[8] In oligotrophic lakes, D. pulex has little pigmentation, while it may become bright red in hypereutrophic waters, due to the production of haemoglobin.

Phantom midge larvae (Chaoborus) release kairomones – chemical cues – that induce the development of small, jagged protrusions on the head, known as "neck teeth",[11] which increase survivorship in the presence of the invertebrate predator, but at a cost – longer development time, for example – when those predators are not present.

[12] D. pulex ecology is shaped by nutrient availability and balance, which affects traits that mediate intra- and interspecific interactions.

[13] Low nutrient availability reduces both body size and growth rate, which, as noted above, regulates Daphnia relationships to predators.

As inferred from expressed sequence tag analysis, the average intron size found in D. pulex genes is 170 bp.

[17] The D. pulex genome has undergone extensive gene duplication followed by rapid paralog divergence and tandem rearrangement.

During both cyclic and obligate parthenogenesis a polar body is extruded during cell division indicating initiation of meiosis.