Litinsects

Litinsects #50: Month of Mites, Part 6   Here's to 50 posts!  And how cool is it that this milestone lines up, completely coincidentally, with the species I wrote my thesis on?   So, in my last post I told you about spider mites. They are crop pests found on plants all over the world. Now I want to introduce you (finally) to some “good” mites! The heroes that might finally be able to change the mite reputation: PREDATORY MITES, also known as phytoseiid mites from their family name Phytoseiidae.   A couple quick facts before I explain why they’re great:   There are a few thousand species of predatory mites. They live on plants and are found on all continents except Antarctica They are between 0.2-0.5 mm in size and usually have shiny, teardrop-shaped bodies All phytoseiid mites are EYELESS! They are light sensitive but they sense their prey purely through chemical cues. It has even been shown that these mites can localize prey by honing in on the chemical signals...

Litinsects #49: Month of Mites, Part 5 Let me introduce you to some pesky little dudes called spider mites. There are about 1200 species of spider mites and they are huge agricultural/commercial pests. The TWO-SPOTTED SPIDER MITE shown in these photos (named for, you guessed it, its two dark spots) is one of the most well-known and economically important pests worldwide because it feeds on hundreds of plant species. I worked with these mites as part of my master’s thesis and was able to witness firsthand how they can decimate plants if left uncontrolled!   So why are they called spider mites? Because they spin silk WEBBING that can cover entire plants. The webbing serves as protection for the colony from weather, desiccation, and pesticides but also protects from predators, who can’t maneuver through it very well   Spider mite females are larger, at around 0.5 mm and males are around 0.3 mm. The eggs are round and 0.15 mm in size. Just before hatching, the mites’ RED EYES are...

Litinsects #48:  Month of Mites, Part 4 One of the most well-known mite species, probably because they live so close to us, is the house dust mite. Just a warning, this one’s super interesting but slightly gross...   © Gilles San Martin Dust mites are microscopically small, 0.2-0.3 mm in size, and have a COSMOPOLITAN distribution. They are found pretty much everywhere humans live Dust is made up of dead human skin cells and also contains hair, dirt, mold spores, pollen, and other microscopic debris. Dust mites feed primarily on dead skin but don’t worry, they DON‘T BITE humans As I’m sure you’ve heard by now, our mattresses, pillows, carpets, and upholstered furniture are FULL of both living and dead dust mites. Since they love warmth, darkness, and humidity and because we shed plenty of dead skin cells while we sleep, our beds are pretty much the ideal place for them to live! Dust mites are well known because they are associated with allergies in about 1-2% of the world popul...

Litinsects #47: Varroa Mites Month of Mites, Part 3 We are now onto some mites that are kind of a bummer: VARROA MITES. These are external parasites of honey bees and they are capable of massive damage to hives. Let’s start with the basics: © Scott Bauer Varroa destructor mites are 1-2 mm in size, usually wider than they are long. They are flattened to fit between the abdominal plates of bees, where they feed The mites puncture the body and feed on the body fat tissues of larval, pupal, and adult bees. They reduce bee life span and leave hosts weakened with wounds that may be susceptible to other infections Varroa is also a VECTOR for numerous viruses that have a negative effect on bees including deformed wing virus Although they now have an almost global distribution, these parasites are native to Asia and Western honey bees (Apis mellifera) are not actually their native hosts! Some Asian honey bees (the natural hosts) are believed to have developed some resistance to the mites but Ap...

Litinsects #46: Ticks Month of Mites 2 Today I’m talking about TICKS, which are actually a subset of mites that live an ECTOPARASITIC lifestyle (outside the body) and feed exclusively on blood. Most people think of mammals when they think of tick victims (tick-tims? ) but birds, reptiles, and even amphibians can get ticks too! The group is divided into hard and soft ticks. HARD TICKS have an inflexible plate, or SCUTUM, on their backs and, when viewed from above, you can see their mouthparts. SOFT TICKS don’t have a scutum and their mouthparts are hidden when viewed from above. Hard ticks (the ones you’ll generally encounter) are usually found in fields, vegetated areas, and woodlands, while soft ticks are found in animal dens, burrows, or caves. Ticks possess HALLER’S ORGANS, which are sensory structures located on their first pair of legs that detect body heat, exhaled carbon dioxide, moisture, and vibrations, all of which they use to locate hosts. Ticks will crawl up stems or tall g...

Litinsects #45: Demodex Mites Month of Mites, Part1 Let’s start the mites off right! Today’s post is about DEMODEX mites, also known as (drum roll please) face mites/eyelash mites! And if you believe that ignorance is bliss then I suggest you stop reading now... just kidding, you totally want to know this, I swear. © Palopoli et al. Demodex are a group of mites that live in the hair follicles of mammals. There are two species of Demodex that live on humans and, in fact, cannot survive anywhere else! The first, Demodex folliculorum , measures around 0.3 mm and lives inside hair follicles. The other, Demodex brevis , is around 0.1-0.2 mm and lives in sebaceous glands inside hair follicles (these are the glands that produce your skin oil, known as sebum). Both species feed on dead skin cells and oils inside your pores. Now when I say “your”, I mean literally YOURS... (probably). It used to be thought that they were not so prevalent but more recent studies have found the prevalence ...

Litinsects #44: Intro to Mites If you were to ask me which group of creepy-crawlies gets the worst reputation due to the lifestyles of just a portion of its members, I would absolutely say the mites. People only seem to know about the “bad” mites: ticks, dust mites, those little mites that live on your face (what’s that, you don’t know about face mites yet? Well I can’t wait to tell you about them)... But the fact is, the majority of mite species are ones that are harmless to humans, ones you will probably never hear about and never encounter even though there are an unfathomable number of these crazy-looking creatures all around us. Welcome to my MONTH OF MITES! Even though they’re not insects, I still think they’re super cool and would love to spread some fun facts, even about species that we may not like very much. <http://idtools.org/id/mites/invasive_mite/Invasive_Mite_Identification/key/Major_Mite_taxa/Media/Html/0001About.htm>   First off, let’s get to kno...