Examining Lathyrus polyphyllus pods. Many pods with damaged seed. Found a larva in one of the damaged pods. Several pods in plants located 1/4 mile apart show similar damage. Many of the damaged pods show one small hole (about 1mm), one larger hole (3mm). The diameter of the collection container is slightly over 5cm.  In 2017 I found larvae in similarly damaged pods, but the larvae did not look like the "striped" larva in the photos provided with this question, and the 2017 larvae were of more uniform circumference end-to-end (with circumference seemingly less than the larva in the 2019 photos).  The 2017 larvae were uniform light cream with brown "head" whereas the larva in the photos provided with this 2019 observation is cream with pinkish/buff banding/striping, and has a black "head"

Regarding the photo showing the two unripened seeds and a single pod together with the larva.  Those seeds are from another pod that was undamaged (did not have any holes or larva).  The pod in the photo is also not the pod in which the larva was found, but is representative of the damaged pods (it shows the larger sized hole mentioned above).