Certain aphids and mites reproduce by telescoping generations, but do so in different ways (parthenogenesis and intercourse in utero, respectively), Hypothetically these methods could be combined. So this hypothetical arthropod reproduces like so:
- Virgin (parthenogenic female) impregnates herself with female (sexual female) offspring
- male comes along and fertilizes the females inside the virgin's womb
- females are born or eat their way out of their mother
- Females gestate male and virgin offspring
- Males and virgins are born, hatch from eggs, or eat their way out of their mother
- See step 1
How plausible is such a life cycle? What initial circumstances and selection pressures would lead to its development?