Phylum Mollusca 1 10:29 AM Lophotrochozoa Either presence of a U shaped gut and lophophore or Trochophore larval stage Porifera Placozoa Cnidaria Ctenophora Platyhelminthes Gastrotricha Gnathostomulida Cycliophora Rotifera Annelida Mollusca Sipuncula Nemertea Brachiopoda Phoronida Bryozoa Arthropoda Tardigrada Onychophora Nematomorpha Nematoda Priapulida Kinorhyncha Loricifera Echinodermata Hemichordata Chordata Trochozoans Trochophore larva Porifera Placozoa Cnidaria Ctenophora Platyhelminthes Gastrotricha Gnathostomulida Cycliophora Rotifera Annelida Mollusca Sipuncula Nemertea Brachiopoda Phoronida Bryozoa Arthropoda Tardigrada Onychophora Nematomorpha Nematoda Priapulida Kinorhyncha Loricifera Echinodermata Hemichordata Chordata Page 1
Trochophore larva Apical tuft Stomach Ciliary band Mouth Anus 4 Animal innovations (apomorphies) 1. Schizocoel, and metanephridia filtering coelomic fluid 2. Dorsal heart and pericardial cavity 1 2 Porifera Placozoa Cnidaria Ctenophora Platyhelminthes Gastrotricha Gnathostomulida Cycliophora Rotifera Annelida Mollusca Sipuncula Nemertea Brachiopoda Phoronida Bryozoa Arthropoda Tardigrada Onychophora Nematomorpha Nematoda Priapulida Kinorhyncha Loricifera Echinodermata Hemichordata Chordata Schizocoelous coelom Ectoderm Endoderm Mesoderm 6 Page 2
Metanepridia Nephrostome Tubule Cilia Bladder Nephridiopore 7 Mollusca Radula Dorsal mantle Calcerous spicules or shells Ventral ciliated muscular foot Retractor muscles Tetraneural nervous system Porifera Placozoa Cnidaria Ctenophora Platyhelminthes Gastrotricha Gnathostomulida Cycliophora Rotifera Annelida Mollusca Sipuncula Nemertea Brachiopoda Phoronida Bryozoa Arthropoda Tardigrada Onychophora Nematomorpha Nematoda Priapulida Kinorhyncha Loricifera Echinodermata Hemichordata Chordata Extant Animalia ~1,300,000 species Parazoa (1.2%) Radiata (0.9%) Protostomia (3.9%) Platyzoa (2.2%) Platyhelminthes (1.9%) Others (0.3%) Lophotrochozoa (9.8%) Mollusca (8.5%) Annelida (0.9%) Others (0.5%) Ecdysozoa (82.0%) Crustecea (3.1%) Chelicerata (7.6%) Tracheata (70.3%) Others (1.1%) Deuterostomia (4.0%) Chordata (3.5%) Others (0.4%) 9 Page 3
Mollusc diversity (Adaptive radiation) 10 Mollusc diversity (Adaptive radiation) 11 Mollusc diversity (Adaptive radiation) 12 Page 4
Mollusc diversity (Adaptive radiation) 13 Mollusc diversity (Adaptive radiation) 14 Mollusc diversity (Adaptive radiation) 15 Page 5
Mollusc diversity (Adaptive radiation) 16 Mollusc diversity (Adaptive radiation) 17 H.A.M. Hypothetical aggregate ancestor Pericardial cavity Gonad Radula Metanephridium Mantle cavity Ctenidium Stomach and digestive gland Foot 18 Page 6
Radula 19 Radula Odontophore Radular teeth 20 Radula Radular muscles Radula Odontophore Odontophore muscles Mouth 21 Page 7
Dorsal mantle covers the visceral mass 22 Secretes the shell 23 Ciliated ventral foot 24 Page 8
Tetraneural nervous system G G G G G G G G G G G G 25 Ctenidium (Respiration) 26 Complete digestive system 27 Page 9
Open circulatory system with a pericardial cavity 28 Pericardial cavity Artery Pericardial cavity Heart atrium Heart ventricle Artery Ctenidium Mantle cavity 29 Excretory and reproductive systems Gonad Urogenital duct Urogenital pore Pericardial cavity Metanephridium Mantle cavity Nephridiopore 30 Page 10
H.A.M. Hypothetical aggregate ancestor Pericardial cavity Gonad Radula Metanephridium Mantle cavity Ctenidium Stomach and digestive gland Foot 31 Veliger larva Stomach Digestive cecum Shell Foot Metanephridium Velum Esophagus 32 Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Aplocophora (autapomorphies) Foot inside a ventral pedal groove Copulatory spicules 33 Page 11
Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Symplesiomorphies Shell glands in mantle produce a solid shell Mantle surrounds viscera Digestive glands Rippling of muscular foot Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Polyplacophora (Autapomorphies) Eight shell valves 35 Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Symplesiomorphies Univalve shell Periostracum, prismatic and nacreous shell layers Mantle margin trilobed Crystalline style Page 12
Mollusc shell Periostracum Prismatic layer Nacreous layer Mantle epithelium Mantle lobes 37 Pearl formation Periostracum Prismatic layer Nacreous layer Developing pearl Epithelium 38 Mollusc stomach Digestive glands Gastric shield Crystalline style Esophagus Style sac Ciliated sorting area Intestine 39 Page 13
Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Monoplacophora (Autapomorphies) Multiple paired structures 40 Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Symplesiomorphies Visceral mass elongated on dorsal-ventral axis Coiled shell Well defined head Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Gastropoda (Autapomorphies) Torsion Concentration of visceral mass Assymetric body plan Page 14
Torsion Anus Velum Mouth Foot 43 Torsion Mouth Heart Anus Ctenidium Mantle cavity Mouth Mantle cavity Ctenidium Anus Heart 44 Snail Shell Anus Foot Pneumostome Tentacle (Eye stalks) Tentacle Mouth Genital pore 45 Page 15
Snail - Digestion Digestive gland Intestine Anus Crop Salivary gland Mouth 46 Snail - Reproduction Ovotestis Hermaphroditic duct Seminal receptacle Albumin gland Combined sperm duct & oviduct Mucus gland Dart sac Penis Vagina Genital pore 47 Terrestrial 48 Page 16
Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Cephalopoda (Autapomorphies) Closed circulatory system Ink sac Modifications of the foot Beak-like jaw Cartilaginous brain case Adaptations as predators 50 Squid Tentacle Arm Funnel (siphon) Collar Eye Fin 51 Page 17
Squid gas exchange Shell (Pen) Funnel Systemic heart Branchial heart Ctenidium 52 Squid digestion Radula Salivary gland Digestive gland (liver) Jaw Anus Ink sac Intestine Pancreas Stomach Cecum 53 Male squid Penis Testis Hectocotylous arm 54 Page 18
Female squid Ovary with eggs Oviducal gland Nidamental glands Oviducal opening 55 Colour production Elastic capsule chromatophores Iridiocytes Bioluminescence Squid camouflage1 Squid camouflage2 56 Squid eye Iris Retina Optic nerves Lens Cornea 57 Page 19
Squid nervous system Nerves to the posterior Eye ball Optic lobe Statocyst Subesophageal complex Supraesophageal complex Esophagus Brachial nerves to the arms 58 Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Symplesiomorphies Modifications for a sedentary life Digging foot Mantle and shell surrounds entire body Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Scaphopoda (Autapomorphies) Mantle closed on ventral side forming a tusk-like shell 60 Page 20
Mollusc Phylogeny Polyplacophora Gastropoda Scaphopoda Aplacophora Monoplacophora Cephalopoda Bivalvia Bivalvia (Autapomorphies) Loss of radula Lateral compression of the body Ctenidia and mantle cavity specialized for filter feeding H.A.M. Hypothetical aggregate ancestor Pericardial cavity Gonad Radula Metanephridium Mantle cavity Ctenidium Stomach and digestive gland Foot 62 Bivalve structures Labial palp Anterior shell adductor Foot Hinge Ctenidium Posterior shell adductor Excurrent siphon Incurrent siphon 63 Page 21
Clam anatomy Metanephridium Pericardial cavity Heart Intestine Stomach Excurrent Incurrent Intestine Gonad 64 Clam anatomy Digestive gland Stomach Excurrent Incurrent Intestine Gonad 65 Clam anatomy Pericardial cavity Heart Intestine Excurrent Incurrent 66 Page 22
Clam anatomy Metanephridium Pericardial cavity Heart Intestine Excurrent Incurrent Gonad 67 Circulatory system Artery Pericardial cavity Heart Atrium Artery Foot Ctenidium 68 Clam ctenidia Interlamellar junctions Ostium Frontal cilia Exhalent water Blood vessel 69 Page 23
Locomotion 70 Freshwater clam Glochidia 71 Page 24