GUAVA SKIPPER - Phocides polybius lilea LIFE CYCLE STUDY

Guava Skippers - Phocides polybius lilea are fairly common in the Lower Rio Grande Valley (LRGV) of South Texas. The trick to easily locate them is to know where their caterpillar host/food plants, Guava - Psidium guayava, can be found. It is a beautiful spread-wing skipper, quite large, and well-marked.

On 10/25/2014, I observed a Guava Skipper ovipositing on the Guava that we have in our front yard. We have raised many Guava Skippers on this tree in the past, but I had never wanted to take the time to do a life history of a Guava Skipper, before. The difficulty with this critter is that it uses a tree, which means a lot of the study would have to take place outdoors. Also, the caterpillar contains itself inside a refugium, so if you want to see the caterpillar, you have to open the refugium. This means the caterpillar has to go through the slow process of closing the refugium, each time it is opened.

Also, the leaves where the caterpillar is working must be contained inside some sort of netting, to keep out wasps and other insects. We had a great, wet winter in the LRGV this year. We also had several cool, even cold days this year. I was always concerned that when I opened the refugium in wet or cold weather, the naturally sluggish caterpillar might not be able to enclose itself inside the shelter, and I would lose the caterpillar.

The caterpillar never went into true diapause, but there were several days in a row that the caterpillar did not grow at all. The caterpillar was in no way a voracious eater. As a matter of fact it ate very little. A couple of Guava farmers I know say they would never waste money on pesticides for their Guavas, because the caterpillars must eat very little. The Guava Skipper feeds late at night, not during the day. If one did not recognize the refugiums, one might not even know there were caterpillars on the Guava.

After a time, a pure white pruinescence formed on the caterpillar and remained for a few days, until it formed a pupae. It took a long time from egg laying to butterfly emergence. We did, indeed, have to buy a second Guava for the caterpillar. We kept this one in the house to prevent losing leaves and to try to keep the skipper from going into diapause.

From egg to emergence took 134 days. One huge disappointment: I looked at the chrysalis, checking for the butterfly to emerge. I looked again ~4 minutes later, and the butterfly was out and its wings were already about dried! It must have emerged as soon as I had turned away! Fortunately, I had been keeping track of a second Guava Skipper, whose egg was laid the same day as my study skipper. I did capture its emergence, so I used 5 photos from that butterfly, just to show how fast the process is from emergence to wings dried.

Guava - Psidium guayava, a tropical, fruit-bearing tree in the Myrtle Family. Guava is commonly found in the backyards and butterfly gardens of the LRGV. Many folks like the pear-like fruit. It is the host/caterpillar food plant for the Guava Skipper - Phocides polybius lilea. If you want to be sure you get Guava Skippers in your yard, all you need to do is plant a Guava.

Since our Guava Tree is only 2-3 years old, it has very few limbs. Naturally the Guava Skipper chose the middle of the longest limb on which to lay her eggs. I had to use this large insect observation enclosure to seal off the egg, and hopefully future larvae, from wasps and other preditory insects. The larva stayed inside this environment until the end of February.

Towards the end of January, we had to go to the nursery and purchase another Guava Tree. All the cold weather we had been having caused our existing tree to drop most of its leaves, with the remaining leaves turning yellow. David did not grumble too much about having to spend $28 on a caterpillar; afterall, I already had just over 3 months invested in this guy. When we brought the tree home, I snipped off the refugium from the old tree and transferred it to the new tree, using a bag tie. I was then able to use a much smaller, and more convenient insect sleeve to enclose the larvae. We kept the new tree indoors by a sunny glass door, so as not to expose the tree nor larvae to cold, and to try to prevent the larvae from going into diapause. Fortunately,the larvae immediately started feeding on the new tree.

11/3/2014, temp=84F-67F. Day-10 from when the egg was laid. Day-2 as a caterpillar. The caterpillar is 3mm long. The caterpillar has been roaming around and is now beginning to make its refugium.

11/3/2014, temp=84F-67F. Day-10 from when the egg was laid. Day-2 as a caterpillar. The caterpillar is 3mm long. The top flap of the refugium is now cut from the leaf, leaving a small conection (hinge).

11/3/2014, temp=84F-67F. Day-10 from when the egg was laid. Day-2 as a caterpillar. The caterpillar is 3mm long. The top flap of the refugium is now connected to the leaf with silk. The caterpillar is now tightening the silk in order to bend the flap over the leaf.

11/4/2014, temp=86F-66F. Day-11 from when the egg was laid. Day-3 as a caterpillar. The refugium is complete. The caterpillar will stay in the refugium, coming out only at night to feed, then returning. As the caterpillar out grows the refugium or the refugium becomes so dry and brittle that the caterpillar cannot work with it, the caterpillar will make a new refugium. The caterpillar always rests upside down on the flap of the refugium.

