SYNOPTIC DESCRIPTION OF THE PHYLUM PRIAPULA
| EUKARYA> UNIKONTA> OPISTHOKONTA> ANIMALIA> BILATERIA> PROTOSTOMATA> ECDYSOZOA> SCALIOPHORA> PRIAPULA |
PHYLUM PRIAPULA LINKS
| The following information came from Margulis and Schwartz (1998), Buchsbaum (1938), Barnes (1980), Barnes (1984), Brusca and Brusca (2003), Hickman (1973), Storer and Usinger (1965), Pechenik (2005), and Tudge (2000). |
- I. SYNONYMS: priapulans.
- II. NAME: 16 extant species (14 fossil species)
- III. PHYLUM CHARACTERISTICS:
- A. Structure
- Symmetry: Bilateral
- Body Cavity: Well-defined and large pseudocoelom (some consider this to be a true coelom).
- Body Covering: Three body regions. Anterior barrel-shaped proboscis (text with tooltip) A proboscis is a tube or tubular process that occurs on the head or the anterior of the gut. ; superficially annulate trunk that is covered by warts, spines, etc.; and a tail with one or two appendages. Chitinous cuticle that is shed periodically.
- Support: Hydrostatic skeleton and cuticle.
- Digestive System: Complete food tube with mouth in the proboscis and the anus on the trunk.
- Circulatory System: Absent but coelomic cells contain haemerythrin (text with tooltip) A respiratory pigment (contains iron) used for respiration in many invertebrates. .
- Locomotion: Longitudinal and circular muscles underlie cuticle. Move through sediment and detritus by everting proboscis.
- Excretory System: Protonephridial (text with tooltip) Protonephridia (protonephridium, sing.) are excretory organs that are ciliated tubules. The flame cell lies at the internal terminus ciliated tubule. and partly combined with the reproductive system.
- Nervous System: Anterior nerve ring and ventral nerve cord.
- Endocrine System: None.
- B. Reproduction:
- Reproductive System: Most are dioecious (text with tooltip) Dioecious organisms have separate male and female individuals. . Fertilization external.
- Development: Zygote develops by radial cleavage and leads to loricate larva.
- C Ecology: Marine, benthic (text with tooltip) A benthic (adj.) organism is one that lives in or on the bottom of marine or freshwater environments. carnivores. Feed on priapulids and other marine worms.
- A. Structure
| LITERATURE CITED Barnes, R. D. 1980. Invertebrate Zoology. Saunders College/Holt, Rinehart and Wilson, Philadelphia. Barnes. R. S. K. 1984a. Kingdom Animalia. IN: R. S. K. Barnes, ed. A Synoptic Classification of Living Organisms. Sinauer Associates, Inc., Sunderland, MA. pp. 129-257. Brusca, R. C. and G. J. Brusca. 2003. Invertebrates. Sinauer Associates, Inc. Sunderland, Mass. Buchsbaum, R. 1938. Animals Without Backbones, An Introduction to the Invertebrates. The University of Chicago Press. Chicago. Hickman, C. P. 1973. Biology of the Invertebrates. The C. V. Mosby Company. Saint Louis. Margulis, L. and K. Schwartz. 1998. Five kingdoms, an illustrated guide to the phyla of life on earth. 3rd Edition. W. H. Freeman and Company. New York. Nicholas, W.L. 2001b. The pseudocoelomate Ecdysozoa. In: Anderson, D.T., ed. Invertebrate Zoology. Oxford University Press. Oxford, UK. pp. 98-119. Nielsen, C. 2001. Animal Evolution: Interrelationships of the Living Phyla. 2nd Edition. Oxford University Press. Oxford. Pechenik, J. A. 2005. Biology of the Invertebrates. McGraw-Hill. New York. Schmidt-Rhaesa, A. 1998. Phylogenetic relationships of the Nematomorpha – a discussion of current hypotheses. Zoologischer Anzeiger 236:203-216. Storer, T. I. and R. L. Usinger. 1965. General Zoology. 4th Edition. McGraw-Hill Book Company. New York. Telford, M. J. S. J. Bourlat, A. Economou, D. Papillion, and O. Rota-Stabelli. 2008. The evolution of Ecdysozoa. Phil. Trans. R. Soc. B. 363: 1529-1537. Tudge, C. 2000. The Variety of Life, A Survey and a Celebration of all the Creatures That Have Ever Lived. Oxford University Press. New York. |
| By Jack R. Holt and Carlos A. Iudica. Last revised: 02/03/2013 |
