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 population had males and ephippial females, making possible the first description of the resting eggs, and male characteristics. The fringe of setae on the mid-region of the margin of the carapace in the female, thought to suggest a close relationship with Daphnia obtusa, is a primitive character shared with other genera in the Daphniidae, and which, therefore, does not provide sound information on relationships within the subgenus. Unique characteristics displayed in the ephippium (such as its sub-rectangular shape and the orientation of large egg chambers set at an angle to the dorsal margin of the carapace), and right angled margins of the fornices, that make it difficult to determine the precise affinities of D. jollyi within the subgenus Daphnia. This unique character set, and the species' relict distribution in a region of high and ancient endemicity, suggests D. jollyi may represent a separate and ancient lineage within the subgenus, presently found only in granite rock pools of slightly acid pH (6.0–6.5) in a restricted region of south-western Australia.
Daphnia jollyiAustraliaCladoceraAnomopodafreshwater rock poolsbiogeographytaxonomy