102(Lab)_2nd Long Exam

Skeletal System of Bonyfish

1. Ethmoid

2. Orbital

3. Otic

4. Basicranial

4 Regions of Nuerocranum

most anterior dorsal skull bone

Ethmoid

 supports the nose and helps in smelling

Ethmoid_f

supports smell structures; separate nasal passages; part of nasal cavity

Lateral ethmoid

forms lower part of nasal septum

Vomer

 lateral to the ethmoid region; supports bridge of the nose

Nasals

 supports the eyes and provides attachment for eye muscles

Orbital

 paired, supports the braincase and eye orbit

Pterosphenoids

from the pterosphenoids down to the parasphenoid (divide the orbit into left and right halves) ; connects brain to skull base

Basisphenoid

protect and support the eyeball

 Sclerotic cartilage or bone

cover most of the dorsal surface of the cranium; protects the brain

Frontals

form a ring around the eyes

Circumorbitals

surrounds the eye pocket: protects front of the eye; supports sensory canals

lachrymal/ pre-orbital

protects lower part of the eye; carries sensory canals

jugal (below the eye)

(below the orbit) protects lower-front part of eye

True sub-orbirtal

protects the back of the eye; connect orbit to the skull

Dermosphenotic bones

five bones enclose each bilateral otic chamber inside the skull

Otic

paired, most posterior dorsolateral part of the orbit roof; protects ear and support hearing structures

Phenotics

(back of skull near otic reagion): protect inner ear: support braincase and connect skull bones

Pterotic

(back of skull near otic reagion): protect inner ear: support braincase and connect skull bones

Prootics

between prootics and other otic bones; stabilizes ear region; connect otic bones

Intercalars/oisthotics

(back of otic region); protects brain near the ear; structural support

Parietals

Basicranial: 3 sets of bones

ventral part of braincase; strengthens skull base; supports jaw muscles

Parasphenoid

Holds front teeth; helps in grabbing food

Pre-maxillae

tooth-bearing bone; helps in biting

Maxillae

Assists maxilla; adds support/flexibility

Supramaxilla

Main tooth-bearing bone of lower jaw; biting/chewing

Dentary

Forms jaw joint; helps in jaw movement

Angular (Articular)

Helps jaw opening/closing (muscle attachment)

Retroarticular

Form part of roof of mouth; help in feeding

Paletines

Support palate; may hold teeth

Ectopterygoids

Form roof of mouth; structural support

Entopterygyoids

Connect bones; help in jaw suspension

Metapterygoids

Main jaw support; connects jaw to skull

Hyomandibula

helps stabilize jaw point

Symplectic

forms hinge; movement

Quadrate

tongue and breathing suppport

Hyoid complex

support front of tongue

Hyophyals (Basihyals)

tongue and gill area

Ceratohyal

supports branchiostegal rays

Epihyal

Connects hyoid to skull/jaw support

Interhyal

Main tongue support

Glossohyal

helps in respiration (gill movement)

Branchiostegal Rays

Gill Cover

Opercular Apparatus

main gill cover; protects gills; helps in breathing

Opercle

Supports opercle; protection

Subopercle

Protects and supports gill cover area

Preopercle

Helps in jaw movement + respiration

Interopercle

Gills and Feeding

Branchial Complex

base support for gill arches

Basibranchial

support gill filaments (breathing)

Ceratobranchials

has teeth: food grinding

Lower Pharyngeal Bone

connects upper part of gill arches

Epibranchials

upper support for gill system

Pharyngobranchials

Filter food particles and protect gills (prevent debris from entering

Giill rakers

flexible rod that supports the body; primitive backbone

Notochord

Support body, protect spinal cord, allow movement

Vertebral column

Main body of vertebra; supports weight

Centrum

Protects the spinal cord

neural arch

attachment for muscles

neural spine

protects blood vessels (tail region)

hemal arch

muscle for tail movement

hemal spine

connect verterba in front; stability

neural prezygapophyses

connect vertebra behind; stability

neural postzygapopyses

helps stabilize tail vertebrae

hemal prezygapophyses

extra support in tail

hemal postzygapophyses

Support body + help in movement

Ribs and intermuscular bones

protect internal organs

Pleural ribs

support upper muscles

Epineural bones

side muscles

Epipleural bones

main part for swimming/propulsion

Caudal complex

supports tail fin base

Urostyle

supports upper tail fin rays

Epurals

strengthen tail structure

uroneurals

main support for tail fin rays

Hypurals

small rays for stability

Procurrent rays

,main propulsion (top)

Principal rays_upper lobe

main propulsion (bottom)

principals rays_lower lobe

support movement and steering

Pectoral Girdle

connects girdle to skull

Supratemporal

links girdle to neurocranium

Posttemporal

supports upper part of girdle

Supracleithrum

extra suppoprt/stability

Postcleithrum

main support bone; anchors muscle

Cleithrum

helps form fin joint: muscle attachment

Scapula

strengthens fin base

coracoid

used for movements/ steering in water

Fin rays

balance stabilization and movement

Pelvic girdle

base support of pelvic fin

Pelvic bone

main support for pelvic fin

coracoid

connects parts of girdle: add strength

mesocoracoid

opening for nerves/blood vessels

Scapular foramen