Sunday, August 25, 2013

Just When You Thought You Were Safe: Meet the Blood-Feeding Moths

Most people think of moths as  harmless little lepidopterians.  The familiar flutter of these creatures around a porchlight is something almost everyone has seen at some point in their life.  They are often thought of as "night butterflies", embracing the dark side as members of an order more often associated with sunshine and flowers.  Don't kid yourself into thinking that these little guys have yet to discover all the benefits of being blood-feeders.  Meet the genus Calyptera...these aren't your average noctuids!

Before you go jumping to conclusions that I'm making this up, let's consider how something as innocent as moths could have possibly made the leap to blood-sucking.  All lepidopterans (insects including butterflies, moths, and skippers) have a long proboscis used for sucking that unfurls when they are ready to feed.  Most of these animals use these siphoning mouthparts to feed on nectar and other plant fluids.  Some have adapted to feed on sugars and other plant products that require more than simple fluid-sucking.  These lepidopterans have the ability to actually pierce the tissues of the plants they feed on in order to extract the plants' yummy juices.

Over time, many species of lepidopterans have developed a taste for the tears (and other secretions) of a variety of mammals.  Most of the hosts for these lacrophagous lepidopterans are ungulates...often times domestic ungulates.  There are over 100 species of these insects that feed on ungulate secretions, but none of them have the ability to actually severe mammal tissue.  Though not really considered blood-feeders, some of these species have been known to suck blood from open wounds via feeding behaviors that resemble the way similar species feed on nectar.

Which brings us to our genus of choice: Calyptera. Unlike their sister genera, these moth do have the ability to actually pierce through the skin of vertebrates.  After piercing the skin, these moths are able to feast on the iron-rich, warm blood of their hosts.  The mouthparts of this animal are adapted for piercing the tough skins of plant fruits, which is how they were able to make the leap from plant-feeding to blood-feeding from an evolutionary perspective.  There are at least seven known species within the genus Calyptera that feed on the blood of vertebrates. Of those seven, five species have been documented to have fed on humans.

Appropriately, these moths are often called "vampire moths".  They only occur in the Old World as far as I can tell, but they do seem to be expanding their ranges.  They can be found from Malaysia to Sweden.  Unlike mosquitoes and most other blood-sucking arthropods, it is the male moths (as opposed to the females) that take the blood meals.  Wounds from a moth bite are apparently quite painful and remain sore for several days.  Luckily, these little scale-winged vampires aren't known vectors of any blood-borne diseases...yet.

Moral of the Story
The next time you see a sweet little moth fluttering about in the moonlight, remember they they could be more than the quiet, innocent moths you've always known.  Behind that fuzzy facade could lurk a hungry monster just waiting to catch you off guard and sucking your sweet life-blood!  Not so much if you are here in America, but definitely if you hanging out in Asia or Europe. :p Either way, you can't help but marvel at the beauty and audacity of a moth that lands on you gently, then pierces your skin for a tasty late-night snack.  Evolution, like nature herself, is a magnificent we can't help but fall in love with despite how terrifying it is that they created hematophagous owlet moths. o.O

Tuesday, August 6, 2013

The Clock Keeps Tickin’…Maybe I Will Too

SEM image of a tick's capitulum (head)
Dear Faithful Readers,

I'm sorry about my spotty posting this summer...things have been far busier than I'd ever expected!  This week, however, my excuse isn't that I've been busy, but rather that I've been sick.  I had a head cold that had me loopy for a few days.  Luckily I have an awesome friend who insisted that I take some Sudafed.  One pill pretty much fixed me up after a day of utter misery.  The point is, I missed blogging yet again, so here I am making up for lost time.  This is kind of a short one since I've been a bit under the weather, but I hope you enjoy it anyway!

As is my obsession for finding beauty in odd and often disgusting creatures, I’ve started doing a little work with ticks.  I caught several earlier this summer with no intention of actually taking the time to identify them.  Enter the Field Parasitology course.  Along with gear, the professor (the legendary, Dr. Scott Gardner) brought a stack of books.  Among the books was a mite and tick identification guide.  So, naturally, I felt I needed to pull out my preserved ticks and see what we had here.  I readied my station putting fresh sand in my dish and placing the book to my left and my notepad on the right.  After only a little bit of refreshing myself with tick terminology, I was able to get it keyed out to the genus Dermacentor.  As I read the species descriptions, I narrowed my specimen down to either D. andersoni or D. variabilis.  I was having a hard time differentiating the two, so I decided to wait.  A parasitologist who specializes in ectoparasites (Dr. Don Gettinger) would be coming to the station in a few days, so I just needed to have patience.

Ventral Anatomy of a Tick

Waiting for this expert’s opinion gave me a chance to think more about ticks.  You know, I’ve always hated them…stupid little blood suckers!  However, after forcing myself to look at them under the dissection microscope I started seeing them as less terrifying and more fascinating.  I recalled that way I had examined the tick for evidence of festoons and punctations, and how I had slowly come to realize just how intricate the anatomy of these simple creatures was.  My initial horror had morphed into silent appreciation as I had noted the bifid coxae and the set of 11 festoons.  Here I was again, privy to yet another stunning work in the glorious underground art gallery that Mother Nature had unfurled before my very eyes. 

As my time comes to an end here at the station and I return home to work on Lithuanian mummies and Mexican coprolites, I can say that I am honestly walking away with a new appreciation for yet another group of animals that most people find disgusting.  I’ve given my ticks to Dr. Gettinger and he should have them identified definitively here in a few weeks. I’m really excited about seeing to which species they belong!

Plans for next summer are far from set in stone, but perhaps if I have some time (and if I am out here with the same job I had this summer) I’ll be able to run a few tick drags and collect more of these creatures.  Maybe we could even see if they are carrying some of the bacteria that they have become famous for carrying!  Or maybe I won’t even get to come back here.  Either way, I’m glad to have had the opportunity to broaden my perspectives on the natural world this summer.  As the next few semesters roll on and my time as a PhD student ticks away, we shall see if I ever get the chance to “go ticking” myself!