Edit the text with your own short phrase. The animation is already done for you; just copy and paste the slide into your existing presentation. Chelsea Miller, Erica Caines, Emma Brown (Group 25)

Edit the text with your own short phrase. The animation is already done for you; just copy and paste the slide into your existing presentation. What Are They? Gastrotrich are divided into two orders which are the Macrodasyida which are all marine, and the Chaetonotidae, some of which are marine and some freshwater MacrodasyidaChaetonotida

Gastrotricha Includes 450 to 700 known species Most are less than 1 mm long, although a few can reach up to 3 mm Their body includes a head, trunk, and sometimes a tail Gastrotricha means “hairy belly” Body is bilaterally symmetrical, and vermiform Body sports various combinations of spines, bristles, and scales or plates

Gastrotricha Possesses a gut with a subterminal anus Has “adhesive tubes” with glands that can be used to attach to objects Contain a nervous system with ganglia Does not contain a circulatory system Adults lack a body cavity

Taxonomic Grouping KingdomAnimalia PhylumGastrotricha ClassGastrotricha OrderMacrodasyidaChaetonotidae

First Order: Macrodasyida Composed of 300 species, which can be broken down into 6 families Live in marine or brackish water Can be distinguished from other gastrotrichs by the presence of two pores on either side of the pharynx Body is dorsally flattened Tubular adhesive glands at both ends of the body/on lateral surfaces Contains cellular epidermis Detritivores and hermaphrodites

Second Order: Chaetonotidae Largest family of gastrotrichs with almost 400 species Marine and freshwater Classification is based on shape/external structures Tenpin or bottle-like shape covered with a thick layer of soft cuticle Do not have pores in the pharynx Pathenogenetic

Diet Gastrotrichs are small marine flatworms that feed on other small organisms and/or materials such as: Bacteria Protists (like small molds, amoeba, and plankton) Fungi Blue or green algae Unicellular algae Debris or waste (they also decompose dead matter)

Edit the text with your own short phrase. The animation is already done for you; just copy and paste the slide into your existing presentation.

Edit the text with your own short phrase. The animation is already done for you; just copy and paste the slide into your existing presentation. Reproduction Since there are two types of Gastrotricha. Those who are from Marine environments, and those who are from Fresh water & marine environments. They both have different mating techniques!

Edit the text with your own short phrase. The animation is already done for you; just copy and paste the slide into your existing presentation. Reproduction The Marine species are mainly hermaphrodites which means they do not have genders, so they have both male and female reproductive organs and transfer sperm into one another by a spermatophore. There is no larval stage; they reach maturity in 2-3 days

Edit the text with your own short phrase. The animation is already done for you; just copy and paste the slide into your existing presentation. Reproduction The Fresh Water Gastrotricha are predominantly pathenogenic, which means they are all functionally female and perform asexual reproduction. The produce two types of eggs 1.Eggs that take 1-4 days to hatch 2.Eggs that are more tough and can withstand extreme temperatures, allowing it to exist in unstable environments

Edit the text with your own short phrase. The animation is already done for you; just copy and paste the slide into your existing presentation. Evolution Evolutionary data is poor for gastrotrichs due to the difficulty in collecting and studying these microscopic soft bodied species It is believed that the most primitive forms are possibly marine The muscular system provides most data for evolution

Edit the text with your own short phrase. The animation is already done for you; just copy and paste the slide into your existing presentation. Evolution Gastrotricha has a distinct evolutionary line from nemotoda, but is suggested to be sister groups due to muscles Monophyly, or clade, supported by the morphological and molecular analyses of the 18S rRNA sequences Ancestors are believed to be the flatworm, fluke, tapeworm and ribbon worm

Edit the text with your own short phrase. The animation is already done for you; just copy and paste the slide into your existing presentation. Facts Gastrotrichs live in small, marine, brackish, and freshwater environments The population density of Gastrotrichs in freshwater habitats may reach over 150 individuals per 10cm². live on and between particles of sediment or on other submerged surfaces, but a few species are terrestrial and live on land in the film of water surrounding grains of soil The name "gastrotrich" comes from the Greek word for stomach