Data from: Defecation in preparation for ecdysis drives microplastic clearance in cricket nymphs

Plastic pollution is widespread in both terrestrial and marine
environments, creating significant ecological concerns. Animals that
occupy lower trophic levels, like many small insects, can ingest and
retain plastics for extended periods before eliminating them. Ecdysis, or
moulting, occurs in arthropods during development and facilitates growth,
but its role in microplastic (MP) clearance, and whether it is impacted by
MPs, are largely unexplored. We used the cricket Gryllodes sigillatus to
examine how and when moulting influences MP clearance in a hemimetabolous
species known to ingest and tolerate MPs throughout development. We tested
two alternative hypotheses of how moulting influences MP clearance: (1)
that moulting of the gut lining removes MPs, or (2) that cessation of
feeding and/or purging frass before ecdysis occurs removes MPs. In doing
so, we also provide new evidence that cricket nymphs exhibit a cyclical
(cosinor) pattern of frass production associated with ecdysis. We found
that the events leading to ecdysis likely act synergistically to clear the
gut contents from crickets' digestive tracts, with the slowing and
cessation of feeding and the clearance of frass from the digestive tract
eliminating most MPs from the cricket’s gut before ecdysis. We also
observed that the timing of ecdysis and overall frass production remained
unaffected by continuous MP ingestion, whereas switching between MP and
non-MP diets caused modest changes in the timing of frass production
within an instar. Crickets are known to biofragment MPs into NPs, which,
with gut-clearing, likely allows them to deposit plastic-laden frass
rapidly and reduces the likelihood of upward trophic transfer by reducing
MP retention.