Monolene sessilicauda

FamilyScientific NameAuthorYearCommon Name
BothidaeMonolene sessilicaudaGoode1880Deepwater Flounder

Monolene sessilicauda

Unique Characters: Eyed side tan to brownish with dark blotches loosely arranged into bands. Pectoral fin banded on eyed side. Caudal fin may have a dark, central blotch. Mouth small, eyes closely set. Arched portion of lateral line squarish. Pectoral fin absent on blind side of adults. Ocular-side pelvic-fin base about equal in length with that of blind-side fin, with first rays not inserted anterior to those of blind-side fin. Body very elongate, depth 33-37% standard length.

Similar Species: Slim Flounder, Monolene antillarum. Pectoral with irregular blackish cross-bars, which are more distinct in its lower half. Body elongate and brownish with indistinct darker markings, of which those near edges of body are most prominent. Pectoral fin absent on blind side. Depth of body 3-3.2 in the length. Length of head 4.5. Upper profile of head less elevated above and behind eyes. Diameter of eye 3.25-3.5 in length of head. Lower jaw a little longer and rather more vertical. 8 or 9 gill rakers on lower part of anterior arch. 87 or 88 scales in lateral line.

Readily distinguished from the more northerly M. sessilicauda by the narrower body; larger head and larger eye and pectoral fin.

Note: Slim Flounder, Monolene antillarum Norman 1933, may be a synonym of Deepwater Flounder, M. sessilicauda (FAO 2002).

Reference: Norman, J. R. 1933. Notes on flatfishes (Heterosomata). — V. Four new species from the Atlantic coast of America. Annals and Magazine of Natural History. Series 10. Volume 12. Number 68. Article 21:201-204.

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