Species: Microdesmus retropinnis, Double-spotted worm-goby, Rearfin wormfish

under eye - 2 bars

pectoral 10
Microdesmus retropinnis Jordan & Gilbert, 1882
Rearfin wormfish, Double-spotted worm-goby
Slender, wormlike, body height 3-9% of SL; tail (without fin) < 50% of SL; eyes not tiny, on side of head, not skin covered; snout rounded; snout and jaw with pronounced longitudinal swollen muscular ridges; mouth small, little oblique, lower jaw strongly projecting, a small fleshy knob at tip of chin; lips with a restricted free flange at sides; teeth partly in 3 rows; gill opening large (not tubular), but < base of pectoral; dorsal fin spines evenly spaced, 47-49 elements, origin ~ 2 head lengths behind head, almost midway between tip of lower jaw and anus; anal II, 28-32; pectoral 10 rays, fin short; pelvics I, 3, shorter than pectorals; tail fin rounded, as long as head; dorsal and anal fins confluent with tail fin; scales small, non-overlapping, well separated; at base of dorsal and anal fins scale rows diverge outwards and backwards; scales with 39 radiating lines.
Translucent light olive; 2 dark bars under eye; a series of irregular oval dark blotches along top of back and another series along each side; fins translucent except that blotches on top of back extend slightly onto dorsal fin; sides of head and chin irregularly spotted with brown.
Size: 12.5 cm.
Habitat: intertidal rock pools and beachrock.
Depth: 0-5 m.
Central western Gulf of California to Panama.

High Resolution Map Download
- Salinity
-
- Brackish
- Marine
- Inshore/Offshore
-
- Inshore
- Inshore Only
- Water Column Position
-
- Bottom only
- Bottom
- Habitat
-
- Reef only
- Reef (rock/coral/oyster)
- Reef associated (reef + edges-water column & soft bottom)
- Rocks
- FishBase Habitat
-
- Reef Associated
- Feeding Group
-
- No Data
- Carnivore
- Diet
-
- No Data
- Mobile benthic crustacea (shrimps/crabs)
- Mobile benthic worms
- Egg Type
-
- Pelagic larva
- Benthic
- No data
- Global Endemism
-
- Tropical Eastern Pacific (TEP) endemic
- East Pacific endemic
- All species
- Regional Endemism
-
- Continental TEP endemic
- TEP endemic
- Continent only
- All species
- 3 provinces (Cortez + Mexican + Panamic) endemic
- Continent
- Residency
-
- Resident
- Climate Zone
-
- Northern Subtropical (Cortez Province + Sinaloan Gap)
- Equatorial (Costa Rica to Ecuador + Galapagos, Clipperton, Cocos, Malpelo)
- Northern Tropical (Mexican Province to Nicaragua + Revillagigedos)
- IUCN Red List
-
- Data deficient
- Listed
- CITES
-
- Not listed
- Length Max
-
- 12.5
- Depth Range Min
-
- 0
- Depth Range Max
-
- 5