Limnesiidae from northern and Western Australia 
Park, 27 July 1994; 9 S, 6 9 , 1 nymph, small 
stream. Butterfly Gorge, Katherine Gorge National 
Park, 27 July 1994; 2 d,l 9 , 1 nymph, Katherine 
River, near visitor's center, Katherine Gorge 
National Park, 28 July 1994; 1 9 , pond Chinaman 
Creek, 16 km south of Katherine, 29 July 1994; 6 <3, 
7 9 , 1 nymph, plunge pool Edith Falls, Katherine 
Gorge National Park, 30 July 1994; 3 6, 1 9 , 
Douglas River, at Douglas Hot Springs, 1 August 
1994; 1 6, 1 9 , ponds Ormiston Gorge, Ormiston 
Gorge National Park, 6 August 1994; 3 <?, 
waterhole Ormiston Gorge, Ormiston National 
Park, 6 August 1994. 
Western Australia: 8 S, 26 9 , 3 nymphs, 
Fortescue Falls (pool), Hamersley Range National 
Park, 11 August 1994; 5 d, 12 9 , 12 nymphs, pond 
Dales Gorge, Hamersley Range National Park, 12 
August 1994; 14 d, 12 9 , 5 nymphs, pond 
Kalamina Gorge, near falls, Hamersley Range 
National Park, 13 August 1994; 2 d, streams 
originating in Chinderwariner Pool, Millstream- 
Chichester National Park, 15 August 1994; 4 
nymphs. Palm Pool, Millstream-Chichester 
National Park, 15 August 1994; 2 nymphs. Deep 
Reach Pool, Millstream-Chichester National Park, 
15 August 1994; 2 nymphs, western part Deep 
Reach Pool, Millstream-Chichester National Park, 
16 August 1994; 2 d, 2 9, Python Pool, Millstream- 
Chichester National Park, 17 August 1994; 5 d, 1 
9, Jones River, east of Roebume, 17 August 1994; 3 
d, 2 9,2 nymphs, Fortescue River, at crossing with 
North West Coastal Highway, 18 August 1994; 2 
d, Ashburton River, at crossing with North West 
Coastal Highway, 18 August 1994. 
Remarks 
In some populations, males and females 
possessing an aberrant number of acetabula, co¬ 
occur with specimens having the normal two pairs 
of three acetabula. The following aberrant numbers 
of acetabula have been recorded (males as well as 
females): 2+2, 2+3, 7+7 and 8+8. All these 
specimens are otherwise similar to L. parasolida, so 
I assigned them to that species. The number of 
acetabula is used for subgeneric splitting within 
the genus Limnesia, e.g. tetracetabulate species are 
assigned to Tetralimnesia. It is clear that the number 
of acetabula cannot be used for subgeneric 
splitting. Cook (1974) has pointed out the 
likelihood that unrelated species are lumped in 
subgenera of Limnesia. 
Occasionally, the IV-leg-5 of L. parasolida has two 
stiff swimming setae. Cook (1986) mentioned the 
occurrence of only one stiff setae on this leg 
segment. 
L. parasolida shows large variation in length. 
Females range from 320 to 1344 in length, the lower 
value belonging to a young female. Males ranged 
from 523 to 912. Cook (1986) gives the following 
349 
measurements: females 638-850, males 760-896. 
Small specimens usually have a short terminal seta 
on IV-leg-6, 77-84 in length. In larger specimens 
this seta measures 127-137. However, intermediate 
lengths do occur. It might be possible that more 
than one species is present, but morphological 
characters do not allow a separation. 
Distribution 
Previously reported from Northern Territory 
(Alice Springs area) (K.O. Viets, 1984) and 
Queensland (Cook, 1986; Smit, 1992). With the new 
records, it can be concluded that L. parasolida is a 
common species of the northern half of Australia. 
Limnesia (Limnesia) rubra sp. nov. 
Figures 2-4 
Material Examined 
Holotype 
d, plunge pool Edith Falls, Katherine Gorge 
National Park, Northern Territory, Australia, 30 
July 1994 (NTM). 
Para types 
1 d, 1 9 (ZMA), 1 9 (NTM), same data as 
holotype. 
Diagnosis 
Male acetabular plates forming a complete ring 
surrounding the gonopore, extensive secondary 
sclerotization around fourth coxal plates and 
genital field, first coxal plates fused medially, 
capitular bay deep, Glandula Limnesiae on third 
coxal plates and well separated from associated 
setae, peg-like seta on ventral margin of PII not on 
a tubercle, legs with swimming setae, chitinized 
parts coloured red. 
Description 
Male 
Body 1067 (989) long and 902 (873) wide; 
chitinized parts coloured red. Integument smooth. 
Dorsum with an elongated platelet, 136 (136) in 
length. Capitular bay deep, longer than medial 
margins of first coxal plates. First coxal plates 
fused medially. Glandula Limnesiae on third coxal 
plates, well separated from the associated setae. 
Extensive secondary sclerotization around fourth 
coxal plates and genital field, and to a lesser extent 
medial of third coxal plates and posterior of first 
coxal plates. Gonopore 136 (120) long, completely 
surrounded by acetabular plates. Genital field with 
two pairs of three acetabula, the most anterior pair 
elongated. Excretory pore between associated 
glandularia. Lengths of PI-PV: 29, 144, 91, 206, 60. 
