CLASSIFICATION OF AMIA CALVA (BOWFIN)
Phylum :- CHORDATA (Notochord and dorsal tubular nerve cord present and gill-slits present).
Group :- CRANIATA (Cranium with brain present).
Subphylum :- VERTEBRATA (Vertebral column present).
Division :- GNATHOSTOMATA (Jaws and paired appendages present).
Super class :- PISCES (Paired fins , gills and skin with scales)
Class :- OSTEICHTHYES (Bony fishes).
SUB-CLASS :- ACTINOPTYERGII (Ray finned fish).
SUPER ORDER :- HOLOSTEI (Bony ganoids).
Order :- AMIIFORMES (Tail heterocercal and overlapping cycloid scales).
FAMILY :- AMIIDAE
GENUS :- Amia
SPECIES :- calva
Amia calva is abundantly distributed in rivers and lakes of Central and Southern America. Upper Jurassic and Lower Tertiary.
HABIT AND HABITAT
Amia is a fresh-water and carnivorous fish, feeding voraciously upon other fishes, insects and crustaceans.
GENERAL CHARACTERSTICS OF AMIA CALVA (BOWFIN)
- Commonly known as Bowfin, measuring about 60 cm in length.
- Shape of body is fusiform, compressed and divided into head, trunk and tail.
- Body covered by uniformly thin, overlapping and nearly cycloid scales.
- Head contains ventral mouth and dorsal eyes. The terminal mouth has a thick upper lip and a pair of dorsal barbels.
- Middorsal fin has long base and continuous for the greater part of the trunk and tail and contains about 48 rays. All fins short and devoid of fulcra. Paired fins are pectoral and pelvic. Anal fin near fan-shaped caudal fin.
- Air bladder often used as lung. Fish can breath atmospheric air and comes to the surface to engulf air into air bladder. Pyloric caeca absent.
- Tail is homocercal, lateral line distinct.
- Sexually dimorphic. Males are smaller than females (45 cm) and provided with a rounded black spot at the base of caudal fin. Two peculiar comb-like structures are found on the head.
- Male builds a nest in water weeds and guards the young until they can move themselves.
- Amia calva is the only one living species. Amia shows combination of primitive and advanced characters. The primitive characters include
- Dorsal, cellular and bilobed lung (air bladder)
- Spiral valve vestigial
- Large jugal plate, well-developed branchiostegal rays
- Non-pyloric caeca.
- The advanced characters include
- Thin cycloid scales without ganoin
- Fulcra absent in fin
- Tail homocercal and
- Vertebrae solid and amphicoelous.
- This fish also shows parental care.
- This fish has continuous dorsal fin, anti above features, hence it is Amia.