geographic distribution of Pseudogaurax cingulatus Sabrosky (Diptera,Chloropidae) in Brazil.

Figures 2-5. Tetragnatha sp.(Araneae,Tetragnathidae) (female).(2) adult face,frontal view. (3) adult habitus,dorsal view.(4) adult habitus,ventral view.(5) egg sac,rectangle enlargingand showing opening and apex of the puparium from which oneof the flies emerged.

Figures6-10.PseudogauraxcingulatusSabrosky (Diptera,Chloropidae)(female).(6)adulthabitus(scalebar =0.5mm).(7) adult,dorsalview.(8) femaleterminalia in dorsal view (scale bar = 0.1 mm). (9) female terminalia inventral view (scale bar = 0.1 mm). (10) puparium in dorsal view;anterior left side (scale bar = 1 mm). Abbreviations:cer,cercus;epi,epiproct;hypo,hypoproct;st8, 8th abdominal sternite.