
588 RECORDS OF THE S.A. MUSEUM 
darker brown; humeral region of praescutum restrictedly yellow; each scutal 
lobe with two grey areas, the remainder dark brown; seutellum brownish grey, 
with a central brown line; mediotergite buffy grey; the narrow posterior border 
and a capillary median line darker. Pleura with the dorsopleural region buffy 
yellow, below which is a brown longitudinal stripe extending from the cervical 
region backward, becoming obsolete at the pteropleurite; ventral pleurites grey 
(type) or more yellowed (allotype), the sternopleurite patterned with darker, 
especially in the type. Tlalteres dark brown, the base of stem narrowly yellow. Legs 
with the coxae yellowish grey, patterned with brown, very distinetly so in the type, 
nearly obsolete in the alloty;pe: femora yellow, the tips broadly blackened ; tibiae 
and tarsi yellow, the latter darker at tips. Wings relatively narrow, the ground 
colour brownish yellow, restrictedly patterned with darker, ineluding cells @ and 
Se and the outer radial field in cells Seo, Ry and Rg; stigma and a conspicuous 
seam over m—ci and distal section of vein Cu darker brown; obliterative streak 
on auterior cord restricted in area; veins brown, more yellowed in the obliterative 
field, Venation: Cell Ry strongly constricted before midlength, at the narrowest 
point a little more than one-third as wide as it is across the sibbasal portion; 
m—cv at near one-third the length of Mg 44. 
Abdominal tergites dark veddish brown, with indications of still darker 
brown median and sublateral stripes, the lateral borders narrowly dark brown; 
sternites dark brownish grey. 
Holotype, @, Torricelli Mountains, altitude 200-1,000 feet, January, 1939 
(Cheesman). Allotopotype, a broken 2, 
Superficially the present fly is most like Ctenacroscelis umbrinus 
(Wiedeman), differing ecouspicuously in the structure of the antennae, details of 
colovation, and the unusually constricted eell Ry of the wings. 
CTENACROSCELIS ILLEX sp. Nov, 
Size large (wing, male, 36 mm.) ; mesonotal praescutum with three dark 
grey stripes that are bordered by brown; pleura yellow, variegated by brown 
areas; femora brownish yellow, the tips dark brown, preceded by a clearer yellow 
ring; wings Jong and narrow, restrictedly patterned with brown; male 
hypopygium with the tergal lobes short, ucarly trumeste, the median area with 
a broad furrow ; inner dististyle long and slender, the outer half a long blade that 
terminates in a deeurved beak, 
é@ Length, about 28 mm.; wing, 36 mw.; antenna, about 3-9 mm, 
Frontal prolongation of head a little shorter than the remainder, light brown; 
nusus elongate; basal three palpal segments brown, paler at the ineisures, the 
terminal segment dark brown. Antennae with the flagellar segments almost. 
cylindrical, not or scarcely produced. Head above dark fulyous brown, still 
