- Title Pages
- Preface to third edition
- Preface to second edition
- Preface to first edition
- 1 Introduction
- 2 ANIMALIA (METAZOA)
- 3 Prelude: Phylum Choanoflagellata
- 4 Early animal radiation
- 5 Phylum Silicea
- 6 EURADICULATA
- 7 <i>Phylum</i> Calcarea
- 8 PROEPITHELIOZOA
- 9 <i>Phylum</i> Homoscleromorpha
- 10 EUMETAZOA (GASTRAEOZOA)
- 11 <i>Phylum</i> Placozoa
- 12 NEURALIA
- 13 <i>Phylum</i> Cnidaria
- 14 TRIPLOBLASTICA
- 15 Phylum Ctenophora
- 16 BILATERIA
- 17 ACOELOMORPHA
- 18 Phylum Acoela
- 19 Phylum Nemertodermatid
- 20 <i>Phylum</i> Xenoturbellida
- 21 EUBILATERIA
- 22 PROTOSTOMIA
- 23 SPIRALIA (LOPHOTROCHOZOA)
- 24 SCHIZOCOELIA
- 25 Phylum Annelida
- 26 <i>Phylum</i> Sipuncul
- 27 Phylum Mollusca
- 28 <i>Phylum</i> Nemertin
- 29 <i>Phylum</i> Platyhelminthes
- 30 Phylum Gastrotricha
- 31 GNATHIFERA
- 32 <i>Phylum</i> Gnathostomulida
- 33 <i>Phylum</i> Micrognathozoa
- 34 <i>Phylum</i> Rotifera
- 35 POLYZOA (BRYOZOA s.l.)
- 36 Phylum Entoprocta
- 37 <i>Phylum</i> Cycliophora
- 38 Phylum Bryozo (Ectoprocta)
- 39 BRACHIOZOA
- 40 <i>Phylum</i> Phoronida
- 41 <i>Phylum</i> Brachiopoda
- 42 ECDYSOZOA
- 43 PANARTHROPODA
- 44 <i>Phylum</i> Arthropoda
- 45 <i>Phylum</i> Onychophora
- 46 <i>Phylum</i> Tardigrada
- 47 CYCLONEURALIA
- 48 NEMATOIDEA
- 49 <i>Phylum</i> Nematoda
- 50 <i>Phylum</i> Nematomorpha
- 51 SCALIDOPHORA
- 52 <i>Phylum</i> Priapul
- 53 <i>Phylum</i> Kinorhynch
- 54 <i>Phylum</i> Loricifera
- 55 <i>Phylum</i> Chaetognatha
- 56 DEUTEROSTOMIA
- 57 AMBULACRARIA
- 58 <i>Phylum</i> Echinodermata
- 59 HEMICHORDATA
- 60 <i>Phylum</i> Enteropneusta
- 61 <i>Phylum</i> Pterobranchia
- 62 CHORDATA
- 63 <i>Phylum</i> Cephalochordata
- 64 <i>Phylum</i> Urochordata
- 65 <i>Phylum</i> Vertebrata (Craniata)
- 66 Problematica
- Systematic index
- Subject index
- Plates
PROTOSTOMIA
PROTOSTOMIA
- Chapter:
- (p.87) 22 PROTOSTOMIA
- Source:
- Animal Evolution
- Author(s):
Claus Nielsen
- Publisher:
- Oxford University Press
The Protostomia is a large clade of bilateral animals that are divided into Spiralia (Lophotrochozoa) and Ecdysozoa, based on molecular phylogenies. Previously known as Zygoneura, the group was named Protostomia based on the fate of the blastopore, which should develop into the mouth (rather than the anus, as in the Deuterostomia). Almost every morphological and molecular study points to the protostomes as monophyletic. The Chaetognatha is placed in a trichotomy with Spiralia and Ecdysozoa, with the morphology and ontogeny of its nervous system supporting their protostomian affinities. The origin and evolution of the characteristic trochophora larva and nervous system, along with the complex of the tubular gut, are explained by the trochaea theory.
Keywords: bilateral animals, Protostomia, Spiralia, Ecdysozoa, blastopore, protostomes, Chaetognatha, nervous system, evolution, trochaea theory
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- Title Pages
- Preface to third edition
- Preface to second edition
- Preface to first edition
- 1 Introduction
- 2 ANIMALIA (METAZOA)
- 3 Prelude: Phylum Choanoflagellata
- 4 Early animal radiation
- 5 Phylum Silicea
- 6 EURADICULATA
- 7 <i>Phylum</i> Calcarea
- 8 PROEPITHELIOZOA
- 9 <i>Phylum</i> Homoscleromorpha
- 10 EUMETAZOA (GASTRAEOZOA)
- 11 <i>Phylum</i> Placozoa
- 12 NEURALIA
- 13 <i>Phylum</i> Cnidaria
- 14 TRIPLOBLASTICA
- 15 Phylum Ctenophora
- 16 BILATERIA
- 17 ACOELOMORPHA
- 18 Phylum Acoela
- 19 Phylum Nemertodermatid
- 20 <i>Phylum</i> Xenoturbellida
- 21 EUBILATERIA
- 22 PROTOSTOMIA
- 23 SPIRALIA (LOPHOTROCHOZOA)
- 24 SCHIZOCOELIA
- 25 Phylum Annelida
- 26 <i>Phylum</i> Sipuncul
- 27 Phylum Mollusca
- 28 <i>Phylum</i> Nemertin
- 29 <i>Phylum</i> Platyhelminthes
- 30 Phylum Gastrotricha
- 31 GNATHIFERA
- 32 <i>Phylum</i> Gnathostomulida
- 33 <i>Phylum</i> Micrognathozoa
- 34 <i>Phylum</i> Rotifera
- 35 POLYZOA (BRYOZOA s.l.)
- 36 Phylum Entoprocta
- 37 <i>Phylum</i> Cycliophora
- 38 Phylum Bryozo (Ectoprocta)
- 39 BRACHIOZOA
- 40 <i>Phylum</i> Phoronida
- 41 <i>Phylum</i> Brachiopoda
- 42 ECDYSOZOA
- 43 PANARTHROPODA
- 44 <i>Phylum</i> Arthropoda
- 45 <i>Phylum</i> Onychophora
- 46 <i>Phylum</i> Tardigrada
- 47 CYCLONEURALIA
- 48 NEMATOIDEA
- 49 <i>Phylum</i> Nematoda
- 50 <i>Phylum</i> Nematomorpha
- 51 SCALIDOPHORA
- 52 <i>Phylum</i> Priapul
- 53 <i>Phylum</i> Kinorhynch
- 54 <i>Phylum</i> Loricifera
- 55 <i>Phylum</i> Chaetognatha
- 56 DEUTEROSTOMIA
- 57 AMBULACRARIA
- 58 <i>Phylum</i> Echinodermata
- 59 HEMICHORDATA
- 60 <i>Phylum</i> Enteropneusta
- 61 <i>Phylum</i> Pterobranchia
- 62 CHORDATA
- 63 <i>Phylum</i> Cephalochordata
- 64 <i>Phylum</i> Urochordata
- 65 <i>Phylum</i> Vertebrata (Craniata)
- 66 Problematica
- Systematic index
- Subject index
- Plates