Found primarily on subgenus Passiflora (P. vitifolia, P. ambigua and P. oerstedii), this species has become quite rare at La Selva. In 2010-14 I found fewer than 10 of these beetles. On one occasion I found a Red Ptocadica flea beetle on a leaf of P. ambigua (an unusual occurrance) next to a Yellow Ptocadica flea beetle. The Red beetle was chewing a hole in the leaf petiole! Like its congeners Pt. bifasciata and Pt. "red", I expect this species to oviposit round eggs and for the larvae to eat foliage rather than stems. I predict the larvae will look like their congeners (see below) and will be found on subgenus Passiflora.
Yellow Ptocadica looks a lot like the yellow form of Pedilia that feeds on P. pittieri. Ptocadica are somewhat longer with a longer pronotum, and the legs and basal antenna segments are melanized. Pedilia basal antenna segments are clear and unpigmented, as are the legs. The species also looks like Black-tibia Parchicola. The eyes are ovate with the small end pointing to the top of the head, unlike Parchicola with symmetrical oval eyes. Parchicola also has the unique flattened rectangle at the posterior end of the pronotum, although this may be difficult to see in life. Ptocadica does not.
After death this species turns brown and, after a few months, becomes visually indistinguishable from the Red Ptocadica flea beetle. In museum collections these two species have the appearance of Ptocadica straminea. |