FAO family account and key to WA Eleotridae
by E.O. Murdy and D.F. Hoese

Eleotridae

sleepers

 

 

Diagnostic characters: Typically small to medium‑sized (most do not exceed 20 cm, although Gobiomorus from this area may reach 60 cm), bottom-­dwelling fishes. Many are relatively inactive, hence, the common name of sleeper. Six branchiostegal rays; pelvic fins separate and not connected by membrane. Typically, body stout; head short and broad; snout blunt; gill membranes broadly joined to isthmus; scales small or large and either cycloid or ctenoid; two separate dorsal fins, first dorsal fin with 6‑7 weak spines, second dorsal fin with one weak spine followed by 6‑12 soft rays; caudal fin broad and rounded, comprising 15 or 17 segmented rays; anal fin with one weak spine followed by 6‑12 soft rays; pelvic fin long with one spine and five rays; pectoral fin broad with 14‑25 rays. The second dorsal fin and the anal fin relatively short‑based; origin of anal fin just posterior to a vertical with origin of second dorsal fin; terminal ray of second-dorsal and anal fins divided to its base (but counted as a single element.) Head typically scaled, scales being either cycloid or ctenoid.  Head with a series of sensory canals and pores as well as cutaneous papillae.  No lateral line on body. Teeth usually small, conical and in several rows in jaws.

Colour: not brightly colored, most are light or dark brown or olive with some metallic glints.

 

Habitat, biology, and fisheries: Sleepers typically occur in fresh or brackish waters, although some species are truly marine. Sleepers are omnivorous. Found in all subtropical and tropical waters (except the Mediterranean and its tributaries).  Comprises approximately 40 genera and 150 species; 5 genera and 10 species are recorded from this area.  Of no commercial or recreational importance other than as food for larger fishes.  Occasionally the larger species may be seen in local markets.

 

Similar families occurring in the area:

Gobiidae: base of second dorsal much longer than distance from end of second dorsal fin to base of caudal fin; pelvic fins connected to form a disc in species from fresh and brackish water, separated only in species living on or around reefs.  Size small; adults typically less than 10 cm in length.

 

 

KEY TO THE ELEOTRIDAE IN THE WESTERN ATLANTIC FISHING AREA 31

* Exclusive of the dwarf freshwater genera Microphilypnus and Leptophilypnus

 

1a. Prominent, ventrally pointed spine on preopercle present, this spine may be
difficult to see as it is is often covered by skin.........................................................2

1b. Preopercular spine absent.................................................................................3

 

2a. Scales cycloid and smooth, about 90 longitudinal rows; caudal fin extending
anteriorly onto body; body very slender, elongate, and terete, the depth
contained 7 to 9 times in standard length……………………………(emerald sleeper) Erotelis smaragdus

2b. Scales ctenoid and rough, 40-65 longitudinal rows; caudal fin not
extending anteriorly on body; body depth moderate..........................................Eleotris  

The taxonomy in this genus is unresolved, thus, a key is not yet available.  See list of species below.

 

3a. First dorsal fin with 6 spines; body with about 40-65 longitudinal
scale rows; body and head strongly compressed................(bigmouth sleeper) Gobiomorus dormitor

3b. First dorsal fin with 7 spines; body with fewer than 40 or more
than 90 longitudinal scale rows; body deep.................................................................4

 

4a. Scales very small, about 110 longitudinal scale rows........................Guavina guavina

4b. Scales large, about 25 to 35 longitudinal scale rows............…..................Dormitator

The taxonomy in this genus is unresolved, thus, a key is not yet available.  See list of species below.

 

List of species occurring in the area:

 

Dormitator cubanus Ginsburg, 1953; to 10cm; freshwater, Cuba

Dormitator lophocephalus Hoedeman, 1951; to 9cm; Surinam

Dormitator maculatus (Bloch, 1792); to 30cm, common to 14.5 cm; fresh and
brackish waters, Chesapeake Bay to northern Gulf of Mexico southward to s.e. Brazil

 

Eleotris amblyopsis (Cope, 1871); to 8.3cm; northern and northeastern South America

Eleotris belizanus Sauvage, 1880; to 10cm; Belize, French Guiana

Eleotris perniger (Cope, 1871); to 13cm; St. Martin Island

Eleotris pisonis (Gmelin, 1789); to 25cm, common to 12.5cm; fresh and brackish waters,
South Carolina, Bermuda, Bahamas, and northern Gulf of Mexico to s.e. Brazil

 

Erotelis smaragdus (Valenciennes in C & V, 1837); to 20cm; marine waters,
southeastern
Florida, Bahamas, and northern Gulf of Mexico to Brazil

 

Gobiomorus dormitor Lacepède 1800; to 60cm, commonly to 36cm; fresh and
brackish waters, southern
Florida & southern Texas to eastern Brazil

 

Guavina guavina (Valenciennes in C & V, 1837); to 30cm; Cuba, Puerto Rico, Mexico, Panama to Brazil