26 
REMARKS. The original description of S. congener is insufficient 
(Koch, 1841). Lilljeborg (1900) was the first to describe it appropri- 
ately, though this author believes this species to be a variety of S. 
exspinosus. Most authors suppose S. congener to be asynonym of S. 
exspinosus (Sars, 1888; Fldéssner, 1972; Margaritora, 1985; Sharma 
& Michael, 1988) or a variety (subspecies) (Behning, 1941). But 
Sramek-Husek er al. (1962) regard it as a separate species. I believe 
the latter opinion to be correct because there is a morphological 
hiatus between S. exspinosus and S. congener in the number and size 
of spines on the postabdominal claw. In addition, these species are 
sympatric in Europe. 
S. (ACUTIROSTRATUS) species group 
Female (Fig. 35). Frons pointed. Ventral head margin concave. 
Rostrum long. Setules on inner side of posterior valve margin thick. 
Dorso-posterior valve angle without prominence or with rounded 
prominence. Two supra-anal angles. Basal pecten of postabdominal 
claw of 10-15 large, close-set spines, which increase in size distally. 
Male. Unknown. 
S. acutirostratus (King, 1853) 
Fig. 35 
Daphnia Elizabethae var. acuti-rostrata King, 1853b: 254; 
Simocephalus acutirostratus: Sars, 1896: 12;S. paradoxus Schédler, 
1877; S. vidyae Rane, 1983: 154; S. vidyae gajareae Rane, 1986: 
168. 
M.J. ORLOVA-BIENKOWSKAJA 
TYPE MATERIAL. ‘Type probably not indicated by King. Type local- 
ity: Australia, New South Wales, ponds in Denham Court. 
MATERIALEXAMINED. (Fig. 32) Australia, New South Wales, swamp 
26km east of Cobar, 31°30'S 146°7'E, 12. 12. 1973, leg. Timms: 
more than 20 2 9 ad., 20 2 9 juv. New South Wales, Casino, 28°52'S 
153°3'E, leg. Henry: 9 ad. New Caledonia, dam near La Foa, 21°50'S 
166°53'E, 8. 8. 1981, leg. De Deckker: 2 juv. Queensland, pool at 
the road side, 30. 6. 1974: 29 Qad., 52 Qjuv. Queensland, Lake 
Lalilee, 22°19'S 145°51'E, 22. 4. 1984, leg. Timms: 9 ad. Material in 
AM and AC. 
DIAGNOSIS. Measurements. 9 9 ad.: 1.0-3.0mm. 
Female. General body shape ovoid (Fig. 35). Frons with large sharp 
prominence. Dorso-posterior valve prominence distinct, separated 
above and below with shallow, wide depressions. Diameter of circle 
inscribed in it large. Dorsal margin with denticles. Proximal and 
distal supra-anal angles large, embayments of postabdomen deep, 
proximal angle rounded. 
DISTRIBUTION. (Fig. 32) This species is reported fran Australia 
(King, 1853b), Philippines (Mamaril & Fernando, 1978), India 
(Michael & Sharma, 1988), Sri-Lanka (Rajapaksa, 1981), China 
(Chiang & Du, 1979), Lake Tanganyika and Venezuela (Zoppi De 
Roa & Vasquez, 1991), but the name S. acutirostratus has been so 
often misused for other species that its range needs to be redefined. 
It occurs with certainty in Australia and South-East Asia. 
REMARKS. This species was originally described as a variety of S. 
elizabethae. The types are obviously lost. The original description 
and illustration (King, 1853b), allow identification of this remark- 
able species with certainty. Sars (1896) gives S. acutirostartus the 
rank of a species. 

Fig. 26  S. gibbosus, lectotype, parthenogenetic female. A, lateral view, B, postabdomen. 
