The most up-to-date book is probably:  Allen, G.R. and D.R. Robertson. 1994.
Fishes of the tropical eastern Pacific.  University of Hawaii Press,
Honolulu, HI. 332 p.  It contains taxonomic descriptions and lots of color
photographs, but no keys.

The Ecuadorian Instituto Nacional de Pesca published a list of marine fishes
of Ecuador in 1969.  I don't know how complete or accurate it is, but it
looks pretty good for the fishes I have looked up.  It doesn't contain keys
nor ID characteristics, but lists family, genus, species, Spanish common
name, and English common name.  It contains 40 figures.  The citation is:
Cobo, M. and S. Massay. 1969. Lista de los peces marinos del Ecuador.  Inst.
Nac. de Pesca del Ecuador, Boletin Cientifico y Tecnico 2(1). 68 p.  If you
are interested in seeing it, and in the likely event that your library does
not have it, contact me personally.
----------------------------------------------------
>Good morning,
>
>I need to find keys or identification guidebooks for fish and
>invertebrates of coastal Ecuador ... does anyone have suggestions?
>Primary literature is OK!
>
>Thanks very much,
>
>Kath Kavanagh
>
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  Robert J. Olson   ([log in to unmask])
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  Inter-American Tropical Tuna Commission
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