Corixidae and Notonectidae of southern Western Australia 
187 
19 
Figures 18-20 Anisops elstoni Brooks, 6 , Cape Le Grand National Park: 18, front leg (scale line 0.5 mm); 19, rostral 
prong (scale line 0.5 mm); 20, stridulatory comb (scale line 0.25 mm). 
extending slightly in front of the anterior width of 
vertex. Greatest head width either as wide or 
wider than greatest width of pronotum. Maximum 
head width between 7.5-9.8x anterior width of 
vertex and 3x median head length. Synthlipsis 
wide varying between 0.6-0.9x anterior width of 
vertex. Median head length 0.6-0.7x median 
pronotal length. Pronotal width 2x median length, 
lateral margins almost straight and slightly 
divergent. Posterior margin medianly slightly 
emarginate. Facial tubercle slightly raised with 
short sparse greyish hairs. Rostral prong long and 
thin (Figure 16). Basal width of labrum subequal to 
median length with longer hairs. Stridulatory comb 
(Figure 17) 15 pegs, inner pegs appearing distally 
acuminate. Chaetotaxy of front leg (Figure 15). 
Female 
7.0-7.8 mm long; head width 1.68-1.84 mm; 
pronotal width 1.82-1.92 mm. 
Colour: similar to male. 
Structure: viewed dorsally lateral eye margins 
convergent. Greatest head width between 0.89- 
0.93x pronotal humeral width and between 2.8- 
3.2x anterior width of vertex. Head width between 
5.3-8.3x anterior width of vertex. Synthlipsis 
between 0.62-0.92x anterior width of vertex. 
Median pronotal length 1.3—1.7x median head 
length, pronotal humeral width 1.89-2.25x median 
length. Lateral pronotal margins straight, 
diverging, posterior margin medianly emarginate. 
Facial tubercle slightly raised, frons above facial 
tubercle with fine pale hairs. Labrum with a cluster 
of short fine hairs. Basal width of labrum subequal 
to median length. 
Remarks 
In Brooks (1951) this species keys out to leucothea 
Esaki and in Lansbury (1969) it keys out to 
occipitalis Breddin. The stridulatory comb of 
occipitalis has about 24-26 pegs and the dorsal 
margin of the front femur is sinuate distally 
whereas that of baylii is more or less straight. The 
rostral prong of both leucothea and occipitalis are 
wider basally than baylii which has a very narrow 
elongate rostral prong. 
Anisops elstoni Brooks 
Figures 18-20 
Anisops elstoni Brooks, 1951: 326-327; Lansbury, 
1964a: 58-59; Sweeney, 1965: 91; Lansbury, 
1978: 105-107. 
Material Examined 
Australia: Western Australia: 2 6, roadside 
pool, Pfeiffer's Road, 8 km from Many Peaks, 4 
July 1977; 2 d, roadside pool, 6 km S. of Northcliffe 
[locality 3 of Bayly (1992a)], 1977; 1 6, 1 5?, swamp 
800 m from Le Grand Beach camping ground. Cape 
Le Grand National Park, 33°58'S, 122°07'E, 25 June 
1990. 
Description 
Males and females 5.8 mm long. 
Colour: eyes dark brown. Pronotum and 
scutellum pale brownish yellow. Hemelytra 
hyaline, dorsal pigmentation showing through. 
Ventrally black including frons, facial tubercle and 
labrum. legs shining dark brown-black. 
