208 
PACIFIC SCIENCE, VoL XII, July, 1958 
ninth tergum of the male and by having the 
claspers pointed on the outer apices (Fig. 18^) ; 
rather than the lobes of the tergum being 
subacutely pointed, the claspers rather triang- 
ular, and a narrow lobe extending from the 
hind margin of the sternum along the inner 
side of each clasper (Fig. 15 a). 
A small species with rostrum not strongly 
produced and only about three-fourths as long 
as antennae. Antennae brown to black, 9- 
segmented in the male, 11 -segmented in the 
female. Ocellar tubercle large and prominent. 
Mesonotum and scutellum (except for a black 
line down the latter) entirely opaque rufous. 
Pleura brown, tinged with rufous especially 
on sternopleura. Legs black in the male, tinged 
with rufous in the female. Front tibia rather 
strongly swollen, especially in the male, in the 
middle it is equal to slightly wider than the 
thickest part of the femur. Wings light brown 
fumose. Vein R 2+ 3 bent near base, entering 
the costa at about a 65° angle to K4+5. Petiole 
of cell M 2 not much longer than r-m cross 
vein. Cubital cell not at all narrowed at apex. 
Abdomen and genitalia dark brown to black. 
Ninth tergum with a V-shaped cleft in middle 
of hind margin, dividing the segment into 
two nearly quadrate lobes (Fig. 18A). The 
ninth sternum is rather strongly forcipate, the 
lobes on the posterior lateral margins are slen- 
der and sharply pointed. The posterior median 
margin of the sternum has a broad round- 
topped lobe extending approximately as far 
as apices of claspers. The claspers are short 
and broad, broadly rounded on inner apex, 
and with a subacute, densely setulose lobe on 
outer apex (Fig. 18 a). 
Length: Body, 4. 5-5.0 mm.; wings, 5.0- 
6.4 mm. 
type LOCALITY: Mabek, Peninsular Siam. 
Type in the British Museum (Natural 
History). 
I have studied specimens in the British Mu- 
seum collection from Biserat, Siam. The spe- 
cies probably occurs throughout Thailand and 
Malaya and possibly to the West through 
Burma and South India. Edwards recorded it 
from Methapalayam, S. India. 
Plecia manni Hardy 
Plecia manni Hardy, 1950, Hawaii. Ent. Soc. 
Proc. 14: 82-84, fig. 7a. 
Related to P. laffooni Hardy and to gurneyi 
Hardy and fits the descriptions of these species 
except for male genital characters and except 
that the cubital vein is rather sharply bent 
downward and the cubital cell Is narrower at 
the apex. The ninth sternum lacks the pair of 
slender rodlike submedian lobes which is 
characteristic of the other two species in this 
complex and the posterior median portion of 
the sternum Is developed into a large semi- 
membranous portion which is longer than the 
remainder of the segment and which extends 
two-thirds the length of the claspers. The 
aedeagus has a pair of strong, curved, and 
sharply pointed accessory structures which 
extend well beyond the apices of the claspers. 
For a complete description see the above 
reference and figure. 
Length: Body, 5.0 mm.; wings, 5.7 mm. 
type locality: Fulakora, Solomon Islands. 
Type in the Museum of Comparative 
Zoology. 
Plecia mayoensis Hardy 
Plecia mayoensis Hardy, 1950, Hawaii. Ent. Soc. 
Proc. 14: 84, fig. 8a, b. 
Fitting in the complex which has the thorax 
entirely rufous and distinguished by the male 
genital characters. The slender stemmed, capi- 
tate lobes at the apex of the ninth sternum will 
separate it from all known species of Plecia . 
The apical lobes extend beyond the apices of 
the claspers and to the tip of the aedeagus. 
The claspers are short and broad, obtuse at 
apices. The ninth tergum has a deep U-shaped 
cleft on hind margin, the lobes are rounded at 
apices. For a more complete description and 
figures, refer to the above reference. 
Length: Body, 9-0 mm.; wings, 8.5-9. 5 mm. 
