Some intro, just to get going!
The way I always taught insect’s morphology to students was to never get frustrated with definitions and hard scientific names. Remember evolution is modification of same body parts into different forms. For instance what we call “Hypostomium” (part of the mouth part) in one insect is called “Mentum” in another. That is mentum is modified form of hypostomia. Always remember that insects are arthropods and this means that their body is segmented, so many in fact. So with many segments come many names. Also, remember entomologists love nothing better than to name things, so over time with new insects species came along new morphological names. Therefore, to avoid any confusion we always stick with basic morphological features of the insects.
In science besides learning the concepts we need to memorize the terms and the best way for memorization is by repetition. Most professors know their basics because they teach them over and over. So if we only read about the insect morphological characters once, chances of learning them is very low. However, through repetition and revisiting the same feature we’ll increase our chances. I also found out that by drawing the segments and teaching it to yourself you can achieve the familiarity much faster. So for every post I present on insect morphology I showcase my own drawings, no matter how bad they look. My drawings most likely represent a mutated insects but I love them. This will pretty much take care of memorization. Combine this with understanding the concept and you can ace it. For every morphological character that you learn try to understand what that character does for the insect. Understanding the function of segment is the best way to learn the name and position of it. We start this post with head’s morphology.
If you are interested in detail insect morphology, 2 of my favourite insect books can help you out. An Introduction to the study of Insects 7th edition by Johnson and Triplehorn (2005) is a great book for Insects fan. There is also a great article on history of the book by Triplehorn (2009). My absolute favourite book on Insects morphology is the Manual of Insect Morphology by DuPorte (1959). However, I think later editions of this book are also available.
A) Head
Part 1: Sclerites
As you may recall I mentioned that Insects are arthropods and as such their body is segmented. If we are to avoid all the detailed morphological features of the head and instead concentrate on head as different segments, sclerites or hard exoskeleton parts of arthropods, we can have a better understanding of the head altogether. These sclerites are where antennae and mouth parts attach. Just like us, insects have front and back cranium of the head. Each of these is divided by series of sutures or stitches. Remember the segments must be attached or stitched. In the back we have Occipital region consist of sclerites “Occiput” separated from front by Occipital suture and Postocciput separated from Occiput by Postoccipital suture. Think of these as equivalent of your neck that holds the head. Facial or “Frontoparietal region” is the front. Front is one big sclerite also divided to many parts by these so called sutures. It has pair of compound eyes on the side, antennal sockets in front of the compound eyes and one or two ocelli (simple eyes). Ventrally (lower side) two vertical sutures called “Frontogenal sutures” divide the front into “Frontoclypeus sclerite” in front and two “Gena” on the side. Think of these as the upper part of your mouth and nose, and your cheeks. Frontoclypeus sclerite is further divided into frons on top and clypeus at the bottom by the same suture.
Redrawn from DuPorte (1959)
Words to remember!
Clypeus: From the latin clipeus meaning round shield
Gena: From latin word meaning Cheek.
Occipital: From Middle English name that is coming from old latin Oc = Before + ciput = Caput or head expansion.
Post: After. As in Postoccipital
Sclerites: Chitinous or calcareous hard parts.
Suture: Stitch
On the next post we will explore the mouth parts of the head
The way I always taught insect’s morphology to students was to never get frustrated with definitions and hard scientific names. Remember evolution is modification of same body parts into different forms. For instance what we call “Hypostomium” (part of the mouth part) in one insect is called “Mentum” in another. That is mentum is modified form of hypostomia. Always remember that insects are arthropods and this means that their body is segmented, so many in fact. So with many segments come many names. Also, remember entomologists love nothing better than to name things, so over time with new insects species came along new morphological names. Therefore, to avoid any confusion we always stick with basic morphological features of the insects.
In science besides learning the concepts we need to memorize the terms and the best way for memorization is by repetition. Most professors know their basics because they teach them over and over. So if we only read about the insect morphological characters once, chances of learning them is very low. However, through repetition and revisiting the same feature we’ll increase our chances. I also found out that by drawing the segments and teaching it to yourself you can achieve the familiarity much faster. So for every post I present on insect morphology I showcase my own drawings, no matter how bad they look. My drawings most likely represent a mutated insects but I love them. This will pretty much take care of memorization. Combine this with understanding the concept and you can ace it. For every morphological character that you learn try to understand what that character does for the insect. Understanding the function of segment is the best way to learn the name and position of it. We start this post with head’s morphology.
If you are interested in detail insect morphology, 2 of my favourite insect books can help you out. An Introduction to the study of Insects 7th edition by Johnson and Triplehorn (2005) is a great book for Insects fan. There is also a great article on history of the book by Triplehorn (2009). My absolute favourite book on Insects morphology is the Manual of Insect Morphology by DuPorte (1959). However, I think later editions of this book are also available.
A) Head
Part 1: Sclerites
As you may recall I mentioned that Insects are arthropods and as such their body is segmented. If we are to avoid all the detailed morphological features of the head and instead concentrate on head as different segments, sclerites or hard exoskeleton parts of arthropods, we can have a better understanding of the head altogether. These sclerites are where antennae and mouth parts attach. Just like us, insects have front and back cranium of the head. Each of these is divided by series of sutures or stitches. Remember the segments must be attached or stitched. In the back we have Occipital region consist of sclerites “Occiput” separated from front by Occipital suture and Postocciput separated from Occiput by Postoccipital suture. Think of these as equivalent of your neck that holds the head. Facial or “Frontoparietal region” is the front. Front is one big sclerite also divided to many parts by these so called sutures. It has pair of compound eyes on the side, antennal sockets in front of the compound eyes and one or two ocelli (simple eyes). Ventrally (lower side) two vertical sutures called “Frontogenal sutures” divide the front into “Frontoclypeus sclerite” in front and two “Gena” on the side. Think of these as the upper part of your mouth and nose, and your cheeks. Frontoclypeus sclerite is further divided into frons on top and clypeus at the bottom by the same suture.
Redrawn from DuPorte (1959)
Words to remember!
Clypeus: From the latin clipeus meaning round shield
Gena: From latin word meaning Cheek.
Occipital: From Middle English name that is coming from old latin Oc = Before + ciput = Caput or head expansion.
Post: After. As in Postoccipital
Sclerites: Chitinous or calcareous hard parts.
Suture: Stitch
On the next post we will explore the mouth parts of the head