Are the molluscs lophotrochozoans and Ecdysozoans?

Are the molluscs lophotrochozoans and Ecdysozoans?

Lophotrochozoa is a monophyletic group of animals that includes annelids, molluscs, bryozoans, brachiopods, platyhelminthes, and other animals that descended from the common ancestor of these organisms. Lophotrochozoa is one of the three major clades that comprise bilateral animals, or Bilateria.

Are crustaceans lophotrochozoans?

Most arthropods (insects, crustaceans, myriapods, and chelicerates, belonging to the superphylum of Ecdysozoa) and some species of mollusks and annelids (superphylum Lophotrochozoa) have between 2 and 27 Toll genes.

What traits distinguish the lophotrochozoans?

Characteristics. The clade Lophotrochozoa is named after the two distinct characteristics of its members; the feeding structure lophophore, which is a ciliated crown of tentacles surrounding a mouth, and the developmental stage trochophore larvae.

What separates Ecdysozoans from other invertebrates?

The most distinguishing and prominent feature of Ecdysozoans is their cuticle: a tough, but flexible exoskeleton that protects these animals from water loss, predators, and other aspects of the external environment. All members of this superphylum periodically molt or shed their cuticle as they grow.

Do platyhelminthes have a lophophore?

Phylum Platyhelminthes. The flatworms possess neither a lophophore nor trochophore larvae, although the larvae of one group of flatworms, the Polycladida (named after its many-branched digestive tract), are considered to be homologous to trochophore larvae.

Do all lophotrochozoans have a lophophore?

As lophotrochozoans, the organisms in this superphylum possess either lophophore or trochophore larvae. The exact relationships between the different phyla are not entirely certain. The lophophores include groups that are united by the presence of the lophophore, a set of ciliated tentacles surrounding the mouth.

What defines ecdysozoa?

Ecdysozoa (/ˌɛkdɪsoʊˈzoʊə/) is a group of protostome animals, including Arthropoda (insects, chelicerata, crustaceans, and myriapods), Nematoda, and several smaller phyla. strongly supported the Ecdysozoa as a clade, that is, a group consisting of a common ancestor and all its descendants.

Are jellyfish ecdysozoa?

Radiata includes Phylums Cndiaria (hydra, jellyfish, boxie jellies sea anemones, coral) and Ctenophora (comb jellies). Ecdysozoa includes Phylums Nematoda (roundworms) and Arthropods (spiders, scorpions, crustaceans, insects, millipedes, centipedes).

Do Nemertea have a lophophore?

The flatworms possess neither a lophophore nor trochophore larvae, although the larvae of one group of flatworms, the Polycladida (named after its many-branched digestive tract), are considered to be homologous to trochophore larvae.

What type of Coelom do platyhelminthes have?

‘ And, as you might have suspected, Platyhelminthes are a phylum of worms that are flat in shape. Well, their shape comes from the fact that they, unlike earthworms, have no coelom (otherwise known as a fluid-filled body cavity). Therefore, Platyhelminthes are acoelomates (‘a’ meaning ‘without’).

What’s the difference between a Lophotrochozoan and an ecdysozoan?

• Unlike the lophotrochozoan, ecdysozoans possess a special steroid hormone called ecdysteroids. • Ecdysozoa include the nematodes, arthropods, onychophorans , and tardigrades, whereas lophotrochozoan include flatworms, nemerteans, mollusks, annelids, lophophorate, and rotifer.

What are the characteristic features of the group Lophotrochozoa?

What is Lophotrochozoa? The characteristic features of the group lophotrochozoa are the presence of a trochophore larvae and a feeding structure called lophophore. However, only few lophotrochozoans possess both of these characteristic features.

How are ecdysozoans different from other animal groups?

The name ecdysozoan is given to this group of animals due to the presence of special steroid hormone called ecdysteroids, which controls the process called ecdysis or metamorphosis. Ecdysozoans possess a cuticular skeleton and are able to shed the skeleton through the ecdysis. Most of the members in this group possess separate sexes.

How did the Lophotrochozoans get their name?

Lophotrochozoans Their name was created from the names of formerly-separated groups that have now been joined in a single clade on the basis of the similarities of their genomes: They all share a cluster of HOX genes quite different from those found in the ecdysozoans (and deuterostomes). They share similar sequences in their 18S rRNA genes.