MOLLUSCA

Belemnites

• Have a distinct W-shaped pupil in bright light that changes to circular in darkness
• Possess a parrot-like beak and long lateral fins for maneuvering at high speeds
• Can alter their color and pattern at any time for camouflage and communication
• Have a large brain to body size ratio

Sepiadariidae (Bottletail Squids)

• Short, 2-4 cm in length
• Benthic, found in bottom sediments of a sea or any body of water
• Have striking color patterns

Cuttlefish

• Can change their colors due to chromatophores
• Camouflage for communication and protection
• Use their very long tentacles to catch prey, moving very fast

Order Teuthida

• Have a rod-like, chitinous gladius (plastic shell)
• Possess chromatophores for color change
• Some are bioluminescent
• Have an ink gland to evade predators

Family Sepiolidae

• Small, 1-10 cm in length, with a broad and rounded posterior mantle
• Have ear-like fins and are benthic or pelagic
• Uroteuthis sp. produces a spermatophore, common in complex chambered heart

Mollusks (Part 2)

• Have a complex chambered heart with 3 chambers (2 auricles and 1 ventricle)
• Absence of cilia in gills, used primarily for gaseous exchange
• Gills are used for filter feeding in other mollusks (bivalves and gastropods)
• Have a chitinous beak/radula used to reduce large food
• Chromatophores are pigment cells for camouflage, identification, and communication
• Ink gland is used to evade enemies, not only in squid but also in octopus and cuttlefish

Cephalopods

• Have big and mobile eyes
• Can retract their tentacles to specialized pouches in the head region
• Use their tentacles to capture prey, aiming and rapidly shooting them

Subclass Pulmonata

• Body is projectile- or sac-shaped
• Shells are orthoconic, cyrtoconic, or rarely coiled
• Possess highly developed eyes
• Left fourth arm serves as hetocotylus
• Have denticulated suckers surrounding the mouth