Glossary of entomological terms

To help those unfamiliar with some of the entomological terminology used in this web site to better understand it, I have provided here a glossary of relevant terms.  Not all of these words are specifically of an entomological nature, but they are directly related to the topics discussed in the site.


abdomen - The hindmost of the three main body divisions of an insect.  In scarab beetles, this part of the body is shielded by the elytra.
adaptation - Modification of an organism or its parts that makes it more fit for existence under the conditions of its environment.
antenna - Pair of segmented appendages located on an insect's head and usually sensory in function - the 'feelers'.
antennae - Plural of antenna.
bifurcated - Divided into two branches or parts, used to describe the form of the horns in some male scarabs.
cephahlic - Of or relating to the head.  In male scarabs, the horn which projects from the head is known as the "cephalic" horn.
cetoniinae - The subfamily of scarabs which contains the "flower" beetles.
cetoniine - A scarab which is a member of the subfamily cetoniinae.
cicindelid - A species which is a member of the beetle family Cicindelidae, the "tiger" beetles.
Cicindelidae - The family of beetles which contains the "tiger" beetles.
clypeus - A plate on the anterior median aspect of an insect's head.
Coleoptera - The name of the insect order that is the beetles.
compost - An organic material that consists primarily of decayed plant debris such as fallen leaves and wood.
composting - process by which plant debris becomes compost.
hardwood -
The wood of an angiospermous tree as distinguished from that of a coniferous tree.  Deciduous hardwoods shed and regrow their leaves annually, whereas coniferous ones are evergreen.
dorsal - Relating to the back or top side of an animal.
dynastine - A scarab which is a member of the subfamily dynastinae.
dynastinae - The subfamily of scarabs which contains the "rhinoceros" beetles.
elytra - The modified first pair of wings in a beetle, which fold down over the abdomen and protect the flight wings when not in use.
entomologist - A person who studies insects.
exoskeletal - Relating to the exoskeleton.
exoskeleton - Collectively, the external plates of the body wall in an insect.  The tough armor of a beetle is its exoskeleton.
euchirinae - The subfamily of scarabs which contains the "long-armed scarabs", endemic to Asia.
euchirinine - A scarab which is a member of the subfamily euchirinae.
genera - Plural of genus.
genus A category of biological classification ranking between the family and the species.
habitat - The place or environment where a plant or animal naturally or normally lives and grows.
head capsule - The hard, unified plate which makes up the exoskeleton of a scarab larva's head.
imago - The adult stage of an insect.
instar - The stage in an insect's life history between any two sheddings of the exoskeleton.
lamelliform - Composed of or furnished with lamellae.  Said of the antennae of scarab beetles, as they are of a manifold design which can be unfurled like the rays of a fan.
larva - Name given to a young insect which is markedly different from the adult.  The young stage of an insect which utilizes "complete metamorphosis" is referred to as a "larva", whereas the young stage of an insect that uses "incomplete" or "gradual" metamorphosis is called a "nymph".
larvae - Plural of larva.
mandibles - The jaws of an insect.
metamorphic - Of or relating to metamorphosis.
metamorphosing - The act of metamorphosis.
metamorphosis - A marked and more or less abrupt developmental change in the form or structure of an animal occurring subsequent to birth or hatching.  Scarabs undergo metamorphosis by converting their body tissues into the adult form during the pupal stage.
mulch - A material created by chopping/grinding leaves and/or wood into a fine, spreadable form that is less coarse and more workable.  In the captive rearing of scarab beetles, mulch is made by breaking down decayed wood and leaves originating from deciduous hardwood trees, and mixing the two together to form a breeding/rearing substrate.
ocelli - (plural of ocellus).  The simple eyes of insects, usually occurring in a group of three on the top of the head, although one or more may be absent from many insects.  In scarabs, only the larval stage has ocelli.  The adult stage has much more complex organs of vision called "compound" eyes which consist of numerous facets.
oviposition - To lay eggs -- used especially of insects.
pheromonal - Relating to pheromones.
