Are Chaetognatha Triploblastic?

Are Chaetognatha Triploblastic?

Triploblastic relationships with emphasis on the acoelomates and the position of Gnathostomulida, Cycliophora, Plathelminthes, and Chaetognatha: a combined approach of 18S rDNA sequences and morphology.

Are Chaetognatha Protostome or Deuterostome?

This gene is present in cnidarians and deuterostomes, but lost in protostomes, suggesting that chaetognaths are a stem protostome group (Supplemental data).

What are the process of reproduction in Chaetognatha?

Reproduction in chaetognaths is unique. All chaetognaths are hermaphroditic, meaning they have both male and female parts. Eggs are formed in the trunk region of the body, whereas the sperm develop in the tail portion. Sperm can sometimes be seen swimming inside the tail portion of the body.

Is Chaetognatha a phytoplankton or zooplankton?

The Chaetognatha /kiːˈtɒɡnəθə/ or chaetognaths /ˈkiːtɒɡnæθs/ (meaning bristle-jaws) are a phylum of predatory marine worms that are a major component of plankton worldwide.

Are copepods Holoplankton?

Learn about zooplankton, such as copepods, rotifers, tintinnids, and larvaceans, that are examples of permanent plankton (holoplankton). Crustaceans are the most important members of the zooplankton.

What do arrow worms do?

Arrow worms are long, straight, narrow sea worms that use hooks for catching prey. Arrow worms that live near the surface are clear, which helps them avoid predators.

Are Chaetognatha deuterostomes?

Chaetognaths have generally been considered close relatives of the deuterostomes, a long-established major animal group that includes chordates, such as humans, and echinoderms, such as sea urchins.

What does the name Chaetognatha mean?

Chaetognatha, meaning bristle-jaws, and commonly known as arrow worms, are a phylum of predatory marine worms that are a major component of plankton worldwide. About 20% of the known species are benthic, and can attach to algae and rocks. There are more than 120 modern species assigned to over 20 genera.

Is jellyfish a Meroplankton or Holoplankton?

Jellyfish are the largest example of holoplankton. They remain in the planktonic zone for life and can grow as large as 8 feet, with tentacles up to 200 feet. Meroplankton are eggs and larvae of nearly all species of fish and benthic invertebrates.

Are fish larvae Holoplankton or Meroplankton?

Almost all invertebrates and fishes have planktonic larvae which are effectively dispersed to new habitats by the currents. Not only holoplankton, such as the copepods, but also the meroplanktonic fish larvae and various micronekton do migrate vertically (Arinardi et al., 1990, Schalck et al., 1990).