My N. ventricosa has been consistently producing 6+ inch long leaves for the past few months. They have been narrow, flat, and grow straight out and hang down over the sides of the pot. A few weeks ago, it started producing these short (3"), very curled leaves, some with tips that grow at a 180 degree angle from the base, and the tendrils also seem to be a lot more wavy. The plant continues to produce pitchers on the long straight leaves (the latest one hasn't opened yet and is nearly 5" tall), the curly leaves do have soon-to-be-pitcher buds on the tips, and the growing conditions haven't changed (other than warmer temperatures heading into spring). This was my first Nepenthes, so I'm not sure if something is wrong, if this is normal, or if this is a sign of upcoming upper pitcher production, etc.
Someone mentioned that it might be thrips, so I took a magnifying glass and took a look at both sides of all of the curly leaves and did not see anything obvious. Should they be fairly easy to see at, say, 2x magnification? Also, pests shouldn't cause a plant to suddenly produce significantly shorter leaves, would it?
Here is a picture of the plant:
Any advice would be great.