Invertebrates

The invertebrates are characterized as animals that lack a backbone.The invertebrates are characterized as animals that lack a backbone.

Only the groups for which I have good quality photos are represented in these galleries. There are many other extant invertebrate phylums, but these groups are mostly marine, microscopic or internal parasites and so are unlikely to ever appear on these pages.

Phylum: Arthropoda

The largest Phylum on Earth with well over 1 million species described. Most of these are insects, but the phylum also includes spiders, mites, ticks, crabs, etc.  Arthropods are characterized by having a jointed exoskeleton with segmented abdomen and segmented legs.

Phylum: Mollusca

Soft-bodied invertebrates which are mostly aquatic but with numerous terrestrial species found among the snails and slugs. Approximately 50000 known species worldwide.

 

Phylum: Cnidaria

Simple, generally soft-bodied and mostly marine species. May be free-swimming medusa, anchored polyps or both. Approximately 9400 known species worldwide.