11/4/2014, temp=86F to 66F. Day-11 from when the egg was laid. Day-3 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 5mm long.

11/5/2014, temp=76F to 64F. Day-12 from when the egg was laid. Day-4 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 7mm long.

11/6/2014, temp=64F to 59F. Day-13 from when the egg was laid. Day-5 as a caterpillar. The refugium was opened, immediately after a rain, to measure the caterpillar. The caterpillar is 5mm long.

11/7/2014, temp=64F to 65F. Day-14 from when the egg was laid. Day-6 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 6mm long.

11/8/2014, temp=76F to 55F. Day-15 from when the egg was laid. Day-7 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 7mm long.

11/9/2014, temp=78F to 54F. Day-16 from when the egg was laid. Day-8 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 7mm long.

11/10/2014, temp=80F to 53F. Day-17 from when the egg was laid. Day-9 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 7mm long.

11/11/2014, temp=83F to 56F. Day-18 from when the egg was laid. Day-10 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 7mm long.

11/16/2014, temp=77F to 56F. Day-23 from when the egg was laid. Day-15 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 6mm long.

11/19/2014, temp=68F to 50F. Day-26 from when the egg was laid. Day-18 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 6mm long.

11/20/2014, temp=77F to 62F. Day-27 from when the egg was laid. Day-19 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 6mm long.

11/22/2014, temp=81F to 64F. Day-29 from when the egg was laid. Day-21 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 7mm long.

11/23/2014, temp=85F to 64F. Day-30 from when the egg was laid. Day-22 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 8mm long.

11/25/2014, temp=71F to 53F. Day-32 from when the egg was laid. Day-24 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 8mm long.

11/28/2014, temp=77F to 49F. Day-35 from when the egg was laid. Day-27 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 10mm long.

11/30/2014, temp=82F to 62F. Day-37 from when the egg was laid. Day-29 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 10mm long.

12/3/2014, temp=68F to 53F. Day-40 from when the egg was laid. Day-32 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 10mm long.

12/5/2014, temp=83F to 66F. Day-42 from when the egg was laid. Day-34 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 11mm long.

12/9/2014, temp=70F to 59F. Day-46 from when the egg was laid. Day-38 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 12mm long.

12/11/2014, temp=75F to 61F. Day-48 from when the egg was laid. Day-40 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 14mm long.

12/13/2014, temp=80F to 60F. Day-50 from when the egg was laid. Day-42 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 15mm long.

12/15/2014, temp=81F to 66F. Day-52 from when the egg was laid. Day-44 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 15mm long.

12/17/2014, temp=77F to 67F. Day-54 from when the egg was laid. Day-46 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 18mm long.

12/19/2014, temp=68F to 59F. Day-56 from when the egg was laid. Day-48 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 20mm long.

12/22/2014, temp=59F to 51F. Day-59 from when the egg was laid. Day-51 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 20mm long.

12/26/2014, temp=83F to 61F. Day-63 from when the egg was laid. Day-55 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 22mm long.

1/7/2015, temp=68F to 50F. Day-75 from when the egg was laid. Day-67 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 25mm long.

1/17/2015, temp=71F to 44F. Day-85 from when the egg was laid. Day-77 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 25mm long.

1/28/2015. Day-96 from when the egg was laid. Day-88 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 25mm long. The refugium with the caterpillar were removed from the outside Guava Tree, and the refugium was attached to a new Guava Tree, using a bag tie. The new Guava Tree was moved indoors, next to a large, sunny glass door.

2/8/2015. Day-107 from when the egg was laid. Day-99 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 40mm long. There has been no change in appearance of the caterpillar, until today. The caterpillar is covered in a snow white pruinescence.

2/11/2015. Day-110 from when the egg was laid. Day-102 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 40mm long. The caterpillar is covered in a snow white pruinescence.

2/12/2015. Day-111 from when the egg was laid. Day-103 as a caterpillar. The refugium was opened to measure the caterpillar. The caterpillar is 40mm long. The caterpillar is covered in a snow white pruinescence.

2/18/2015. Day-117 from when the egg was laid. Day-109 as a caterpillar. Day-1 as a pupae. The refugium was trimmed away to expose the pupae for photos. The caterpillar is 29mm long. The caterpillar has gone into a "J". The caterpillar has lost much of its dust-like pruinescence, while attaching itself to the refugium with a girdle. Between 2/12/2015 and 2/17/2015, there had been no change in appearance

3/7/2015 at 0715hrs. Day-134 from when the egg was laid. Day-18 as a pupae. The pupae darkened greatly, overnight. Having previously photographed other pupae at this stage, I know that emergence is just hours away.

3/7/2015 at 1717hrs. Day-134 from when the egg was laid. Day-18 as a pupae. The buttefly is breaking loose from the inside of the chrysalis; therefore, the chrysalis appears lighter.