182 
PACIFIC SCIENCE, Vol. V, April, 1951 
and is not interrupted in the middle of 
1st M2. The apical portion of the wing is 
hyaline except for a narrow brown to black 
band extending transversely through the 
apical third of the wing and continuing 
around the costal margin to nearly the middle 
of cell R5 and for the narrow black streak 
which extends obliquely from the apex of 
vein Mi +2 to vein R4+5. Vein R4+5 is setulose 
only to the r-m crossvein. Vein R3 is very 
slightly wavy and the ultimate section of 
vein R4+5 is curved upward in the middle 
portion. The third costal section (stigma or 
subcostal cell) is about two-thirds as long 
as the second section. The r-m crossvein is 
situated about its own length from the end 
of the discal cell (1st M2), and the m crossvein 
is vertical in position. The narrowed portion 
of the cubital cell is equal to slightly more 
than half the length of the r-m cross vein. 
Vein Cui-j-lst A extends to the wing margin. 
Abdomen: All black, polished on the fifth 
tergum and subopaque on terga 1 to 4. 
Rather thickly covered with short, black 
reclinate hairs and with six to eight strong 
bristles on the apical margin of the fifth 
tergum. The genitalia have not been studied 
carefully. They are tinged with yellowish and 
the lobes of the ninth segment are slender, 
rather elongate, and bear long hairs at their 
apices. 
Length: Body, 4.2 mm.; wings, 3.8 mm. 
FEMALE. Very similar to the male. Terga 4 
and 5 and the basal segment of the ovipositor 
(segment 7) are polished black. The ovi- 
positor is inconspicuous from a dorsal view — 
just the basal portion is visible. The exposed 
portion of the ovipositor is about equal in 
length to the fifth abdominal segment. The 
extended ovipositor is short and thick (Fig. 
29 b), and the tip of the piercer is character- 
istically tapered. The full length of the ovi- 
positor is about 1.9 mm. The piercer is ap- 
proximately 0.6 mm. long by 0.18 mm. at its 
broadest point. The basal three-fifths of the 
piercer is straight sided. At the point where 
the piercer begins to taper, a tubercle is lo- 
cated on each side; beyond (at the apical two- 
fifths) the piercer tapers abruptly into a sharp 
point (Fig. 29c). The opening of the oviduct 
is about 0.18 mm. from the apex of the 
piercer, and there are no preapical setae pres- 
ent. The inversion membrane is about 0.6 
mm. long by 0.26 mm. wide; the scales of 
the rasper extend to about 0.18 mm. from 
the base of the segment. The remainder of 
this segment is densely covered with scales 
which vary in shape from thorn-like on the 
apical portion, triangular in the middle, and 
obtuse at the basal part of the rasper. The 
basal segment of the ovipositor is about 0.75 
mm. long by 0.9 mm. across its hind margin. 
The spiracles are located about 0.3 mm. from 
the base of the segment. 
Length: Body, 4. 2-4.5 mm.; wings, 3.8- 
4.0 mm. 
Holotype male, allotype female, and 14 
paratypes (10 females and 4 males): Flartley’s 
Creek, N. Queensland, ex Primna nauseosa, 
Feb., 1950. 
Type, allotype, and two paratypes are in 
the United States National Museum. Three 
paratypes are in the Bishop Museum, Hono- 
lulu, T. H.; three in the Board of Agriculture 
and Forestry collection, Honolulu, T. H.; 
two in the Hawaiian Sugar Planters’ Associa- 
tion collection, Honolulu, T. H.; three at the 
University of Hawaii; and one in Dr. M. 
Hering’s collection at the University of Berlin. 
RIOXA Walker 
Rioxa Walker 1857. Linn. Soc. Lond., Proc. 
1: 35. 
The members of this genus are distin- 
guished from other Trypetinae which have 
six scutellar bristles and a plumose arista by 
having veins Ri-1-2 and R4-1-5 setulose but with 
the setulae on R1+2 not extending onto the 
node of the radial vein, by having the wings 
chiefly brown to black with round hyaline 
spots in the middle of the wing and hyaline 
