CLASS CHONDRICHTHYES

1. Class Chondrichthyes
Mirabel, Camille Joyce Mercado,
Pia Alyssa
Rivera, John David

2. ETYMOLO
G Y - Cartilages
“Chondros’’
“Ichthyos’’
- Fish

3. Class Chondrichthyes
Characteristics:
 Cartilaginous
fishes
 Streamlined form with heterocercal tail
 Cartilaginous skeleton
 Leathery skin
 With placoid scales ( dermal denticles )
 Restricted notochord
 Mouth and two nostrils ventral
 Jaws and paired appendages
 Male claspers
 Eggs with large yolk

4. M O R P H O L O
G Y

5. Taxonomical Hierarchy

Kingdom Animalia
Phylum Chordata
Subphylum Vertebrata
Infraphylum Gnathostomata
Class Chondrichthyes
Subclass Elasmobranchii
Orders Cladoselachii,
Pleuracanthodii ( extinct sharks )
Orders Squaliformes
Order Rajiformes
Subclass Holocephali

6. Subclass
Elasmobranchii
 Sharks (Selachii) and the rays & skates
(Batoidea)
 lives in most oceans in the world

7. Circulatory System
Four chamber heart: sinus venosus,
atrium, ventricle, and conus
arteriosus.
One direction of flow: Heart Gills
Body
Ectotherms/Endotherms

8. Reproductive System
(Male)
 Both testes
functional

Seasonal
reproduction
cycle

Sperm
stored in
seminal
vesicles

Both
claspers
functional

9. Reproductive System (Female)

One functional ovary in most
viviparous species

Seasonal reproductive cycle

Fertilization in nidamental gland

10. Shark Mating

One clasper will rotate 90º and
will be inserted into the female’s
cloaca

Clasper will expand cartilaginous
spurs to anchor in the female

11. Subclass Elasmobranchii:
Orders Cladoselachii,
Pleuracanthodii

extinct sharks

12. Order Squaliformes
 sharks,
body spindle-shaped; 5-7 pairs of
lateral gills not covered by operculum,
pectoral fins not enlarged example:
Squalus

13. Order Rajiformes
 skates,
rays and sawfishes, body
spreadout, pectoral fins enlarged and
attached to head and body; five pairs of
gill slits on ventral side, spiracles large

14. Subclass Holocephali
•
•
•
•
chimaeras or ghost fish , gill slits covered with
operculum;
spirally closed; aberrant shaped; jaws with tooth
plates;
single nasal opening without scales; accessory
clasping organs in male ;
lateral line an open groove, Chimaera

15. Nervous System
 Cerebellum
is small
 Medulla Oblongata is produced laterally
into restiform bodies

16. Digestive System
 The
mouth in holocephali is small as
compared to the wide mouth of
Elasmobranch
 It is bounded by three lips-like fold and
equipped with the tooth plate having
irregular surface and sharp cutting Edges

17. Urogenital System
 The
kidney of holocephalians is
opisthonepric having a large number of
uriniferous tubules and built upon the
basic pattern other fishes.

18. Circulatory System
 Heart
is Built upon the pattern similar to
other fishes.
 The Heart is consists of a sinus venosus,
artrium, ventricle and conus with three
rows of valves.

19. Respiratory System
A
Mandibular pseudobranch is absent and
hyoid bear only a Posterior Hemibranch.
 The first,second and the third branchial
arches have Holobranch but the forth Has
a hemibranch.