The Diverse Patterns of Metamorphosis in Gonostomatid Fishes — An Aid to Classification

Abstract

The gonostomatid lightfishes rank second only to myctophid lantern-fishes in abundance in the sea. The gonostomatid genus Cyclothone has been singled out as the most abundant group of fishes in the ocean. These observations were based on abundance of adults in mid-water trawl hauls. If abundance is based on larvae, the gonostomatid genus Vimiguerria could be the most numerous group of fishes in the ocean. Without attempting to decide whether Cyclothone or Vinciguerria ranks first in abundance, we can assume that the gonostomatids obviously are an important group of oceanic fishes. Grey (1964), in her impressive contribution on gonostomatid fishes, recognized 21 genera as valid, with between 52 to 55 valid species. A few species subsequently have been added and a few synonymized, bringing the number of species close to 60. Weitzman (in press) will reduce the number of genera to 20 (pers. corn.). The Gonostomatidae are closely related to the hatchetfishes, family Sternoptychidae: the most recent review of the latter family was made by Baird (1971). Life histories have been published for 12 of the 20 genera of gono-stomatid fishes and for slightly more than a third of the species. In addition to the published record I have larval series for an additional 3 genera and 9 species.