TAXONOMY OF TROMBICULIDS 
161 
Subfamily Gahrliepiinae Womersley 
=Walchiinae Ewing 
Diagnosis (as in Womersley, 1952:278; as in Wharton and Fuller, 1952:91 but excluding genera 
Walchiella and Pseudoschongastia which are here placed in the Trombiculinae). — Trombiculids whose larvae 
have no anteromedian or submedian setae on the scutum ; scutum frequently extending backwards with or 
without inclusion of dorsal setae; expanded sensillae; leg I 7-segmented, legs II and III 6-segmented; 
coxa III frequently with two or more setae ; no mastitarsala or mastitibiala III. Nymphs and Adults similar 
to those of Gunther ana and Doloisia (new subgenus, above), with anterior rod of crista shorter than distance 
between sensillary bases; sensillae barbed along almost whole length; tarsus I with a subapical dorsal 
stump-like papilla; tectum rounded or conical, finely denticulate. 
Remarks. — Out of a total of 53 larval species known to the writer, at least 20 have been 
correlated with their nymphs. On the basis of the close similarity between nymphs, Womersley 
has reduced the four known genera to subgenera of Gahrliepia sens. lat. Previous to this, 
Womersley and Heaslip (1943:136) had synonymised Schongastiella and Gateria with 
Gahrliepia on larval characters. Gahrliepiine material from Burma, Malaysia, and Africa 
is being studied in detail by Traub, who is also in favour of recognising the broad genus until 
further studies clarify matters (Traub and Evans, T. and Morrow). An important contribution 
is being made by Vercammen who has discovered true gahrliepiine larvae with toothed chelicers 
in the Belgian Congo and has bred them to the nymph — the nymphs appear to be typical 
gahrliepiines (Vercammen 1953, an d personal communication). 
All these and also other workers are aware of the artificial nature of most of the divisions 
made between the present genera. In effect, these divisions have been made in steps according 
to the number of setae on the scuta until larvae with many and variable numbers of setae have 
made further efforts unprofitable; a division has then been made on the marginal or non- 
marginal placing of the setae on the scutum. The position therefore is that four generic 
divisions of dubious validity have been reduced to four subgeneric divisions which are still 
doubtfully valid, pending a revision to be made on the basis of more detailed study of larval 
and nymphal material. The first step in this revision would be to ignore the existing subgenera 
completely and to attempt to rearrange the assemblage of known species in natural groups. 
The following groups suggest themselves to the writer but this grouping is emphatically 
tentative and its object is simply to stimulate thinking away from the established subgenera. 
This particular rearrangement is largely based on the scuta, but much more attention should 
be paid to the chaetotaxy of palps and legs, to distribution of species on hosts and in space. 
The presence or absence of eyes has been considered of importance but this now appears to be 
of limited value. The writer himself suspects that more than one valid larval genus will emerge 
from the temporary repository of the broad genus Gahrliepia , in which case it is possible that 
the old family name (Walchiinae) may be restored. 
(1) pingue-group, comprising (A) pmgwe-subgroup, with hrennani , enode , dispar unguis , 
lewthwaitei , morobensis, pingue, and (B) noz-subgroup, with americana, rioi, and n. sp. nr rioi. 
Members of subgroup A show some tendency to a posterior prolongation of the scutum, 
so that these species might in fact form a series with the turmalis-subgrowp (below) in which 
a distinct narrow tongue is developed. Similarly, members of subgroup B may either be 
grouped with those of A, or they may be taken to form the first of the bengalensis- series, in 
having the posterior margin broader and more evenly rounded (in a new species near rioi from 
Selangor, this margin is very much convex). 
(2) turmalis-ligula-group, comprising (A) turmalis- subgroup ( Walchia ) with rustica , 
turmalis , and n. gen. n. sp. Vercammen 1953 (in press), in which there is a distinct prolongation 
of the scutum to form a narrow tongue, while the chelicers show a tendency to develop a tooth 
or (in Vercammen’s species) teeth. The position of Vercammen’s species, including another 
mentioned below, is complicated by the fact that these two species have been obtained from 
MALAYA , No. 26 , 1953 
