There we were, innocently walking from our cabana over to breakfast through the grass at Mama Noots Eco-Resort in Mayflower Bocawina National Park in the Stann Creek District of Belize. We hadn't bothered to put on any insect repellent for such a short walk, though of course we'd planned on slathering ourselves with it before our hike in the jungle after breakfast. All of a sudden, we noticed that we were attracting little black, gnat-like bugs, especially on our lower legs. It felt like they were biting us, though their bites didn't hurt or sting badly like a fire ant bite; it was just a passing annoyance, kind of like a no-see-um bite. After slapping at them awhile, we realized that where each one bit us, there was a small drop of blood.
As we arrived at the dining room, we ran into Liz, the proprietor, with one of the zip-line workers. We asked them about the bites, and they immediately recognized that they were made by some sort of fly. I could never understand exactly what they were saying; it sounded like "bottle fly", but maybe they'd called it "blood fly"? The latter was certainly fitting!
Here's how the bites looked the day I got bit. Not too bad yet.
By the time we got home from our late July trip, my legs were feeling a lot better. The swelling was gone and the itching was much less, but they still looked bad. It took a couple of weeks for all the little scabs to fall off.
As soon as we unpacked, we googled to find out more about these mystery flies, and although information was sparse, we did find a few things.
They are not bottle nor blood flies, nor are they (thank the gods) bot flies, the awful creatures whose larvae burrow under the skin of humans. They are sometimes referred to as bot-less flies because of this fact; but the correct name is BOTLASS Fly (Diptera: Simuliidae; blackflies, bloodsucking insects). They are a local type of blackfly and are apparently found primarily in the Silk Grass Creek area of Belize [ref: http://biological-diversity.info/Downloads/Mayflower_REA_s.pdf, search for botlass], which is very close to Mayflower Bocawina Park and Mama Noots. We found several mentions of them in blogs and forums solely in this area, but no mention of them elsewhere in Belize, nor have we encountered them anywhere else in the country where we have traveled fairly extensively.
This photo was taken on the last night of our trip, and you can see bites on my lower right leg.