378 
M.S. Harvey 
Poorginup Swamp, W.A. (Figure 52). I revisited the 
type locality during August 1987, and found that 
the swamp had dried to a muddy quagmire which 
apparently sustained no macroinvertebrate fauna. 
Limited attempts were made to dig into the mud 
to ascertain whether nymphal mites had moved 
down into the hyporheion, but these proved 
unsuccessful. Due to the clearing of the natural 
vegetation around the swamp for farmland, there 
is a serious threat that if the swamp does refill at a 
later date, it could simply refill with saline water, 
as has at least one other lake in the Lake Muir 
complex (of which Poorginup is the smallest and 
most pristine). Like Pseudohydryphantes doegi 
Harvey (Harvey 1987), Acercella poorginup has not 
been collected at any other site, despite a fairly 
large collecting effort in the southwest over recent 
years, and it is possible that both species are 
extinct. 
This species has recently been placed on 
Schedule 1 of the Protected Invertebrate Fauna 
under the Wildlife Conservation Act 1950 (Minson 
1994). 
Etymology 
The specific epithet is a noun in apposition taken 
from the type locality. 
Subfamily Pioninae Thor 
Fiona Koch 
Nesaea Koch, 1836: 21. Junior homonym of Nesaea 
Leach, 1814 (Crustacea) and Nesaea Risso, 1826 
(Mollusca). Type species: Nesaea rosea Koch, 
1836, by subsequent designation of Koch (1842). 
Fiona Koch, 1842: 13; K.O. Viets, 1987: 605. Type 
species: Nesaea ovata Koch, 1836 (junior 
subjective synonym of Nesaea variabilis Koch, 
