
1) Larva
Found on
https://www.crosswordclues.com/clue/leptocephalus

A leptocephalus (meaning `slim head`) is the flat and transparent larva of the eel, marine eels, and other members of the Superorder Elopomorpha. This is one of the most diverse groups of teleosts, containing 801 species over the span of 24 orders, 24 families, and 156 genera. It is supposed that this group arose in the Cretaceous period over 14.....
Found on
http://en.wikipedia.org/wiki/Leptocephalus
[genus] Leptocephalus is a genus that was used for species of larval eels, called leptocephali, that were thought to be new fish species, or whose adult eel species were not known. Leptocephali differ so much in appearance from their adults that the larvae and adults of eels are not easily matched, and when first discovered, leptocephali we...
Found on
http://en.wikipedia.org/wiki/Leptocephalus_(genus)

(from the article `eel`) ...and Notacanthiformes). A prolarva, hatching from a relatively large egg (up to 2.5 millimetres [about 332 inch] diameter), rapidly becomes a ... ...of the Atlantic, at depths of 400 to 700 metres (about 1,300 to 2,300 feet), in an area centred near latitude 26° N longitude 55° W called the ... ...e...
Found on
http://www.britannica.com/eb/a-z/l/36

(lep″to-sef´ә-lәs) a person with an abnormally tall, narrow skull.
Found on
http://www.encyclo.co.uk/local/21001

(Gk: leptos=fine, small, delicate; kephale=head; small-headed) the leaf-shaped larval form of all eels.
Found on
http://www.seafriends.org.nz/books/glossary.htm

[
n] - slender transparent larva of eels and certain fishes
Found on
http://www.webdictionary.co.uk/definition.php?query=leptocephalus

leptocephalus (s), leptocephali (pl) 1. A person with an abnormally tall, narrow skull. 2. A type of larval stage found in a variety of marine bony fishes; that of the common eel is transparent, with a leaf-like body and tiny eyes.
Found on
http://www.wordinfo.info/words/index/info/view_unit/1173/
noun slender transparent larva of eels and certain fishes
Found on
https://www.encyclo.co.uk/local/20974
No exact match found.