Jah. Benzie et Iae. Bayly, MALE AND EPHIPPIAL FEMALE DAPHNIA-JOLLYI PETKOVSKI, 1973 DISCOVERED IN WESTERN-AUSTRALIA AND THE PARTHENOGENETIC FEMALE REDESCRIBED, Hydrobiologia, 331(1-3), 1996, pp. 171-181
The rediscovery of Daphnia jollyi Petkovski 1973 in Western Australia
has allowed a more complete description of the female and has extended
the known range of the species within Western Australia. One populati
on had males and ephippial females, making possible the first descript
ion of the resting eggs, and male characteristics. The fringe of setae
on the mid-region of the margin of the carapace in the female, though
t to suggest a close relationship with Daphnia obtusa, is a primitive
character shared with other genera in the Daphniidae, and which, there
fore, does not provide sound information on relationships within the s
ubgenus. Unique characteristics displayed in the ephippium (such as it
s sub-rectangular shape and the orientation of large egg chambers set
at an angle to the dorsal margin of the carapace), and right angled ma
rgins of the fornices, that make it difficult to determine the precise
affinities of D. jollyi within the subgenus Daphnia. This unique char
acter set, and the species' relict distribution in a region of high an
d ancient endemicity, suggests D. jollyi may represent a separate and
ancient lineage within the subgenus, presently found only in granite r
ock pools of slightly acid pH (6.0-6.5) in a restricted region of sout
h-western Australia.