Monday, April 17, 2017

Caterpillar news

I've got good news. And I've sad news. 

Two days ago, James spotted a  new-to-us caterpillar species on the kidneywood in our back yard. I got some shots and later nailed down the species: southern dogface (Zerene cesonia), which host on small-leaved plants in the legume family. How cool is that? I was thrilled! But, alas, I lost the images because I didn't have a memory card in my point-and-shoot. So I went back to reshoot the caterpillars yesterday. 
When I did, I found the fuzzy yellow both under a caterpillar and near another one. What were they? And how did they just show up out of nowhere?




Imagine my surprise when I returned again to show James and the caterpillar was DECIMATED! So what are these yellowy menaces? Read on if you're not squeamish. (I'm not sure I can even write about it. Nature can be so MEAN!)
The fuzzy yellow pills are the pupae of parasitic wasps, perhaps Cotesia sp. Basically, female wasps lay their eggs INSIDE of a caterpillar. The larvae grow and chew their way out of the caterpillar. (For a more detailed explanation, read "The Real life 'Alien'") Then they create their (fuzzy) cocoons either on the caterpillar or nearby. Later, I spotted a hornworm in the back yard loaded with white coccoons, a first observation for me, though I've seen photos of infested caterpillars.




And now turning to our Dutchman breeches (Thamnosma texana) in the back yard...we're currently hosting one lone black swallowtail (Papilio polyxenes) caterpillar. Poor guy...I poked him several times so I could photograph his orange osmeteria (lost those photos, too). Those are horn-like organs behind the head that can spray an awful-smelling chemical repellent. Yes, my fingers got sprayed, which I shared with James (you should have seen his scrunchy-faced reaction). Very interesting behavior! (The caterpillar, not James.)

Meanwhile, the bordered patch (Chlosyne lacinia) caterpillars on our sawtooth sunflowers are growing and changing in appearance. 

2 comments:

james hearn said...

Amazing!

Melody McMahon said...

Sheryl, yes, nature can be cruel but fascinating! Ugh! I also wonder how caterpillars find just the right leaves to eat! I found a Border Patch caterpillar on a little native passion vine leaf that was the last plant on the fence and was curious how they connected. Thanks again for the education of God's creation!

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