32 
THE PAN-PACIFIC ENTOMOLOGIST 
high; the usual pleural setae, including lower epimerals; wing venation similarto Rhexoza, 
costal-radial complex ending before middle of wing; M fork longer than stem; M, and M 2 
diverging to wing margin; setae dorsally on costal-radial complex; wing membrane beset 
with microtrichia. Male abdomen with 7 evident segments; 7 pair of spiracles; with 
modified 8th tergum; sterna absent on segments 1-4; small triangular sclerite on 5 and 6; 
terga present on 1-7; segment 7 modified; sternum 7 with bilobed posterior expansion, 
tergum 7 posteriorly deeply emarginate. Tergum 8 either bifurcate or truncate; genitalia 
with sclerotized penis, reduced penis valves and an elongate median process which may 
be the fused gonocoxites. Female abdomen with 7 segments; sternum absent on 1-6; 
sternum 7 sclerotized; terga 1-7 sclerotized. Segment 8 and terminalia of female very dif¬ 
ferent in the 2 included species. Tergum either divided or entire; cerci large or small, 8th 
valvifers present or absent. Type species of the genus: Akorhexoza dampfi (Duda). 
Diagnosis. —Length of costa between R x and R 3 greater than length 
of Rij abdominal segment 7 visible in males; males with tergum 7 not 
produced posteriorly, with an obvious tergum 8 and with sternum 7 
deeply emarginate posteriorly. 
The two included species can be distinguished readily. A. cactivora 
has tergum 8 apically truncate in the male and the female has paired 
posteriorly projecting, acute valvifers. A. dampfi has tergum 8 pro¬ 
duced into 2 posteriorly-directed points in the male and the female 
has apically rounded setose valvifers. 
Akorhexoza dampfi (Duda), new combination 
This species was redescribed in 1956 but some additional 
characters should be added to that redescription. 
Male. — Flagellomeres with about 13 setae in a single whorl in addition to microtrichia 
and campaniform sensilla; maxillary palpi 0.17 mm long: label la slender, nearly as long as 
palpi; rostrum long; occiput sparsely setose, with 3 campaniform sensilla on each side; 
cardo-stipites conspicuous, with about 18 setae on each side. 
Supraalar setae 13-21; preepisternals 16, anepisternals 23; upper episternals 13; 
subalars 21; subspiraculars 14-21 (2 large); lower epimerals 13; pedicellars 3-6. Wings 1.90- 
2.17mm long; Ri and R 3 with only dorsal setae; R 3 terminates before middle of wing; 
section 2 of costa about 1/3 longer than R,; membrane microtrichiose. Abdominal terga 2- 
6 rectangular, sparsely setose; tergum 1 anteriorly emarginate, narrower than succeeding 
terga; tergum 7 yellow, posteriorly emarginate, with long marginal setae and small sparse 
setae anteriorly; tergum 8 sclerotized, yellow-brown, posteriorly produced in 2 apically 
acute triangular processes; sterna 1-4 unsclerotized; sterna 5 and 6 small, (less than Vz 
width of terga) triangular, sparsely setose; sternum 7 deeply emarginate posteriorly, no 
tooth on posterior margin; no sternum 8. Genitalia with small setose penis valves; median 
ventral process with a few small marginal setae, penis conspicuous, sclerotized. 
Females.—Very like male in size and color. Cardo-stipites with 25 setae on each side. 
Supraalar setae 25-29; preepisternals 20; anepisternals 41; upper episternals 18; subalars 
25; subspiraculars 22 (3 large); lower epimerals 13, pediciliars 5. Wings as in male. 
Abdominal terga 1-6 as in male; tergum 7 with a crescent shaped posterior emargination; 
all tergites sparsely setose; sterna 1-6 not sclerotized, sternum 7 sclerotized, with a 
median rounded emargination, produced triangularly laterad of emargination. Tergum 8 
divided by large cerci, sparsely setose, microtrichiose, yellow; tergum 8 produced 
posteriorly as two adjacent apically rounded, setose processes. Redescription based on 1 
d, 1 9 from Brownsville, (Mexico) [sic] 10-21-48. 
