| Common names: blenny (English), trambollo (Espanol) |
Exerpes asper (Jenkins & Evermann, 1889)
Elongate, compressed; snout long, pointed, upper profile straight; no cirri on head; lower jaw projecting; teeth in jaws biserial with larger outer series; roof of mouth with teeth on center but not sides; operculum with a distinct spiny projection; dorsal fin III- IV + XXIV- XXV, 0-2, front 3-4 spines in a high finlet well separated before rest of fin; anal rays II, 17-20; lateral-line scales about 40.
Green with midlateral white stripe from snout to caudal fin base (may be broken into series of spots); a pair of ocellated dark spots on rear half of dorsal fin.
Maximum length, 6.5 cm.
Habitat: common among sargassum weed or eelgrass.
Depth: 1-10 m.
Central Baja and most of the Gulf of California.
Global Endemism: All species, East Pacific endemic, Tropical Eastern Pacific (TEP) endemic
Regional Endemism: All species, TEP endemic, Continental TEP endemic, Cortez province endemic, Continent, Continent only
Climate Zone: North Temperate (Californian Province &/or Northern Gulf of California), Northern Subtropical (Cortez Province + Sinaloan Gap)
- Hastings, P.A. and V.G. Springer 2009 Recognizing diversity in blennioid fish nomenclature (Teleostei: Blennioidei). Zootaxa 2120:3-14. (Ref. 82814)
- Allen, G.R. and D.R. Robertson 1994 Fishes of the tropical eastern Pacific. University of Hawaii Press, Honolulu. 332 p. (Ref. 11482)
Catalog Number: USNM 39643
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Fishes
Preparation: Photograph; Radiograph
Collector(s): O. Jenkins & B. Evermann
Locality: Gulf of California, Mexico, Pacific
- Type: Jenkins, O. P. & Evermann, B. W. 1888 (1889). Proceedings of the United States National Museum. 11 (698): 154.
Inshore/Offshore: Inshore, Inshore Only
Water Column Position: Bottom, Bottom only
Habitat: Reef (rock &/or coral), Reef only, Rocks, Macroalgae, Reef associated (reef + edges-water column & soft bottom)
FishBase Habitat: Reef Associated
Habitat and Ecology
Water temperature and chemistry ranges based on 1 sample.
Depth range (m): 1 - 8
Temperature range (°C): 22.443 - 22.443
Nitrate (umol/L): 3.645 - 3.645
Salinity (PPS): 35.261 - 35.261
Oxygen (ml/l): 4.879 - 4.879
Phosphate (umol/l): 0.897 - 0.897
Silicate (umol/l): 7.763 - 7.763
Depth range (m): 1 - 8
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.
Diet: mobile benthic worms, mobile benthic crustacea (shrimps/crabs), mobile benthic gastropods/bivalves, sea-stars/cucumbers/urchins, soft corals/hydroids
Life History and Behavior
Molecular Biology and Genetics
Statistics of barcoding coverage: Exerpes asper
Public Records: 1
Specimens with Barcodes: 6
Species With Barcodes: 1
CITES: Not listed
IUCN Red List Assessment
Red List Category
Red List Criteria
Exerpes asper, the Sargassum blenny, is a species of labrisomid blenny native to the Gulf of California and the Pacific coast of Baja California. It is currently the only known member of its genus.
The Sargassum blenny has two quite distinct dorsal fins. The face is elongated and the mouth resembles that of a pike. There are no cirri. The general colour is brown with patches of silver on the flanks and there are 2 blue eyespots on the posterior dorsal fin. This fish grows to a length of 6.5 centimetres (2.6 in) TL. 
The Sargassum blenny lives among sargassum seaweed or in seagrass meadows where it is well camouflaged. It is found among the fronds of floating Sargassum mats. When threatened it tends to curl its head round near its tail and remain motionless, relying on its cryptic appearance to escape detection.
- Hastings, P. & Dominici-Arosemena, A. 2010. Exerpes asper. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <www.iucnredlist.org>. Downloaded on 21 November 2013.
- Froese, Rainer and Pauly, Daniel, eds. (2013). "Exerpes asper" in FishBase. October 2013 version.
- Thomson, Donald A.; Lloyd T. Findley; Alex N. Kerstitch. Reef fishes of the Sea of Cortez. p. 216.