What are lophotrochozoans and ecdysozoans?
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. • Unlike the lophotrochozoan, ecdysozoans possess a special steroid hormone called ecdysteroids.
Are Lophophores homologous?
Thus, the lophophore is a homologous structure, which was inherited by all lophophorates from the last common ancestor. Despite the significant morphological similarity, the lophophorates monophyly is not supported by the latest molecular phylogenetic data.
What are the characteristics of lophotrochozoans?
The lophotrochozoans are triploblastic and possess an embryonic mesoderm sandwiched between the ectoderm and endoderm found in the diploblastic cnidarians. These phyla are also bilaterally symmetrical, meaning that a longitudinal section will divide them into right and left sides that are symmetrical.
Are Lophophores analogous or homologous?
All species in these phyla have a lophophore, which is regarded as a homologous structure of the lophophorates.
Which animals are lophotrochozoans?
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 earthworms lophotrochozoans?
Protostome Evolution The Lophotrochozoa – which includes the segmented worms, molluscs, lophophorates and several smaller phyla.
Are Lophophores ancestral or derived?
Morphologically, the grouping seems logical and simple enough. The lophophore is a highly derived, specialized feeding structure that is unlikely to have evolved more than once.
Which of the following are characteristics of bryozoans?
Characteristics of Bryozoa:
- Bilaterally symmetrical.
- Body has more than two cell layers, tissues and organs.
- Body cavity a true coelom.
- Body possesses a U-shaped gut with an anus.
- Body enclosed in a calcareous, chitinous or gelatinous box, tube or communal matrix.
Which two groups of animals make up the lophotrochozoans?
The name Lophotrochozoa comes from the names of the two major animal groups included: the Lophophorata and the Trochozoa.
Who proposed Lophophorate theory?
Garstang
(A) Theory 1 was first proposed by Garstang (1928), and espouses the notion that the nonfeeding ascidian tadpole larva evolved from echinoderm-like and hemichordate-like larvae.
Do all brachiopods have Lophophores?
Brachiopods have a characteristic morphology with peduncle, lophophore, and two valves. Most are sessile epifaunal suspension-feeders. Brachiopod have an extensive traditional taxonomy.
How many lophotrochozoans are there?
Abstract. Molluscs are protostomes belonging to the Lophotrochozoa superphylum and are the second most diverse animal phylum, after arthropoda, regrouping about 93 000 species.
What is a lophophorate?
Simply put, a lophophorate is any organism that bears a lophophore. This is a pair of spiral feeding structures that form a crown on the head superficially similar to the feeding tentacles of feather-duster worms.
Are lophophorates protostome animals?
Halanych KM, Bacheller JD, Aguinaldo AMA, Liva SM, Hillis DM, & Lake JA (1995) Evidence from 18S Ribosomal DNA that the lophophorates are protostome animals. Science 267: 1641-1643.
What are some examples of lophophores?
Traditionally the lophophorates include the brachiopods or lampshells, the bryozoans or moss-animals, and the phoronids as well as the entoprocts which do not have a true lophophore but are otherwise very similar to bryozoans.
What is the function of lophophore in fish?
lophophorate, any of three phyla of aquatic invertebrate animals that possess a lophophore, a fan of ciliated tentacles around the mouth. Movements of the cilia create currents of water that carry food particles toward the mouth.