Australian Fruit Flies — Hardy 
117 
DACUS Fabricius sens. lat. 
Dacus Fabricius 1805. Syst. And. p. 272. 
Tridacus Bezzi 1915. Bui. Ent. Res. 6: 88. 
In a broad sense the genus Dacus includes 
those Dacini which possess the following 
combination of characters: no complete 
suture across the mesonotum; no strong 
spines on the front femora; the second por- 
tion of vein Mi +2 not bent downward; cell 
1st M2 not strongly narrowed behind the r-m 
crossvein; the abdomen not petiolated and 
the antennae not greatly elongated; the third 
segment not much longer than the face, and 
the antennae not two or more times longer 
than the face. All of the Australian Dacini, 
with the possible exception of Callantra 
aequalh (Coquillett) , are treated as Dacus sens, 
lat. by this writer. 
GENOTYPE: Dacus armatus Fabricius. 
KEY TO THE SUBGENERA OF DacuS 
(sens, lat.) known to occur 
IN AUSTRALIA^ 
1. Scutellum with four strong bristles. . 8 
Scutellum with two bristles 2 
2. Prescutellar bristles absent 3 
Prescutellars present 5 
3. Anterior supra-alar bristles absent. . . 4 
One pair of anterior supra-alars pres- 
ent Neodacus Perkins 
4. Crossvein r-m situated below the mid- 
dle of cell 1st M2 (discal cell) and 
distinctly before the apex of vein 
R1+2; three to four pairs of inferior 
fronto -orbital bristles present 
Heterodaculus n. subgen. 
Crossvein r-m beyond the middle of 
1st M2 and about opposite the end 
of vein R1+2; two pairs of inferior 
fronto-orbitals present . Daculus Speiser 
'^Callantra Walker has not been treated here since it 
was not represented in the Krauss collection. Its exact 
position is not clearly understood at the present time. 
The typical species of Callantra are very characteristic 
and certainly appear to be genetically distinct from 
Dacus. There are, however, borderline species which 
may link these two groups very closely. 
5. Anterior supra-alar bristles present. . . 6 
Anterior supra-alar bristles absent. . . 
. Afrodacus Bezzi 
6. Third tergum of male with a row of 
cilia on each side. . .Strumeta Walker 
Third tergum of male not ciliated ... 7 
7. Male wing with a well - developed 
supernumerary lobe (at apex of 
vein Cui+lstA) . . . .Asiadacus Perkins^ 
No distinct supernumerary lobe in 
male wing. ...... Gymnodacus Munro 
8. Prescutellar bristles present 9 
No prescutellar bristles 
Austrodacus Perkins 
9. Third tergum of male ciliated 10 
No cilia on sides of third tergum of 
male 11 
10. No anterior supra-alar bristles present; 
supernumerary lobe not developed 
in male wing. Hemtzeugodacus n. sub gen. 
Anterior supra-alar bristles present; 
supernumerary lobe well developed 
in male wing Zeugodacus Hendel 
11. Supernumerary lobe present in male 
wing Melanodacus Perkins 
No supernumerary lobe in male wing 
Paratridacus Shiraki 
Dacus (Afrodacus) Bezzi 
Afrodacus Bezzi 1924. Ann. S. Afr. Mus. 
19: 452. 
This subgenus is characterized by the ab- 
sence of the anterior supra-alar bristles. In 
other respects it is like the subgenus Strumeta. 
The group occupies a borderline position be- 
tween Strumeta and Daculus. Specimens of 
D. {Afrodacus) jarvisi (Tryon) have been 
studied which have a well- developed anterior 
supra-alar bristle on one side of the mesono- 
tum. These would occupy a position halfway 
between Afrodacus and Strumeta. Some aber- 
rant specimens of D. (Daculus) murrayi 
^Not known to occur in Australia. It is included 
here because of a difference of interpretation of writers. 
Perkins and May (1949) recently described Asiadacus 
calophylli. I have treated this in the subgenus Gymno- 
dacus. 
