What does the word Ecdysozoa mean?

What does the word Ecdysozoa mean?

Filters. A taxonomic clade within the clade Protostomia — animals that shed their exoskeleton (ecdysis). pronoun.

What is the clade Ecdysozoa?

Ecdysozoa is a clade composed of eight phyla: the arthropods, tardigrades and onychophorans that share segmentation and appendages and the nematodes, nematomorphs, priapulids, kinorhynchs and loriciferans, which are worms with an anterior proboscis or introvert.

What is the difference between Ecdysozoa and Lophotrochozoa?

Ecdysozoans have the ability to shed their exoskeleton several times throughout their life span, whereas lophotrochozoan are the animals who possess a trochophore larvae and a feeding structure called lophophore.

What makes an Ecdysozoan an Ecdysozoan?

Ecdysozoans are a morphologically heterogeneous group of animals which have a cuticle and grow by molting and include the arthropods and nematodes.

Are sea stars ecdysozoa?

SUBPHYLUM Asterozoa (free-moving echinoderms with flattened, star-shaped bodies): CLASS Asteroidea (sea stars, also called starfish) These familiar sea creatures are predators that move about with five radial arms. The arms touch one another at their base of attachment to the central disk.

Does a flatworm molt?

The name comes from the word ecdysis, which refers to the periodic shedding, or molting, of the exoskeleton. The ecdysozoan phyla have a hard cuticle covering their bodies that must be periodically shed and replaced for them to increase in size.

Are flatworms Ecdysozoa?

The flatworms are acoelomate organisms that include free-living and parasitic forms. The nematodes, or roundworms, possess a pseudocoelom and consist of both free-living and parasitic forms. The nematodes and the arthropods belong to a clade with a common ancestor, called Ecdysozoa.

Are octopus Lophotrochozoans?

The Trochozoa contain many worm-like forms, including the segmented worms (Phylum Annelida) but it also includes the Mollusca (snails, squid, octopods, clams, etc).

What are the main members of the Ecdysozoa?

The Ecdysozoa include the following phyla: Arthropoda, Onychophora, Tardigrada, Kinorhyncha, Priapulida, Loricifera, Nematoda, and Nematomorpha. A few other groups, such as the gastrotrichs, have been considered possible members but lack the main characters of the group, and are now placed elsewhere.

Are earthworms Lophotrochozoa?

Protostome Evolution The Lophotrochozoa – which includes the segmented worms, molluscs, lophophorates and several smaller phyla.

What is the key characteristic of the Ecdysozoa?

Characteristics. The most notable characteristic shared by ecdysozoans is a three-layered cuticle (four in Tardigrada) composed of organic material, which is periodically molted as the animal grows. This process of molting is called ecdysis, and gives the group its name.

Is a sea star an Ecdysozoan?

What is Ecdysozoa in biology?

Ecdysozoa ( /ˌɛkdɪsoʊˈzoʊə/) is a group of protostome animals, including Arthropoda ( insects, chelicerata, crustaceans, and myriapods ), Nematoda, and several smaller phyla. They were first defined by Aguinaldo et al. in 1997, based mainly on phylogenetic trees constructed using 18S ribosomal RNA genes.

Are roundworms part of the Ecdysozoa?

Inclusion of the roundworms within the Ecdysozoa was initially contested but since 2003, a broad consensus has formed supporting the Ecdysozoa and in 2011 the Darwin–Wallace Medal was awarded to James Lake for the discovery of the New Animal Phylogeny consisting of the Ecdysozoa, the Lophotrochozoa, and the Deuterostomia.

Is Ecdysozoa Panarthropoda or Cycloneuralia?

The non-panarthropod members of Ecdysozoa have been grouped as Cycloneuralia but they are more usually considered paraphyletic in as representing the primitive condition from which the Panarthropoda evolved. A modern consensus phylogenetic tree for the protostomes is shown below.

Are Ecdysozoa polyphyletic or Annelida?

The grouping proposed by Aguinaldo et al. is almost universally accepted, replacing an older hypothesis that Panarthropoda should be classified with Annelida in a group called the Articulata, and that Ecdysozoa are polyphyletic.