Document Type

Article

Department/Program

Virginia Institute of Marine Science

Publication Date

1979

Journal

Bulletin of Marine Science

Volume

29

Issue

3

First Page

365

Last Page

379

Abstract

Five hundred twenty-two vexillifers of an unnamed species of the carapid genus Echiodon are reported from ichthyoplankton collections made in the Caribbean Sea, Gulf of Mexico, Middle Atlantic Bight, Sargasso Sea, and Scotian Shelf. These are compared with 36 vexi1lifers and one juvenile of the only other known western Atlantic carapine, Campus ber- I/ludensis, as well as two small unidentified western Atlantic vexillifers, and eight eastern Pacific vexillifers of E. exsiliul/l. Vexillum placement relative to anal-fin origin, myomeres, and vertebral centra appears to be a useful character for separating Echiodon vexillifers from other western Atlantic carapids. The vexillum in Echiodon is posteriad of a vertical through the anal-fin origin, over myomeres 9 to 12 and centra 10 or II. The vex ilium of Echiodoll sp. was examined in detail and is bilateral, each component of which consists of a distal and proximal element. The paired proximal elements rest on a distal cartilaginous radial which is supported by a slipper-shaped, compound cartilaginous proximal radial (pterygiophore) in Echiodoll sp. and by a rod-shaped, simple proximal radial in C. bl'Ymudellsis. The structure is covered by a fleshy sheath which is highly ornamented in C. bermudellsis but less so in Echiodoll sp. The presumed origin of percoid predorsal bones from an ancestor with vexillar supporting structures is questioned. Most available vexillifers of Echiodoll sp. were captured in the eastern Gulf of Mexico. Additional larger size classes were taken from off Bermuda and north of Cape Hatteras to the Scotian Shelf. These and several other subtropical teleost larvae appear to be regularly dispersed northward by the Gulf Stream.

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