Arynchobdellida

Arhynchobdellida

Hirudo medicinalis and Macrobdella decora

jawed leeches

Mark E. Siddall & E. M. Burreson *



     ,_______________ Erpobdelliformes 
     |     
     |              
_____|                 
     |                 
     |_______________ Hirudiniformes

Table of Contents

Characteristics of the Group
Sources of Information on the Internet
References

Characteristics of the Arynchobdellida
Apomorphies

nephridia suppressed in genital somites
dorsal and verntral blood vessels absent
pharyngeal folds fused into myognaths
oral velum modified to form paragnaths
myognaths armed (reverses variously)
male bursa is single lobed (reverses within the Erpobdelliforms)

Plesiomorphies (relative to Rhynchobdellida)

pharynx not protrusible
intestine acæcate
cephalic eyespots dorsolateral
muscularization of lateral coelomic spaces into "blood vessels"

Sources of Information on the Internet

Life History Evolution

Picture Gallery of Leeches

Classification of Leeches

(Discovery Channel Program) - NICE!

Joel's Houdini the Leech, Riverdale School, Portland, OR

Effect of ale, garlic, and soured cream on the appetite of leeches

Leech Neurobiology Newsletter

Building a better leech

KAIST BioResource LAB
and information on clotting mechanisms

References

Sawyer, R. T. 1986. Leech biology and behaviour. Oxford University Press, Oxford, UK. 10065 pp.

Siddall, M. E., and Burreson, E. M. 1995. Phylogeny of the Euhirudinea: Independent evolution of blood feeding by leeches? Canadian Journal of Zoology, 73: 1048-1064

About This Page
Mark E. Siddall & Gene M. Burreson
Email: mes@vims.edu or gene@vims.edu
Virginia Institute of Marine Science
School of Marine Science
College of William and Mary
Gloucester Point, Virginia 23062, USA
Page copyright © 1995 Mark E. Siddall
Last modified 30 April, 1996