FRUIT FLIES OF THE RYUKYU ISLAXaS 



19 



reaching the oral margin, externo-inferior margins of 

 antennal fossae black; orbits narrow but distinct, 

 lightly covered witli a greyish tomentum, in profile 

 slightly hollowed alxmt tlie middle and conspicuously 

 produced toward the upper mouth-edge. Back of head 

 (pi. 7, fig. 2) moderately convex, light waxy yellow, 

 largely somewhat brownisli around occipital foramen; 

 cheeks short and narrow, with rather shallow genal 

 groove, sometimes with an inconspicuous brown sjjot 

 just below lower angle of eye. All bristles black, ratlier 

 strong, the ocellars and postverticals very weak; 

 lower inferior fronto-orbital bristles composed of two 

 or rarely tlnee bristles, placed closely; genal weak, 

 aljt)ut as long as the postvertical. Antennae (pi. 7, 

 fig. 8) moderate in length, light reddish yellow, with 

 two basal segments paler; first segment as long as wide; 

 just behind upper apical margin almost always a small 

 ill-defined blackish dot with seven or more black short 

 bristles along dorso-apiciil marghi; second segment 

 longer than 1/3 the third one, somewhat blackish 

 toward the dorso-external apex, with a strong black 

 median bristle which is a little longer than the segment, 

 the remaining apical marginal bristles yellowish and 

 rather weak; third segment nearly four times as long 

 as wide, very sliglitly narrowed toward the evenly 

 rounded apex, witli a blackish, bare arista which has a 

 rather long yellow basal segment. Palpi (i)l. 7, fig. 9) 

 comparatively large, about 2.5 times as long as wide, 

 basal thiixl narrowed and moderately bent, apex evenly 

 slightly rounded. 



Thorax rounded, luirrowed toward the straight 

 anterior margin. Mesonotum (pi. 7, fig. 5) black, with 

 the wing-bases brownish, the humeral, notopleural, 

 very small presutural, lateral postsutural, and com- 

 paratively narrow median postsutm-al calli, liglit yellow; 

 surface obscured by a greyish tomentum and a light 

 yellow pubescence, with the exception of three narrow 

 nontomentose longitudinal stripes, of which the median 

 one is finer and hardly extends to the streaks bordering 

 the median yellow postsutural callus, the latter being 

 usually narrower than the lateral calli and not reaching 

 the posterior margin of the disk; the submedian lateral 

 nontomentose stripes hiterrupted at the suture and 

 distinctly widened toward the inner margins of luuneral 

 calli, but when seen from the side they are of nearly 

 the same width throughout their length; yellow lateral 

 postsutural stripes hardly attaining the scutellum, 

 nontomentose along both sides; humeral calli rather 

 large, about twice as long as wide or longer than half 

 the anterior margin of the disk as seen from above; 

 nontopleural calli small but conspicuously elevated; 

 presutural calli very small and narrow. ScutcUum 



evenly rounded apically, light yellow, with a rather 

 large black apical spot. Pleura (pi. 7, fig. 6) black, the 

 anterior ])ortion usually reddisli brown or sometimes 

 yellowish brown, often brownish black or- rarely yel- 

 lowisli brown behind the yellow mesopleural spot, 

 reddisli Ijrown above the midleg; yellowisli sternopleural 

 spot almost always small but distinct, while the yellow 

 metajjleural s|)ot is large; mesophragma black or 

 brownish black. All bristles black, nu)derate in length, 

 tlie humeral very fine and outer scapular sometimes 

 wanting; pteroi)leural distinct, but sternopleural 

 wanting; two pah's scutellars, the apical somewhat 

 stronger than tlie basal aiul ahmisl always slightly 

 directed inward. 



Abdomen (pi. 7, fig. 7) yellow lo orange yellow, 

 obscured by whitish pubescence; first tergum blackish 

 at the anterior and lateral borders, often with an ill- 

 defined blackish triangular spot on the middle, or 

 sometimes entirely black; the lateral hairs moderately 

 long and more or less brownish; second to fifth terga 

 each with a black basal band, the first not reaching to 

 the lateral margins and sometimes luuTowed or 

 broadened about the middle, the second produced into a 

 short triangular median projection, the third with a 

 similar but narrower and longer median poslerioi- 

 projection not reaching the hind nuirgin, often inter- 

 rupted in tlie midtUe, usually very broad; fifth tergum 

 with a narrow black median longitudinal streak hardly 

 extendhig to the posterior margin, the shming patches 

 reddish brown to brownish black, rather large, traverse 

 oblong; the bristles of the tliird tergum black, moderate 

 in length. Sterna almost all sinning black, often the 

 middle one or two reddish brown ; the lateral membranes 

 orange yellow; genitalia almost alw ays blackish to black. 



Wing (pi. 7, fig. 1) rather broad with tlie large super- 

 numerary lobe in which there arc a few black shaggy 

 hairs; B.^^-, very slightly undulate at the apical half, 

 distinctly bristled from the base to near the apex, 

 sometimes two rows of bristles near the middle; r-Tu 

 straigiit or sometimes slightly bent near posterior end; 

 prolongation of anal cell comparatively short, nearly 

 as long as cell proper; pterostigma and R, brown to 

 blackish brown, this color extending to l)efore I he middle 

 of the mouth of R,, along the wing margin and moder- 

 ately widened hi R3 and R5, so that tlie ratlier narrow 

 costal band has a small apical spot; m-cu very slightly 

 sinuate, bordered with a brown tint, this color being 

 conspicuously widened posteriorly and narrowed ante- 

 riorly and often interrupted before the middle; anal 

 stripe brown to blackish brown, rather broad, somewhat 

 paler at each end; anal lobe rather broad and short. 

 Halteres rather small, light yellow . 



