6 STUTTGARTER BEITRAGE ZUR NATURKUNDE Ser. A, Nr. 622 
eral species have been recorded from the Philippines (5 spp., BocAk, 1999) and from 
Great Sundas (1 sp., for synonymy see D. niger chapter 6.). The numbers of speci- 
mens representing each species in both large materials studied from the Museum of 
Natural and Cultural Heritage and the State Museum of Natural History in 
Stuttgart were generally low and therefore we can expect further species to be dis- 
covered in the studied area in the future. Similarly we can expect further species in 
Wallacea and Australia, whose fauna is poorly studied. 
Relationships within the genus. Although the Diatrichalus fauna of New 
Guinea represents approximately half of the known diversity of the genus and we 
cannot expect substantial improvement of our knowledge of the diversity of this 
group, it is nearly impossible to propose a robust hypothesis about the phylogeny at 
the species level using only morphological characters. I have found only some 
groups of species but because of their weak support I have not used them in the clas- 
sification. They would be defined first of all on the basis of the shape of the male 
genitalia and partly on the coloration. The known female genitalia which proved to 
be useful in other groups were uniform and the possibility of employing them was 
further lowered by the fact that females of many species are not known. 
The first group comprises species with an open ventral part of the phallus (Figs 
25-33). This character is considered to be primitive, because it is known from gen- 
era of the family Metriorrhynchinae, and therefore this group is supposed to be pa- 
raphyletic. It includes the group of dark coloured species without secondary costae 
(D. biroi and D. emarginatus), dark species with fully developed secondary costae 
(D. schawalleri) as well as brightly coloured species (D. rubricostatus, D. pallidi- 
humeralis, D. striatus, D. fasciatus, D. mancus, D. humeralis and D. bipunctatus). 
Only two species with at least part of the body brightly coloured show a different 
type of the phallus: the isolated D. secretus with the simple, tube like basal part of the 
phallus and D. sedlacekiae, which has the same type of phallus as the following 
group. The bright coloration of the body seemed to be a synapomorphy, when a 
draft of a character matrix was run on Hennig86, but all species from the Philippines 
are brightly coloured and they belong to the next species group involving represen- 
tatives with a ventral process of the phallus. The polarisation of bright coloration as 
a character supporting relationship in the genus would be therefore very ambiguous 
in a more complex analysis. 
A second group comprises all species with a closed ventral part of the phallus and 
with a process approximately in the middle of the phallus length (Figs 9-16, 19-22, 
35-42). Only two species from New Guinea from this group are not dark uniform; 
the brightly coloured D. sedlacekiae and light brown D. habbema, all remaining 
species are uniformly dark brown to black either with a blue, bronze or green metal- 
lic shine (D. cyanescens, D. parallelus, D. proprius, D. dentatus etc.) or without it (D. 
cerberus, D. tenimberensis, D. piper, D. sinuaticollis, D. fenestratus). The absence of 
secondary costae used earlier by KLEINE (1926) for proposing the genus Diatrichalus 
has been found in various groups when defined on the basis of male genitalia and it 
proved to be unsuitable for the classification. Moreover, there are many intermedi- 
ate states between weak, irregular, secondary costae and their complete absence. 
