FURTHER PHYLOGENETIC CONSIDERATIONS The aschelminths are diverse animals. They have common cuticle, pseudocoelom, muscular pharynx and adhesive glands. But no distinctive features in every phylum. 1. Origin of Rotifers The…
PHYLUM PRIAPULIDA (priapos, phallus, Creek god of reproduction symbolized by the penis) 1. Habitat: The priapulids are a small group. It has only 16 species of marine worms found in…
PHYLUM LORICIFERA (Lorica, clothed in armor + ferro, to bear) The phylum Loricifera is a recently described animal phylum. Zoologists have described !about 14 species of Loriciferans. Its first members…
PHYLUM ACANTHOCEPHALA (akantha, spine + kephale, head) 1.Habitat: Adult acanthocephalans are endoparasite in the intestinal tract of vertebrates (especially fishes). They complete their life cycle in two hosts. The juveniles…
PHYLUM NEMATOMORPHA(nema, thread + morphe, form) Nematomorphs are a small group of about 250 species. They are elongated worms. They are commonly called horsehair worms or Gordian worms. Habitat: The…
PHYLUM NEMATODA (nemtuos, thread) Nematodes are roundworms. They are some of the most abundant animals on earth. Number or round worm species is from 16, 000 to 500,000. There are…
Phylum Kinorhyncha (kinein, motion + rhynchos snout) Kinorhynchs are small, elongate bilaterally symmetrical worms. Their size is less than 1 mm. They are found exclusively in marine environments. They live…
PHYLUM ROTIFERA (rota, wheel ± (era, to bear) Characteristics of the phylum Rotifera are: 1. The rotifers derive their name from characteristic ciliated organ called corona. Corona is present around…
GENERAL CHARACTERISTICS OF ASCHELIMINTHES Aschelminthes show following characters: 1. They are first invertebrates which posses body cavity. But they lack peritoneal linings and mesenteries. These structures are found in more…
THE PSEUDOCOELOMATE BODY : ASCHELMINTHE EVOLUTIONARY PERSPECTIVE (askos, bladder + helmins, worm) The group Aschelminthes has seven different phyla. They are very diverse animals. They have unclear phylogenetic affinities very…
saadia