TABLE 4.1Estimates of Mean Number of Parasite Species per Host, Mean Host Specificity, and Global Species Richness for the Parasitic Trematodes, Cestodes, Nematodes, and Acanthocephalans That Parasitize Each of the Major Vertebrate Taxa of Hosts [after Poulin and Morand, 2004)]

Parasite SpeciesHost Species (known no. of host species)
Chondrichthys (843)Osteichthys (18,150)Amphibia (4,975)Reptilia (6,300)Aves (9,040)Mammalia (4,637)Total (43,945)
Mean parasite species per host species
Trematoda0.122.041.271.063.241.61
Cestoda2.711.570.270.393.671.89
Acanthocephala—1.010.190.420.720.28
Nematoda0.481.492.822.153.323.90
Mean host specificity
Trematoda2.006.355.401.772.972.01
Cestoda1.696.384.752.212.361.89
Acanthocephala—14.956.7412.508.354.32
Nematoda2.6710.285.272.123.286.07
Estimated global species richness
Trematoda515,8311,1703,7739,8623,71424,401
Cestoda1,3524,4662831,11214,0584,63725,908
Acanthocephala—1,2261402127793012,658
Nematoda1522,6312,6626,3899,1502,97923,963
Total1,55514,1544,22511,48633,84911,63176,930

From: 4, Homage to Linnaeus: How Many Parasites? How Many Hosts?

Cover of In the Light of Evolution
In the Light of Evolution: Volume II: Biodiversity and Extinction.
National Research Council (US); Avise JC, Hubbell SP, Ayala FJ, editors.
Washington (DC): National Academies Press (US); 2008.
Copyright 2008 by the National Academy of Sciences. All rights reserved.

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.