True Flies (Diptera)

The Diptera are known as the true flies and are characterised by one set of flying wings with the hind pair developed into halteres (II in 5), accelerometers which provide neural information on the orientation and changes to direction of the fly.  Flies are also characterised by the lack of chewing mouth parts, as they only consume liquid food sometimes by digesting it externally and sucking it up via a modified labelluma and labium (Lb in 9).

Parasitic Isopods

This chart appears to place a copepod (1) with parasitic representatives of the order Isopoda.  The Suborder Cymothoida and some other Isopod families parasitise as ectoparasites grazing on mucus and skin or as endoparasites sitting in the mouth/pharynx of a fish collecting food.  this chart shows some common body forms.  note how the legs are repeated at each segment compared to those of amphipods which are modified for different tasks on different segments (2-8).

Beetles II (Coleoptera)

The order with the most numerous species, the coleoptera make up about 40% of all insect species.  Known commonly as beetles their body plan doesn’t vary drastically within the order however homologous structures are often put to different uses.  This chart shows adult forms (5, 10, 14, 15 & 17) highlighting the segmentation of the body into the head (I), prothorax (II), mesothorax (III), metathorax (IV) and abdomen (V).  Two forms of larva are also illustrated; the scarabeiform larva (1) which usually reside within their food (eg. within a tree trunk) and the highly mobile elateriform larva (16) usually associated with ground dwelling and predatory forms.

Amphipods and Isopods

Arthrostraca was an order that included all species of Isopods and Amphipods because of their superficial similarities.  This combination of two groups was retained within a newer classification scheme as Edriophthalma and a sister taxa Mysidacea which have since been rejected in favour of the order Peracarida which encompasses all members which were previously in these two groups.  This chart shows the nervous system (blue), circulatory organ of the open blood system (pink), alimentary canal (yellow), digestive glands (orange) and brooding eggs under flattened segments of limbs (grey circles in 2 & 6).

Barnacles (Cirripedia)

The barnacles illustrated here are representative of two particular orders the stalked barnacles; Pedunculata (1 & 2) and the sessile barnacles; Sessilia (7 & 10).  Also shown are various developmental stages including nauplier larva (3 & 8), cyprinid larva (5 & 6), intermediate forms between the two aforementioned larval stages (4 &9) and post settlement juveniles (11 & 12).  Both order’s shells are comprised of carina (Ca), tergum (Te) and rostrum (R).  Barnacles feed by filtering particulate matter from the water column with their jointed appendages (not labelled).  Female reproductive organs, ovaries (Ov) are found near the base of the animal while the male penis (P) is associated with the testes (H) near the base of the feeding appedages.  The digestive system is coloured yellow.

Centipedes, Millipedes and Relatives (Myriapoda)

The Myriapoda are a subphylum of Arthropods that comprises centipedes (Chilopoda: 1), millipedes (Diplopoda) and similarly structured sister Classes (Pauropoda: 12 & Symphyla: 11).  Centipedes are mostly carnivorous and characterised by having venomous claws (4) as their first set of paired appendages.  The metameric segmentation (repeated segments) of centipedes allows flexibility in the number of walking legs (one pair per segment) between species, however segments with walking legs always come in pairs hence the number of walking legs is only ever in multiples of four.  The Symphyla are also known as pseudocentipedes and are much smaller, lack pigment and eyes, all of which suits their mostly subterrainean lifestyle living in pore spaces of soil eating decaying matter and root hairs.  The Pauropoda are smaller still and, when seen, are found normally found in leaf litter.  This chart illustrates the ganglia associated with each segment and its pair of walking legs (1: blue), male and female reproductive structures of the Chilopoda (6 & 7 respectively) and the initial development from an egg (8-10).

Potato Beetle (Leptinotarsa decemlineata; Coleoptera)

The order with the most numerous species, the coleoptera make up about 40% of all insect species.  Known commonly as beetles their body plan doesn’t vary drastically within the order however homologous structures are often put to different uses.  This chart shows the development (1) of the potato beetle (Leptinotarsa decemlineata) from eggs (a) through the four instars of larvae (b I-IV) and the inactive pre-pupal larva (bV) before skipping the pupal stage to show the adult form (c).  The pre-pupa (2), pupa(3 & 4) and adult (5) are also shown enlarged.  Sketches of an antennae (6), leg (7) and mouthparts (8) are also illustrated.


The stomatopoda are  group of crustaceans called mantis shrimp although they are distinct from shrimp and named mantis for their shared appearance with terrestrial mantids.  They are predatory animals which often ambush from burrow or, less often, actively track and hunt prey.  Prey capture uses very fast moving front appendages typically shaped into a barbed spear or a blunt club, the latter of which can create shock waves similar in nature to those produced by snapping shrimp.  This chart shows the external (1) and internal (2) features of an adult.  The colours represent different systems including the circulartory (red), reproductive (green) and digestive (yellow).  Larval stages are also shown (5-7) which may remain pelagic for up to three months.

Orb Weaver Spider

Anatomy of the orb-weaver spiders where structures of the open circulatory system are in red, alimentary canal in yellow, silk glands in light blue and poison glands in aqua green. The entire animal, longitudinal section is of a female (1) showing the ovary (Ov).  The male testes (T) and vas deferens (V.df) are pictured dissected out (14).  Note the pocketing of the alimentary canal creating the digestive diverticular (Cl1,2,3,4) viewed laterally (1) and dorsally (11).  Other diagrams show various anterior appendages including pinching chelicera (2), pedipalps (3) and various fang shapes (8, 9 & 10).  Other structures represented are the eyes (5), silk glands (6), book lung (12) and developmental stages (15 & 16).

Copepods and Branchiurans

Examples of at least four different genera once grouped together within the order Copepoda.  Now these genera diverge after the class level into too sub classes Branchiura and Copepoda as sister taxa to barnacles.  Care must be taken when analysing these Subclasses relatedness as the class Maxillopoda may not be a monophyletic group.