Mem. Nat. Mus. Vict., 12, 1941. 
REVISION OF THE OENUS EUASTAGUS (CRAY- 
FISHES, FAMILY PARASTACIDAE), WITH NOTES 
ON THE DISTRIBUTION OF CERTAIN SPECIES.' 
By Ellen Clark 
Plates I-IX, Fig. 1. 
Introduction. 
In a previous paper (2) an attempt was made to clear up 
the synonjuny of the Australian Parastaeidae, but it was not 
possible to make a complete survey of the group as material 
from many districts was not available. Since that time, how- 
ever, much material from localities not previously repre- 
sented has been collected or received for identification. Special 
attention was given to obtaining specimens from New South 
Wales, the type locality of most species of the genus. 
With the material now available it has been possible to 
make a complete revision of the genus Euastaciis ; this revision 
has resulted in several alterations in nomenclature, the 
reasons for which are explained below. 
The full synomuny of each species is included with its 
description, and the distribution (as far as is known) is 
indicated. Since difficulties arose in finding suitable maps 
of Victoria to illustrate the distribution, two special maps 
(Plates VIII and IX) were compiled from data on plans 
prepared by the State Rivers and Water Supply Connnission 
and maps issued by the Geological Survey. 
Nomenclature. 
Genus EUASTAGUS Clark. 
Euastacus Clark, Mem. Nat. Mus. Vict., x, 1936, p. 10. 
Carapace spinous or tuberculate ; cervical groove deeply impressed, rounded. 
Rostral carinae spinous or tuberculate. Abdomen spinous or tuberculate; 
first segment with lateral lobes large and rounded. Telson more or less 
completely divided by a transverse suture, membranous posteriorly. Stems 
of podobranchs each produced into a broad wing-like expansion, covered by 
numerous long setae, terminated by sharply recurved hooks. 
Genotype : Euastacus elongatus Clark. 
In the original description of the genus the genotype was 
1. Results of work assisted by a grant from the Commonwealth Research and 
Endowment Fund. 
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