Invertebrates Rachel Reed & Erin Baxter

Importance 95-99% of all species Pollination Recycling Food in many cultures Food webs Maintenance of ecological communities

E.O. Wilson “If human beings were not so impressed by size alone, they would consider an ant more wonderful than a rhinoceros.”

Basics Aquatic vs. Terrestrial – Arboreal, aerial Anatomical Definitions – Hemolymph, exoskeleton, hydrostatic skeleton Reproductive terms – Dioecious, hermaphroditic, parthenogenesis

Considerations in Aquatic Care Marine vs. Freshwater Water quality Substrate, plants Light Water circulation Other species in aquaria Diet

Considerations in Terrestrial Care Safe, sanitary, not crowded Temperature considerations Substrate, plants Water availability & mode of delivery Arboreal species? Air circulation Diet

Ctenophora “Comb Jellies” Marine waters Carnivorous Diet Water requirements dependent on species Most are hermaphroditic Water Flow patterns are important

Phylogeny

Porifera “Sponges” Primarily Marine; sessile Water requirements dependent on species Unique feeding system; tiny pores; water flow necessary Reproduce by both sexual and asexual means

Phylogeny

Cnidaria AnemonesJellyfish Coral Radial symmetry,Hydrostatic skeleton, Dimorphic development Can sting!

Anemones Marine Need excellent water condition Most capture animal prey; zooanthellae Variable but specific temperature requirements dependent upon species Asexual reproduction Interspecific Aggression

Jellyfish Marine Water flow patterns Predators – have stingers! Sexual reproduction Lots of species variability

Coral Marine Water Quality Important! Zooxanthellae; Most capture animal prey Sexual & Asexual Reproduction Can exhibit contact inhibition and interspecific aggression in the tank Hermatypic vs Ahermatypic

Phylogeny

Echinoderms Marine Water quality important- toxicity problems Diet is largely dependent on species Asexual & sexual reproduction dependent on species Water vascular system  locomotion, gripping, feeding

Phylogeny

Sea Squirts Sessile, marine Environmental management based on species Herbivorous diet Sexual or Asexual reproduction 90% of all urochordates

Gastropods Marine & freshwater Sessile and mobile Filter feeders Tank Management Substrate Dioecious or hermaphroditic

Cephalopods Marine Aquatic Varied diet Active hunters Tank Management Dioecious r_berlin_zoo_aquarium_pd600.jpg

Phylogeny

Pogonophora & Vestimentifera Deep sea dwelling worms! Often grouped together

Phylogeny

Annelids Aquatic and terrestrial Varied diet and feeding strategies Environmental requirements dependent upon species Sexual reproduction; dioecious Biomedical & ecological importance

Phylogeny

Rotifers Most freshwater but some marine and terrestrial Omnivores Water Management Parthenogenic or dioecious

Phylogeny

Flatworms (Turbellarians) Mostly Aquatic Varied diet Commensal and parasitic Tank Management Varied reproduction

Nematodes Aquatic & Marine Varied diet Mostly parasitic Environment Management Dieocious or parthenogenic

Phylogeny

Tardigrades Marine, freshwater & terrestrial “Water bears” Cryptobiosis

Phylogeny

Onychophora Tropical, terrestrial Velvet worms or walking worms Prey on smaller arthropods

Phylogeny

Crustaceans Terrestrial and Aquatic Diet dependent on species Tank Management Dieocious Economic importance

Phylogeny

Insects Predominantly terrestrial Varied Diet Environmental Management Reproduction Social Systems Economical & Ecological Importance

Phylogeny

Myriapods Terrestrial Diet dependent on species Well defined environmental requirements Dieocious; some parthenogenic

Myriapods Millipedes Mostly herbivorous Two pairs per body segment Non-aggressive; slow Easy to handle Centipedes Mostly carnivorous One pair of legs per body segment Aggressive; fast! Extremely hard to handle; venomous

Millipedes Substrate: 8-10cm of soil with 3-4cm of leaf litter on top Temperature Humidity Diet: leaf litter, fruits & vegetables Reproduction

Centipedes Soil covered with leaf litter or mulch Temperature Humidity Light Diet: mix of live and dead invertebrates, dead pinky mice, day old chicks, adult mice, etc. Reproduction

Phylogeny

Horseshoe Crabs Marine, Aquatic Captive diet Various habitats Dieocious Limulus amebocyte lysate (LAL) extracted from hemolymph- Pharmaceutical use

Phylogeny SPIDERS!

Arachnids

Scorpions Terrestrial Carnivorous Environment: mostly desert Sexual reproduction

Spiders Aquatic & terrestrial Carnivores Diverse Environments Sexual Reproduction Silk!

Terrestrial Spiders Arboreal vs. Non-arboreal Diet Substrate Temperature & humidity Lighting

Aquatic Spiders Natural environment Diet Water Quality Underwater “air bells”

Silk Made of Amino Acids Very stable Very Strong Genetic Isolation Production Application

Resources Lewbart, Gregory (ed.) Invertebrate Medicine.Blackwell Publishing, Ames, Iowa. Frye, Fredric L Captive Invertebrates. Krieger Publishing Company, Malabar, Florida. Pechenik, Jan A Biology of the Invertebrates. McGraw-Hill. [5 th ed is 2005.]