pheromones - Chemical substances that are produced by an animal and serve especially as a stimulus to other individuals of the same species for one or more behavioral responses.  Female scarab beetles release pheromones to attract males.
predator - An animal that lives by predation upon other animals.  In nature, predation is the act of capturing and devouring other animals for food.
pronotal - Relating to the pronotum.
pronotum - The dorsal surface or sclerite of a beetle's 1st thoracic segment.  In scarabs, this structure is quite large and often supports horn-like projections.
pupa - The 3rd stage in the life history of insects which undergo "complete" metamorphosis, during which the larval body is rebuilt into that of the adult insect.  In scarabs, this stage is spent within a protective cell built of surrounding debris.  The pupa is capable of some rolling movement, but is not actually mobile.
pupae - Plural of pupa.
pupal cell - A protective structure built by scarabs and many other insects in which pupation is carried out.  Depending upon species, scarabs build their pupal cells either within decaying logs, compost piles, or in the ground.
pupate - To turn into and exist as a pupa.
pupating - The act of becoming a pupa.
pupation - The pupal duration.  The process of gradually transforming the larval tissues into the adult form during the pupal stage.
rutelinae - The subfamily of scarabs which contains the "shining leaf" beetles.
scarab - short for "scarabaeid") A beetle which is a member of the family Scarabaeidae.
Scarabaeidae - The family of beetles which contains the scarabs.
scarabaeinae - The subfamily of scarabs which contains the "dung" beetles.
scutellum - In beetles, the triangular dorsal plate that is situated between the pronotum and elytra.  It is an especially large and prominent feature in cetoniine scarabs.
setae - Slender, usually rigid or bristly hair-like structures which project from the exoskeleton of a beetle, insect or other arthropod.  They generally serve a tactile sensory function.
sexual dimorphism - When the sexes within a species exhibit obvious differences in color or structure.  In many scarabs, such as the dynastines, the physical difference between the sexes is quite extreme.
sexually dimorphic - The quality of exhibiting sexual dimorphism.
species - The basic unit of living things, consisting of a group of individuals which all look more or less alike and which can all breed with each other to produce another generation of similar creatures.  It is the category of biological classification ranking between the genus and the race, or "subspecies".
spermatophore - A capsule, packet, or mass enclosing spermatozoa extruded by the male and conveyed to the female in the insemination of various animals (especially invertebrates such as insects and other arthropods).
spermatozoa - a motile male gamete of an animal usually with rounded or elongate head and a long posterior flagellum.
spiracles - One of the breathing pores of an insect - openings of the tracheal system - through which diffusion of gases takes place. They usually occur on the third thoracic segment and all the abdominal.
subfamily - A sub-division of a family, containing genera which are visibly different enough in form to warrant a minor separation from the main family classification.
subspecies - A sub-division of a species, usually inhabiting a particular area: visibly different from other populations of the same species but still able to interbreed with them.
substrate - The base on which an organism lives.  In the captive breeding of most scarab beetles, substrate for use as a rearing compound is composed of a mixture of mulched, decayed hardwood and leaves.
tactile - Of or relating to the sense of touch.
tarsal - Relating to the tarsi.
tarsi - An insect's feet: primitively a single segment but consisting of several sharp segments which form claws in most living insects.
terraria - Plural of terrarium.
terrarium - A usually transparent enclosure for keeping or raising plants or usually small animals (as insects) indoors.
thoracic - Relating to the thorax.
thorax - The middle of the three major divisions of the insect body. The legs and wings (if present) are always attached to the thorax.
tracheal - Relating to the tracheae, which are a series of tiny tubes which permeate the insect body and carry gases to and from the various organs etc. They open to the air at the spiracles.
ventral - Being or located near or on the anterior or lower surface of an animal opposite the back.

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