Has spines similar to Gulf Fritillary caterpillars that feed on passiflora.

But the color is so different!

Many caterpillar species have a large palette of background colors (independent of spots or other patterning) depending on what exact plant they feed on, the time of year (brood number), and the instar stage (1,2,3...). I could not find any images of the Mexican Fritillary caterpillar and could find no matching Gulf Fritillary caterpillar base color. The spine pattern and plant would suggest some kind of fritillary.