REVISIONARY CLASSIFICATION OF RUTILIINI 13 
male but present in female). In Formosia s.str. the whole anterior surface of the 
fore coxa is haired, this feature distinguishing the segregate from all other Rutiliini 
(in which the anterior surface is bare except near the apex). In the genus Prodia- 
phania some valuable specific characters are provided by the setae of the ventral 
surface of the hind femur, and in some species by a series of long setulae found on 
the ad surface of the hind metatarsi of the male (such setulae occur nowhere else in 
the Rutiliini). 
Abdominal chaetotaxy. The presence or absence of long strong setae on T5, of 
discal setae on the intermediate tergites, and of median marginal setae on T3 provide 
useful characters at various taxonomic levels. The bristling of the inner ventral 
ends of the tergites, where they nearly meet in the mid line of the abdominal venter, 
varies much in strength and is sometimes spiniform; the direction of these setae, 
whether pointing downwards (as in Formosia s.l.) or mainly backwards and only 
slightly downwards (as in most other genera) has some value as a character at 
genericlevel. The arrangement and nature of the vestiture of T5 are often especially 
important, some segregates showing long haphazardly arranged setae, others one or 
two regular transverse rows, and others having little more than sparse weak hairing; 
some unusual species from the Philippines show short stubby setae irregularly in- 
serted over most of T5. In many forms the abdominal chaetotaxy is exceptionally 
strongly spiniform, but there are various degrees of ‘spiniformity’ in different genus- 
group taxa and the spinous setae cannot in themselves be used as a taxonomic 
character. 
Hairing. The presence or absence, or extent, of hairing on different parts of the 
body can provide valuable taxonomic characters at species-group, or genus-group 
levels. In Rutilia s.1., for example, a valuable character for distinguishing the 
subgenera Chrysorutilia and Ameniamima from other subgenera (and indeed from 
all other Rutiliini) is the extent of hairing on the pteropleuron; in these segregates 
the hairing on the pteropleuron extends well forwards on the sclerite, reaching to a 
level much in front of the posterior stpl seta (Text-fig. 19), whereas in other Rutiliines 
the anterior half of the pteropleuron is bare and there is virtually no hairing in front 
of the level of the posterior stp/ seta (Text-fig. 20). In Formosia s.str. the whole 
anterior surface of the fore coxa is haired, this feature distinguishing the segregate 
from all the other Rutiliini (in which the anterior surface of the fore coxa is bare 
except near the apex). Bare or haired parafacials distinguish many closely allied 
species, and some genus-group segregates contain only species having fully haired 
parafacials (e.g. Chrysorutilia). The barette is completely haired in nearly all 
Rutiliines but some Chetogaster species have the hindmost part of the barette bare; 
the type-species of Chetogaster and some closely allied species show a minute tuft of 
fine hairs on the mediotergite beneath the lower calypter (infrasquamal setulae), but 
| the mediotergite is totally bare in all other forms. Rutiliini normally have the 
propleuron thickly haired, but very rare individual specimens (therefore no taxo- 
nomic significance) have it bare. 
The most important taxonomic characters of the hairing lie in the postalar wall 
and the suprasquamal ridge (Text-figs 21-25), both of which may be haired (but 
