CHART II: ANIMAL KINGDOM
Divisions
Estimated
Number
of Species
d
Taxonomic Classifications
>
Protozoa
(acellular animals)
Mesozoa
Porifera
(sponges)
Coelenterata
(coelenterates)
Ctenophora
(comb jellies)
Platyhelminthes
(flat worms)
Nemertinea
(nemertine worms)
Aschelminthes
a
\
Acanthocephala
3 J
Entoprocta
b
Ectöprocta
b
(moss animals))
Phoronida
Brachiopoda
(lamp shells)
Mollusca
(mollusks)
Sipunculoidea
Annelida
0
(segmented worms)
Arthropoda
(arthropods)
Chaetognatha
(arrow worms)
Echinodermata
(echinoderms)
Hemichordata
Chordata
(including
vertebrates)
15,000
5,000
10,000
100
6,000|
>Acoelomates
500 (
7,ΟΟθ|
/•Pseudocoelomates
>Radiata
3,000
->
15
120
70,000
J
^Protostomia/
^Schizocoela
• Bilateria
6,500 >Eucoelomates\
750,0001
30
1
5,000
60,000
fEnterocoela>Deuterostornia|
a Includes Rotifera, Gastrotricha, Kinorhyncha, Nematoda, Nematomorpha, Priapuloidea. Formerly called Nemathelminthes.
b Formerly in Bryozoa.
c Includes Echiuroidea.
d Taken from "Händbook of Biological Data" (4), p. 533.
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