LAB 2: SHARK INTEGUMENTARY & SKELETAL SYSTEMS

Pp. 31 - 48; 82 - 92

1) Skin and Placoid Scales: Look at the whole mount and cross section of the placoid scales/ skin.  Be able to identify a  placoid scale.

External Features:  Be able to identify: pectoral fin, pelvic fin, head, trunk, tail (caudal fin), dorsal fins, lateral line, ampullae of Lorenzini, mouth, spiracle, gill slits, cloaca, urogenital/urinary papilla, clasper.  NB: You are responsible for being able to tell the difference between male and female sharks based on external anatomy.

 

2)  Elasmobranchii - Shark  Skeleton :

Vertebral Column : Neural spine, neural canal, neural arch, centrum (look at a cross section of your shark to see these in more detail)

Dorsal fins - ceratotrichia & fin spine (which has been cut on your specimen)

Caudal fin .

Pectoral Girdle & Fins: Scapulocoracoid bar, coracoid bar, basal cartilages (pterygiophores; not individual elements); radial cartilages (pterygiophores), ceratotrichia

Pelvic Girdle & Fins:  Puboischiac (Ischiopubic) bar, metapterygium, ceratotrichia, clasper

Chondrocranium : Know the following structures - Rostrum, Olfactory capsule, orbits, antorbital and postorbital processes; otic capsule; endolymphatic fossa; basal plate, Optic foramen, superficial opthalmic foramina; foramen magnum, occipital condyles; glossopharyngeal foramen, vagus foramen.  Find the optic pedicel (or know where it should be located if it has been broken off the dried chondrocranium).

Splanchnocranium:  Mandibular arch, palatopterygoquadrate (or simply palatoquadrate) cartilage; labial cartilage, Meckels cartilage, orbital process.  Hyoid arch, hyomandibular cartilage; Visceral arches three to seven, pharyngobranchial cartilage, epibranchial cartilage, ceratobranchial, hypobranchial and basibranchial cartilages; gill rakers and gill rays, teeth.