MICROLEPIDOPTEBA OF NEW GUINEA 
35 
quite homologous with the labis of the Noctuidae, and of a narrow median 
rod, being the half of the transtilla proper, which we call median pro- 
jection ; coremat-a on seventh segment present. Female genitalia with 
seventh ventrite modified so as to form a plicate membraneous field 
clothed with very dense hairs or scales, forming the above mentioned 
expansible corethrogyne ; a large, mostly coiled cestum 2 ) and a dagger- 
like sign urn invariably present. (Explanation of the different parts is given 
in figs. 13 and 14). 
The genera of this tribe form distinct groups of species — as far as this 
can be expected in the Tortricidae, where most generic characters are 
considerably plastic — hut the species of each genus are rather variable 
as to the minor particulars of structure. The females can easily be re- 
cognised by the corethrogyne which is invariably present, and forms a 
feature unique in the tortricoid Lepidoptera. The males may be less easy 
of recognition superficially, but a simple glance at their genitalia with the 
peculiar, complicated tegumen and uncus is sufficient to ascertain their 
systematic position. The genitalia of both sexes in this tribe are rather 
uniform. 
The Zacoriscini form a typical feature of the Papuan fauna. Isotenes 
must be the oldest or the most atavistic of the four genera known at 
present. The inconspicuous species have typically tortricoid markings, and 
modest colouring, and are of nocturnal habits. Diphtheropyga is tran- 
sitional between Isotenes, and the truly striking Chionothremma and 
Zacorisca which both have changed to diurnal fife-habits, and apparently 
in connection with this, acquired conspicuous bright colouring, and glossy 
smooth scaling of wings and body. Chionothremma is endemic, and seems 
to be in a stage of rich development in the isolated region of Central 
New Guinea. 
Interesting is the distribution of Zacorisca (fig. 15). As far as is known, 
the species occur at high elevations: 800 to 3300 m. The genus is most 
numerous in New Guinea; outside this island it is fairly represented in the 
Moluccas, but is sparse elsewhere. This distribution may be summed up 
as follows: New Guinea: twelve species, Bismarck Islands: two, Moluccas: 
six, Philippine Islands: three, Celebes: one, Flores: one, Borneo: one sub- 
species (of the Papuan Z. toxopei), and Java: one species. The isolated and 
elevated habitats of these stragglers outside the Papuan region suggest 
that we have to do with relicts of an old fauna. 
The distribution of Isotenes is less limited than that of Zacorisca. The 
genus is well represented in New Guinea but a few species are widely 
scattered throughout the Archipelago and spread further than those of 
the latter genus, viz. western Australia (one species), Buru (one species), 
Java (two species — only in the mountains, not below 1000 meters); one 
of the Javanese species, Isotenes inae Diakonoff, is recorded from the 
2 ) of. Diakonoff, ZooI. Meded. Leiden, vol. 21, p. 123, 236, 1939. 
