Skip to main content

#45: Demodex Mites

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 to be at almost 100% in some human populations! As you can imagine, more recent advancements of techniques for testing for mite DNA (because where there’s mite DNA, there are mites!) turns out a much higher prevalence than traditional methods of “let’s look at some samples under a microscope and see if we find any mites”.

  • Believe it or not, both these mite species can be considered COMMENSALISTS. Commensalism is a type of symbiosis (aka, a close interaction between two or more species) that benefits one party and is neither beneficial nor harmful to the other. In other words, Demodex have it pretty good living on your face, whereas you (maybe up until you heard about them) probably couldn’t have cared less...
  • However, when present in very high densities, these mites can cause DEMODICOSIS (red, itchy, or scaly skin) or worsen pre-existing skin conditions such as rosacea, dermatitis, and acne. So some sources do refer to Demodex as parasites...
  • These mites are transmitted through close contact of infested skin. So pretty much any time two people’s faces touch, they could be swapping mites
  • Both Demodex species prefer the “oilier” parts of the body, hence they are usually found on the face, but they also survive in other areas. They are long and thin, adapted to live in tight pores
  • Individuals position themselves head downward inside the follicle. There can be up to 6 mites living inside a pore at a time! And the dead mites? I hate to break it to you, but they just decompose on your face...
  • Demodex mites can travel 8-16 mm per hour and yes, they actually do move around your face at night looking for mates! (I would so love to know whether you can feel the mites moving but I found no info on this)

So next time you are feeling lonely, just remember you’re never really alone. You’ll always have your mites.

Labels:

Comments

Post a Comment

Popular posts from this blog

#8: Butterfly Wings

Litinsects #8: Butterfly Wings Have you ever heard that you shouldn’t touch a butterfly’s wings or it will die? Well why is that...? Who remembers what I explained yesterday about Latin names? Butterflies and moths belong to the group LEPIDOPTERA, from the Greek words lepis for scale and pteron for wing. You probably guessed it already: butterfly wings are covered in SCALES! (Anyone starting to see a pattern with the names here? 😉 ) Butterfly scales are actually modified, flattened SETAE (aka hairs) that either partially or entirely cover the wings of most species. Some look like roof tiles, like on this here monarch, while some look more thread-like Scales protect and insulate the insect, but underneath the wing is actually transparent! Some species, like the GLASSWING BUTTERFLY, lack scales and have totally amazing see-through wings! Scales are responsible for the coloration of butterfly wings in one of two ways. First of all, scales contain
Post a Comment
Read more

#60: Cockroaches

Litinsects #60: Cockroaches Cockroaches belong to the order BLATTODEA, which is derived from the Greek word “blatta” meaning cockroach. Did you know that the Blattodea contains cockroaches AND termites? That’s right; termites are actually considered a specialized group of cockroaches! They used to be classified in an entirely different order of insects but recent genetic studies found a closer relation to cockroaches than previously thought. -Roaches are characterized by their broad, flat bodies. They have long antennae and generalized chewing mouthparts. In contrast to many other insects, which have 3, cockroaches have only 2 ocelli (or simple eyes) -Most people consider roaches to be disgusting, disease-spreading pests. But of 4,500 species, only 30 live in human habitats and are considered pests -The common name is derived from the Spanish word for the insect, “cucaracha” -Cockroaches can be found in a wide variety of habitats around the world. Many live in the tropics but
Post a Comment
Read more

#41: Centipedes

© Didier Descouens Litinsects #41: Centipedes Now for the centipedes! If you missed my last post on millipedes, go back and check it out... So how do they differ from millipedes? Unlike millipedes, which are mainly detritivores, centipedes are VENOMOUS and PREDATORY. Millipedes have a more cylindrical body whereas centipedes are usually flattened. Millipedes have (as the Latin name Diplopoda suggests) two leg pair per body segment but centipedes have only one pair per segment. As for the number of legs, centipedes can range from having 15 to about 170 pairs; this is generally fewer than millipedes have but it’s not always the case. Finally, millipedes tend to travel pretty slowly while centipedes are fast runners. Centipedes make up the group CHILOPODA. In Greek, “khelios” means lip and “poda” means foot. The name describes a pair of pincer-like appendages called FORCIPULES, located right behind the head, with which they inject venom to paralyze prey. So the “bite” of a centipe
Post a Comment
Read more