What is an Invertebrate: 

A Club-tailed Dragonfly (Gomphus vulgatissimus) (Photo by: Steve J. McWilliam)Many members of the general public feel that any 'creepy crawly' is an insect or a bug but very few understand what an invertebrate is and how many different forms there are.

An invertebrate is literally an 'animal without a backbone'. Invertebrates, which includes insects, bugs and many other forms of creepy crawly, do not have bones inside their bodies like humans and other mammals; they have no solid internal structure on which to hang their soft bits. Instead, they have a hard outer shell made of a substance called 'chitin', a brown, hard, organic compound, inside which their soft bits are either hung from pegs and protuberances or else 'slosh around' like beans in a can. This means that instead of lots of blood vessels (arteries, veins and capillaries) to transport oxygen and food to the organs in their bodies most of their organs are awash in a sea of their blood (called haemocele) and consequently their hearts are small and relatively weak as they only need to 'stir' the blood pool rather than 'pump' it around a large body.

Invertebrates, apart from the lack of a backbone, have many differing lifestyles and have evolved body structures to cope with those lifestyles This can range from many hundreds of legs to no legs at all; from being winged to having no wings or having lost wings; from having a shell to not having a shell; from being herbivorous (plant-eating) through being omnivorous (eating plants and animals) to being carnivorous (meat eating) and many other differences as well. 

Different Types of 'Other' Invertebrate:

The invertebrates most often studied are insects; these have six legs and three body parts (head, thorax and abdomen) with the legs always being attached to the thorax. However there are many other forms of invertebrate. For example:

  • Insects:
    • Bees, Wasps, Ants, Ichneumons, and Sawflies - (Hymenoptera)
    • Beetles (e.g. ladybirds, ground beetles, etc.) - (Coleoptera)
    • Flies (e.g. hoverflies, craneflies, robber-flies, horseflies, midges, etc.) - (Diptera)
    • Bugs (e.g. shield-bugs, aphids, frog-hoppers, etc.) - (Heteroptera)
    • Dragonflies and Damselflies - (Odonata)
    • Lacewings, Scorpionflies, Snakeflies and Alder Flies - (Neuroptera)
    • Moths and Butterflies - (Lepidoptera)
    • Earwigs - (Dermaptera)
    • Grasshoppers and Crickets - (Orthoptera)
    • Springtails - (Collembola)
    • Stoneflies - (Plecoptera)
    • Caddis-flies - (Trichoptera)
    • Mayflies - (Ephemeroptera)
    • Book-lice - (Psocoptera)
    • Bristle-tails (e.g. Silverfish) - (Thysanoptera)
    • Fleas - (Siphonaptera)
  • Arachnids:
    • Spiders
    • Mites - (Acari)
    • Pseudo-Scorpions
    • Harvestmen
  • Molluscs:
    • Snails
    • Slugs
    • Bivalves (e.g. mussels)
  • Annelida:
    • Worms (e.g. earthworms)
    • Flatworms (e.g. New Zealand Flatworm)
    • Leeches - (Hirudinae)
  • Crustacea:
    • Woodlice - (Isopoda)
    • Freshwater Shrimps - (Amphipoda)
  • Myriapods:
    • Centipedes - (Chilopoda)
    • Millipedes - (Diplopoda)

The Cockchafer (Melolontha melolontha) - a beetle  (Photo by: Steve J. McWilliam)Many more types of very small invertebrates exist (such as the copepods which swim in ponds and streams) but study of these is beyond the scope of this web-site being more allied to microscopy workers using compound microscopes rather than the stereo microscopes used by entomologists. A great deal of assistance with the study of insects and other invertebrates can be obtained by joining a regional/local entomological group such as the Lancashire and Cheshire Entomological Society (LCES) or a national entomological group such as the British Entomological and Natural History Society and/or the Amateur Entomologists' Society, or by contacting your Local Record Centre (e.g. rECOrd - The Cheshire LRC)

Invertebrates Within Cheshire:

Cheshire as both a Modern (post-1974) Authority structured county including the areas of Halton and Warrington above the River Mersey in what used to be South Lancashire and also as the much larger Watsonian Vice-County (VC-58 - Cheshire) which includes the Wirral and the 'pan-handle' around Stockport and Tameside has examples of all of the above types of invertebrate within its borders. Some of the groups such as the Lepidoptera (Butterflies and Moths), and the Odonata (dragonflies and Damselflies) are very well studied indeed and the distributions and life-cycles of the species within the county are well understood. However, other groups such as the mites (Acari), the worms (Annelida) and the Book-lice (Psocoptera), amongst many others, are very little known at all.

Should you study any group of invertebrates within the Cheshire and South Lancashire areas I would be very pleased to hear from you and to aggregate your observation records to enable us to better understand the distribution and biology of invertebrates within the region. Many thanks for your help.

NEW: Cheshire Moth Group:

Towards the end of 2001 a new Cheshire Moth Group came into formation to progress the recording of all moths within the Cheshire region and to work towards an atlas covering both macros and micros within approximately five years from 2002. Another aspect of this group will be the formation of a Moth Panel to vet records from recorders each year in a similar vein to the panels which have been run by bird-watchers (ornithologists) for the past ten years or so.

Currently the people involved are Adrian Wander, Paul Hill, Steve McWilliam, Steve Hind, Shane Farrell, Eric Kearns, Kevin McCabe, Jeff Clarke and Phil Rees.

For further details please contact Adrian Wander.

  Home   Education   Invertebrates   Computing   Links  

© Consult-Eco - 1998-2002 - All rights reserved
4 Priory Close, Halton, Runcorn, Cheshire, WA7 2BN
Tel: 01928-573697
WebMaster:  Steve J. McWilliam
Rev. 1.3    Change-Date: 04/01/2002
For assistance with Entomology, Education, Invertebrates, Surveying, Local Record Centres or Web Design/Construction
please contact Steve J. McWilliam  at Consult-Eco:- stevemc@consult-eco.ndirect.co.uk