Notes on Argentina sialis Gilbert, an Isospondylous Fish of Western North America

Abstract

ARGENTINA SIALIS was originally described by Gilbert (1890: 56-57) from Albatross 3017. The locality of this is given by Tanner (1892: 495) and by Townsend (1901: 407) as latitude 29? 54' 30 north, longitude 113? 01' 00 west. As computed from British Admiralty chart 2324, published April 9, 1879, this falls within the Gulf of California, approximately 14 nautical miles west of Cabo de Lobos, Sonora. Thereafter the locality at which this species had been taken became confused in the literature. Goode and Bean (1895: 510) erroneously referred to it as station 3077 (in southeastern Alaska), and added the words, coast of Jordan and Evermann (1896a: 526), while repeating the original description with but minor alterations, stated the range of the species as of The same authors (1896b: 295) repeated this statement later in the same year and referred Albatross 3017 to the of Meek (1916: 143) attributed Argentina sialis to Californian coast, one specimen. All these references were published before Higgins (1920: 87) recorded specimens of this species from off Huntington Beach, California. It has therefore seemed desirable to verify the type-locality as published by Gilbert. An examination of the records of the U. S. National Museum has indicated, however, that the correct data were published in connection with Gilbert's original description. So far as I have yet found, specimens of Argentina sialis have been definitely recorded only from the two localities previously mentioned, that is, from off Cabo de Lobos, Sonora, and from off Huntington Beach, California, although the range of the species has been given as of California by Ulrey and Greeley (1928: 4), Ulrey (1929: 3), and Jordan, Evermann, and Clark (1930: 68), and as of southern California by Barnhart (1936: 18). It now becomes possible to record a northerly extension of the range of this species of more than 300 miles in a general coastwise direction. Two specimens of Argentina sialis (Stanford Natural History Museum Cat. No. 35311) were taken in an otter trawl by T. Ferranti on April 19, 1941, in Monterey Bay, Monterey County, California. The approximate location was latitude 36? 45' north, longitude 121? 53' west, as computed from U. S. Coast and Geodetic Survey chart 5403 (Monterey Bay), published November, 1926. The larger specimen is 174 mm. in length to caudal, and 204 mm. (8312 inches) in total length. The latter measurement is a matter of interest in view of the fact that Gilbert's original description was based upon A single specimen 3 inches long, while Higgins (loc. cit.) also refers to Argentina sialis as, This little fish, about three inches long. The smaller Monterey Bay example is 143 mm. in length to caudal and 168 mm. (65/% inches) in total length. The dorsal count is ii, 8 in the larger specimen, in which both rudimentary rays are broken off. In the smaller, the dorsal count is ii, 9, the