Secondary queens in the parthenogenetic termite Cavitermes tuberosus develop through a transitional helper stage

Area of Science:

• Entomology
• Developmental Biology
• Social Insects

Background:

• Asexual queen succession (AQS) is observed in some termite species, where immatures develop into secondary queens (neotenics).
• Understanding the ontogenetic origin of neotenics is crucial for comprehending reproductive strategies in termites with AQS.

Purpose of the Study:

• To elucidate the developmental pathways and origin of neotenics in the neotropical termite Cavitermes tuberosus.
• To investigate the role of parthenogenesis in neotenic production in this species.

Main Methods:

• Utilized morphometric and genetic tools to analyze offspring development in Cavitermes tuberosus.
• Examined developmental pathways based on sex and genetic origin, focusing on nymphal instars.

Main Results:

• Identified a nymphal developmental line leading to neotenic queens, originating from third and fourth instar nymphs termed "aspirants."
• Found that a significant proportion of these "aspirants" are produced via parthenogenesis.
• Observed that "aspirants" perform worker tasks and differentiate into neotenics upon queen death.

Conclusions:

• Neotenic queens in Cavitermes tuberosus develop from specific nymphal stages ("aspirants") that are often produced parthenogenetically.
• "Aspirants" serve as a demonstrable indicator of parthenogenesis in termite species where reproductive cores are inaccessible.