Macrurus asper Goode & Bean, 1883, new species
Creators: name: Goode, G. B.
name: Bean, T. H.
Publisher: name: Zenodo
Year: 1883
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Actinopterygii
Pleuronectiformes
Pleuronectidae
Macrurus
Macrurus asper

description: 8. Macrurus asper, new species. The relations of this species appear to be with M. Bairdii, from which it dilfers in (1.) its longer snout, (2.) the location of the vent, which is much farther back, and (3.) the absence of keels upon any of its scales. The length of the specimen described is 322 millimeters. The body is much stouter than in M. Bairdii, its greatest height being contained times in its length. The scales are small, strong, the free portions covered with vitreous spines arranged in about seven rows; there is no specialization of the central row, as in M. Bairdii, though the median spine at the margin of the scale projects most strongly. The number of scales in the lateral line is about the same, there being about 150; there are 7 above and 18 below the line. Length of head contained 5| times in total length. Width of interorbital area a little greater than horizontal diameter of orbit and length of operculum, and contained 4\ times in the length of the head. Length of snout about equal to width of interorbital space and about one half the postorbital portion of the head. Snout triangular, depressed, its tip in the axis of the body, and nearly on a level with the lower margin of the eye; its lower surface forming an angle with the body axis, about equal to that formed with same by its upper profile. The superior ridge is pronounced anteriorly, but ends in advance of the concavity in the interorbital space. The lateral ridges are prominent, and continue posteriorly to the eye, with strong angular projections in front of the nostrils. No ridges continued from supraorbital region. Nostrils rather close to the eye. Barbel shorter than the eye. Tip of lower jaw under anterior nostril, cleft of mouth under posterior margin of orbit. Teeth in the jaws in a very narrow villiform band, the outer series slightly larger: those in lower jaw apparently in single series, moderate. Distance of first dorsal from snout equal to nearly four times the length of its base, its distance from the anterior margin of the orbit equal to the length of the head. First spine minute; second spine nearly two thirds the length of the head, and when laid down is far from reaching to the origin of the second dorsal. When the fin is erect, its superior margin is nearly at right angles to the plane of the back, and slightly convex. The distance between the two dorsals is twice the length of the base of the first, the second beginning in the perpendicular from the fifth ray of the anal. The anal is about three times as high as the second dorsal. The vent is under the 30th scale of the lateral line directly in advance of the anal, and at a distance from the ventral considerably greater than the length of that tin, in this respect differing widely from M. Bairdii. Distance of pectoral from snout slightly more than the length of the head. Its length is less than that of the dorsal spine, and slightly more than half its distance from the snout. Its insertion (upper axil) is in the middle line of the body. Insertion of ventral under that of pectoral, and slightly in advance of that of dorsal. Its first ray is not greatly prolonged, and is about half as long as the distance of the fin from the snout. Radial formula: 1st D. II, 8-9; 2d D. 105; A. 110; P. 20; Y. 10. Scales, 7-150-18. Color dark reddish brown, the spines upon the scales with a metallic lustre.
description: Published as part of Goode, G. B. & Bean, T. H., 1883, Reports on the results of dredging under the supervision of Alexander Agassiz, on the east coast of the United States, during the summer of 1880, by the U. S. coast survey steamer " Blake, " Commander J. R. Bartlett, U. S. N., commanding., pp. 183-226 in Bulletin of the Museum of Comparative Zoology at Harvard College 10 (5) on pages 196-197, DOI: 10.5281/zenodo.28095