FRUIT FLIES OF THE RYUKYU ISLANDS 



85 



as the four basal tarsal segments together, with a black 

 apical spur and very short black bristles at apex; 

 first tarsal segment nearly as long as the three follow- 

 ing segments together, externoventral margin with 

 black short bristles, mternoventral surface yellowish 

 with brushlike bristles. Hindleg (pi. 31, fig. 13) 

 strongest: femur conspicuously longer than tibia, 

 distinctly narrowed toward each end, one pair of 

 blackish bristly hairs near dorsal apex; tibia as 

 long as tiie three basal tarsal segments together; 

 first tarsal segment slightly longer than the three 

 following segments together, yellowish brushlike 

 bristles on internoventral surface rather long, externo- 

 ventral margin with blackish bristly hairs. 



Length: Body 1.8-3.2 mm., wing 2-3.4 mm. 



Fem.\le. — Quite sunilar to male. Sixth abdominal 

 tergum (pi. 31, fig. 10) slightly longer than preceding, 

 with four or five pau's of marginal bristles; ovipositor 

 long and depressed, first segment distinctly longer 

 than fifth and sixth terga combined, almost always 

 shining castaneous black with apical lialf yellowish 

 brown, rather densely pubescent, second segment 

 fully two-thirds as long as basal, apex widened and 

 with two pairs of tiny black spines, ovi[)osit(>r ])ointed 

 at apex. 



Length: Body (without ovipositor) 2-3 mm., wing 

 2.1-3.2 mm. 



^L\TERI.\L Ex.\MiN'ED. — Irioiiiote Is.: 2c^, 9, Jan. 7- 

 21 : Okinawa Is. : 55 cT, 29 9, Mar. 24-Apr. 20; collected 

 on Erechtites ralerianaefolia Wolf and You ngia japonica L. 



Rem.\rks. — The present material is quite the same 

 as Formosan Ensina lactaepennis Hendel, and there is no 

 difference between it and European E. sonchi L. 



Ensina sororcula (Wiedemann) 



Pl.vte 32 



Trypeta sororcula Wiedemann, 1S30, p. .)09. 



Ensina chilensis Alacqaart, 1843, p. 387, pi. 31, fig. 11. 



Ensina vaciUans Wollaston, 18.58, p. 115. 



Ensina humilis Loew, 1862a, p. 81. 



Leptomyza variipennis van der Wulp, 1897, p. 143, pi. 3, figs. 3, 4. 



Ensina biselosa Endcrlcin, 1911, p. 4r>b, figs. Y, Z. 



Ensina biselosa var. nigrinotum Endcrk'iii, 1911, p. 4.')6. 



Ensina sororcula (Wiedemann). — Shiraki, 1933, p. 462. 



One of the smallest species of all the Ryukyu fruit 

 flies, dark brown, yellow pubescent, the wings brown 

 with whitish subhyaline spots and the abdomen with 

 paired spots. 



M.\LE. — Head slightly narrower than thorax, dis- 

 tinctly narrowed forward, wider tlian liigh, nearly as 

 long as wide. Frons (pi. 32, fig. 3) nearly twice as wide 

 as eye, distinctly narrowed forward, lateral margins 

 straight, flat, orange yellow to light reddish brown, 

 very often darkened on posterior half, between these 



two colorations a rather distinct transverse sulcus; 

 orbits more or le.ss elevated, white tomentose, with 

 very s|)arse whitish pubescence; lunule greyish dusted, 

 more or less swollen, far behind lunule an ill-defined 

 arcuate sulcus; vertical calli narrow and long, nearly 

 two-fifths as long as frons but not distinctly defined, 

 whitish tomentose, very slightly convergent; ocellar 

 triangle comjiaratively small, black or blackish, just 

 behind which is a distinct transverse carina. Face (pi. 

 32, fig. 4) nearly as wide as one eye, nearly as long as 

 wide, slightly broadened below, oral margin strongly 

 produced, light yellowish, whitish tomentose; orbits 

 comparatively broad, moderately widened below, dis- 

 tinctly whitish tomentose; vibrissal margins with 

 minute brownish veiy sparse curved bristles, the 

 upper two or three of which are quite erect and yel- 

 lowish; antennal grooves rather deep and broad, more 

 or less darkened. Back of head (pi. 32, fig. 2) moderately 

 swollen, up])er portion flat, blackish brown or black, 

 eye-margms except median portion, u])i)er corner, and 

 lower border broadly yellowish, entu-ely greyish to- 

 mentose, ventral border with three or four long yel- 

 lowish bristles, posterior border with short yellowish 

 bristly hairs; cheeks comparatively narrow, yellowish, 

 whitish tomentose, genal groove distinct and com- 

 paratively broad, vibrissal margins with short j-ellowish 

 bristly hairs. Eye in profile oval, moderately oblique, 

 upper angle narrowed, in front view inner margiii 

 broadly rounded. Antenna (pi. 32, fig. 9) inserted at 

 middle of eye and close together, short, almost attaining 

 oral margin, yellow to dii-ty orange yellow; second 

 segment nearly half as long as third, very sparsely 

 black |)ubescent along a])ical margin, wilhout distinct 

 median bristle; third segment broad, twice as long as 

 wide, dorsal margin straight, ventral margin slightly 

 convex, a|)ex broadly rounded; arista microscoi)ically 

 pubescent, blackish, basal segments yellowish. l'ali)i 

 (pi. 32, fig. 10) long and slender, distinctly broadened 

 toward base, yellowish, somewhat darkened toward 

 ai)ex, bristles very s|)arse, tlie ajjical one conspicuously 

 long. All bristles black, excej)! upper superior fronto- 

 orbital, postverticals, outer verticals, genal and bristles 

 of occi|)ital row yeflowish white. Ocellars divergent, 

 as long as lower superior fronto-orbitals; fronto- 



rbita 



9-0 



ui>per superiors distinctly shorter than 

 lowers, inferiors directed inward, iiardly crossed, 

 sligiitly finer tlian superiors; postverticals jjarallel, 

 slightlv longer tlian upper superior fronto-orbitals; 

 inner verticals i)arallel, longest, nearly twice as long 

 as lower superior fronto-orbitals, outer verticals nearly 

 as long as latter; two or three whitish and several 

 blackisli bristles in occipital row; occipital bristles 

 wantinu;. 



