Lab 8 Flashcards
Ontogeny
The foot and digestive tract undergo torsion, to staying 90°-180°
Gastropoda
Canbrian - recent Marine, fresh, terrestrial Single shell, helical Lost in slugs Digestion right above foot Herbivores Whorl on shell is 360°
Patellogastropoda
Triassic - recent
Grazing on intertidal rocks
Limpet shell evolved independently
Vetigastropoda
Canbrian - recent
Abalones
Many have a slit or one or many openings for respiration
Many have microstructure of nacre, or mother of pearl
Caenogastropoda
Silurian - recent
Largest group
Many have inhalant siphon, expressed on shell as a simple notch or a long canal
Heteronranchia
Carboniferous - recent Two major groups 1- Opisthobranchia Marine Shell concealed or absent Sea slugs, sea hares 2- Pulmonata Land snails and slugs Mantle cavity is a lung
Bellerophontacea
Cambrian - Triassic
Molluscs that resemble Gastropoda
Planispirally coiled
Bivalves
Cambrian - recent Calcareous shell with dorsal hinge Head and radula lacking Marine and freshwater Foot and mouth are anterior and anus siphon posterior Equal valves
Adductor muscle
Isomyarian- same size
Anisomyarian- one is larger
Monomyarian- one is missing
Pallial line goes across, meet at pallial sinus
Bivalves dentition
Taxodont - small numerous teeth
Heterodont - lateral teeth, Cardinal teeth
Small bivalves
Nucloida
Solemyoidea
Nuculanoidea
Pteriomorphia
Oysters and such
Many have byssus
Heteroconchia
Heterodont teeth
Most modern bivalves
