. Bulletin - United States National Museum. Science. A REVIEW OF THE MYSIDACEA 97 GASTROSACCUS DISSIMILIS Coifmann Figure 29 ? Chlamydopleon aculeatum Obtmann, 1893, p. 25, pi. 2, fig. 1. Gastrosaccus dissimilis Coifmann, 1937, p. 5, fig. 2. Occurrence.—Gulf of Mexico, Calcasieu Pass, La., No. 18, W. H. Spaulding collector, November 1906, 1 adult male. Distribution.—Off the coast of South America, between Pernambuco and Rio de Janeiro (Coifmann); ? mouth of the River Tocantins (Ortmann). The present rec- ord is from the north side of the Gulf of Mexico, off the coast of Louisiana. All these lo
. Bulletin - United States National Museum. Science. A REVIEW OF THE MYSIDACEA 97 GASTROSACCUS DISSIMILIS Coifmann Figure 29 ? Chlamydopleon aculeatum Obtmann, 1893, p. 25, pi. 2, fig. 1. Gastrosaccus dissimilis Coifmann, 1937, p. 5, fig. 2. Occurrence.—Gulf of Mexico, Calcasieu Pass, La., No. 18, W. H. Spaulding collector, November 1906, 1 adult male. Distribution.—Off the coast of South America, between Pernambuco and Rio de Janeiro (Coifmann); ? mouth of the River Tocantins (Ortmann). The present rec- ord is from the north side of the Gulf of Mexico, off the coast of Louisiana. All these localities suggest that the species is a shallow-water coastal form, probably brackish water in habit. Remarks.—This species is very closely related to G. johnsoni but may be distinguished by the presence of a prominent median dorsal spine on the fifth abdominal somite, the longer and more acute rostral plate which extends forward as far as the distal end of the eye, and the somewhat different form of the modified third pleopod of the male. The present specimen agrees closely with the description and figures given by Coif- mann (1937). The third pleopod of the male appears somewhat different from that figured by Coifmann, but this appendage is very difficult to interpret, and, moreover, Coifmann's speci- mens may not have been quite adult. I give here a figure of the third pleopod (fig. 29) in the pres- ent specimen for comparison. For the rest the agreement is so close that I feel justified in iden- tifying it with Coifmann's species. In 1893 Ortmann described a mysid under the name Chlamydopleon aculeatum, captured at the mouth of the Tocantins River, on the north coast of South America. The species ought certainly to be referred to the genus Gastrosaccus, but Ort- mann's description is so inadequate that it is impossible to identify the species. I suggest that it is the same as G. dissimilis. There is nothing in Ortmann's descrip- tion and figures against this suggestion
Size: 802px × 3116px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorun, bookcentury1800, bookdecade1870, booksubjectscience
