Shorefishes of the Eastern Pacific online information system

Español  Contact

Species: Lythrypnus cobalus, Knave goby

All Families:   All Genera:   All Species:

red + blue bars: body 4-7, head 3
D2 I, 18: A I, 14-15
pectoral grey, 21-22
under tail base: 5 black dots
Cocos Island

Lythrypnus cobalus Bussing, 1990

Knave Goby

Body robust; head round; with fleshy crest along top of head and nape; mouth very oblique; head without pores; papillae around mouth, on cheeks and operculum and over eye; front nostril a long tube, rear nostril a raised rim; tongue round to blunt; 5-7 gill rakers; dorsal fin VI (2nd and 3rd spines filamentous in male)+ I, 18 (17-19) rays; I, 14-15 (13-16); anal rays; 21-22 (20-23) pectoral rays; pectoral rays unbranched; pelvics fused into disc; tail fin short, round, with 17 segmented rays; scales rough, none on head, nape, chest and pectoral base; ~ 43 lateral scale rows.

Head and body red; 4-7 thin blue, dark-margined bars on body and 3 on head; dorsal, tail and anal fins orange, paler distally; pectorals and pelvics blue-grey; 5 black dots along underside of tail base.

Size: 2.6 cm.

Habitat: rocky bottoms.

Depth: 25-96 m.

Cocos and Malpelo Islands.

High Resolution Map Download

Species Data Create Report Export as Word File Export as Excel File
  • Marine
  • Marine Only
  • Inshore Only
  • Inshore
Water Column Position
  • Bottom only
  • Bottom
  • Rocks
  • Reef associated (reef + edges-water column & soft bottom)
  • Reef (rock/coral/oyster)
  • Reef only
FishBase Habitat
  • Demersal
Feeding Group
  • Carnivore
  • No Data
  • Planktivore
  • No Data
  • Zooplankton
  • Mobile benthic crustacea (shrimps/crabs)
Egg Type
  • No data
  • Benthic
  • Pelagic larva
Global Endemism
  • East Pacific endemic
  • Tropical Eastern Pacific (TEP) endemic
  • All species
Regional Endemism
  • All species
  • Island (s)
  • TEP oceanic island (s) endemic
  • TEP endemic
  • Island (s) only
  • Multiple oceanic islands endemic
  • Resident
Climate Zone
  • Equatorial (Costa Rica to Ecuador + Galapagos, Clipperton, Cocos, Malpelo)
IUCN Red List
  • Data deficient
  • Listed
  • Not listed
Length Max
  • 2.6
Depth Range Min
  • 30
Depth Range Max
  • 96