AMERICAN MUSEUM NOVITATES Number 784 Published by The American Museum of Natural History, New York City March 11, 1935 59.7 (81) FISHES FROM RIO JURUA AND RIO PURUS, BRAZILIAN AMAZONAS BY F. R. LAMONTE The Museum has received from B. A. Krukoff a collection of fishes made during 1934 in the following localities. Rio Jurua: collected in the vicinity of the mouth of Rio Embira, a tributary of Rio Tarauaca, which, in turn, is a tributary of Rio Jurua (70° 15′ W., 7° 30′ S.). Rio Purus: collected in the vicinity of the mouth of Rio Macauhan, a tributary of Rio Yaco, which, in turn, is a tributary of Rio Purus (69° W., 9° 20′ S.). Panaque purusiensis, new species DESCRIPTION OF TYPE.-Number 12600, American Museum of Natural History; collected in the Rio Purus, Brazil, 1934, by Boris A. Krukoff. Our only specimen. Length to base of caudal, 114 mm.; depth in this length, 4.4; head, to posterior margin of temporal plate, 3. Eye in head, 9; interorbital, 2.4; snout, 1.7. Head nearly as long as broad, and one and three-quarters times as long as deep. Six spoon-shaped teeth on each ramus of the upper jaw, 5 on each ramus of lower jaw. Snout narrowed anteriorly, supraorbital edges only slightly raised. Supraoccipital with very low median ridge, ending posteriorly in a point; temporal plates not carinate; interoperculum armed with a bunch of bristles, permanently everted, the longest one-fourth the length of head. Scutes spinulose, very weakly carinate, most so on either side of the dorsal and on the anterior five scutes following the clavicle. Not carinate on peduncle except the last two rows which are very weakly so; 25 scutes in longitudinal series, 5 between dorsal and adipose, 11 between anal and caudal. Supraoccipital bordered posteriorly by 3 scutes on each side. Lower surface of head and abdomen completely covered with small granular scales. Dorsal, I, 8, the last ray attached to the following scute by an inconspicuous membrane. Length of the base of dorsal (measured, after Regan, from first branched ray to last, exclusive of spine and of membrane following the last ray) equal to the distance three-fourths of the way to the tip of adipose. Anal, I, 4. Pectoral spine extending to middle of ventral fin. Caudal deeply emarginate; caudal peduncle twice as long as deep. Color in preservative olivaceous with faint traces of alternate light and dark stripes from the back of the head to the caudal base, and on the sides of the body. All fins with about three dark bands which begin on the spines and may be composed of large dots; two bands on the adipose. The ventral surface is faintly mottled as if there had been dark markings. This species differs from others described in the number of scutes bordering the supraoccipital; in its depth; the fact that the temporal plates are not carinate; its dorsal count, the length of the interopercular spines; and the tooth count which is lower than that of the other species.