Pacific croaker (Johnius pacificus) fish species and information / pictures of Pacific croaker - Johnius pacificus

Pacific croaker (Johnius pacificus) fish species information

Scientific Name
Johnius pacificus

Common Name
Pacific croaker

Biology
Dorsal spines (total): 11; Dorsal soft rays (total): 25-29; Anal spines: 2; Anal soft rays: 7. Eye small, 11 to 16 % of head length; snout bluntly rounded; no barbel on chin; teeth differentiated into large and small in both jaws; gill rakers slender, about half the length of gill filaments at angle of arch, 10 to 13 on lower limb. Second anal spine long, stiff, 45 to 54 % of head length. Scales on head and throat cycloid (smooth). Swim bladder hammer-shaped, with about 12 pairs of arborescent appendages along its sides, the first entering head and sending a palmate branch to the front of the pectoral arch. Sagitta (large earstone) with a tadpole-shaped impression, the head of which has its long axis lying obliquely to that of sagitta and the tail expanded and deepened as a hallow cone connected with the head by a narrow groove.

Classification

Classified By
Hardenberg, 1941
Class
Ray-finned fishes (Actinopterygii)
Order
Perch-like fish (Perciformes)
Family
Drums or croakers (Sciaenidae)

Distribution

Region
Western Central Pacific
Distribution
Western Central Pacific: northern (=Pacific) coasts of New Guinea.
Range
Unknown

Environment

Climate
Tropical
Water Temperature From
Unknown °C
Water Temperature To
Unknown °C
Depth From - meters
Unknown m
Depth To - meters
Unknown m
Zone
benthopelagic
Environment
Marine; freshwater; brackish; benthopelagic
Trophic Level
3.23 s.e. 0.39 Based on size and trophs of closest relatives
Occurs in Marine / Salt water
True
Occurs in Brackish water
True
Occurs in Fresh Water
True
Occurs on Reefs
False
Is kept in Aquariums
False

Physical Size and Genetics

Maximum Length
14.0 cm
Common Length
10.0 cm
Phylogenetic Diversity Index
PD50 = 0.5000 many relatives (e.g. carps) 0.5 - 2.0 few relatives (e.g. lungfishes)

Human Uses and Population

Human Uses
Fisheries: of no interest
Vulnerability
Low vulnerability (15 of 100)
Resilience
High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.)
Threat To Humans
  Harmless
IUCN Red List Status
  Not Evaluated