First Cecropia Caterpillar Ecdyses to Third Instar

Our oldest second instar Cecropia caterpillar (Hyalophora cecropia) ecdysed into third instar.

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Today a lot of Cecropia caterpillars entered apolysis- 19 by midnight, not including the one from yesterday. The photos above show several caterpillars in apolysis. The left most showing the one from yesterday at about 5:30 PM, while the other two show four individuals reared on apple.
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At about 8:10 PM we checked on the caterpillars again and discovered that the one that was in apolysis yesterday (left most photo above), had just molted into third instar, probably within the past half hour based on the moistness of its new cuticle. It was quite challenging getting clear photos of it at this time of day, but here they are below, taken at 8:17 PM. Though it has still not tanned, it's tubercles are now brightly colored: one blue pair (T1) and two large red pairs (T2-3) of dorsal thoracic tubercles; one large yellow pair (A1) followed by six more yellow pairs (A2-7) of dorsal abdominal tubercles plus a large middorsal yellow tubercle on A8 followed by two small pairs of blue dorsal abdominal tubercles on A9-10; eleven small blue pairs of lateral tubercles along both sides of the body (T1-A8); and three small black lateral thoracic tubercles near the true legs on both sides followed by two even smaller black lateral abdominal tubercles on A1 and A2. In addition, the black spikes on the tips are much longer and easier to see than in the second instar. Each tubercle is tipped with a ring of five black spikes a sixth center spike on the six dorsal thoracic tubercles, and a ring of six on the large middorsal tubercle on A8; however, it is too difficult to see how many hairs are on the row of small thoracic tubercles on the sides of the body (looks like just 1?). Between the tubercles are rows of black non-uniform shapes (ovals/circles/diamonds?), two per segment from T1-A9, which were there in second instar as well. The body color (including the head capsule) is now a yellowish green from a bright yellow, and should probably turn darker once the cuticle has finished tanning (probably a bluish green?). We will see how it looks in the coming days, and it's body color may still change throughout the instar as it gets bigger and fills with foliage.

For the record, today is the 14th day after the first caterpillars hatched and marks the end of second instar for the oldest individual, which lasted for roughly 6 days and 1-2 hours from 6/14-6/20. Recall that first instar for the oldest individuals lasted for roughly seven days and 6 hours from 6/7-6/14.

- Alan