OCR Text |
Show FISHES OF THE FAMILY CICHLID.E. 157 or moderate, ctenoid or cycloid. Two lateral lines; scales of the lateral lines larger than the rest. Mouth moderate or large ; lower jaw projecting; maxillary exposed distally; teeth conical, in several series in each jaw, those of the outermost series usually slightly or moderately enlarged ; teeth of the inner series depressible. Upper surface of head scaly about to the level of the orbits ; cheeks and opercular bones scaly ; posterior border of prseoperculum finely denticulated. Gill-rakers short, few (8-12 on the lower part of anterior arch). A single dorsal fin, with X V I -X X V 11-19 rays. Anal with III 7-12 rays. Pectoral symmetrical, rounded, with 15-20 rays; ventrals behind the bases of the pectorals. Caudal rounded. Sixteen species from South America. Skeleton. In Crenicichla johanna the skull is depressed and nearly flat above, the supraoccipital and parietal crests being almost obsolete; the former gives rise posteriorly to a rather strong backwardly directed process; a feeble transverse ridge between the orbits forms the posterior border of a broad depression for the reception of the praemaxillary processes, which are rather short and do not reach the frontals. The vertebral column consists of 23 prsecaudal and 18 caudal vertebrae; parapopliyses are developed on the fourth and succeeding praecaudals and are mostly strong and almost horizontal; the first three ribs are sessile, the others inserted on the parapophyses ; the epipleurals, except those of the two anterior ribless vertebrae, are attached either to the ribs or to the parapophyses near the insertion of the ribs; none of the anterior vertebrae shows any trace of inferior apophyses. The pelvic bones diveige anteriorly. The lower pharyngeals are united by a straight suture and form a broad triangular piece. In Crenicichla saxatilis the skeleton is essentially similar, but the cranial crests are more distinct and the longer praemaxillary processes extend to the transverse ridge on the frontals. There are 20 praecaudal and 15 caudal vertebrae. Synopsis of the Species. I. Scales ctenoid, at least on the side of the body below the lateral line; nostril equidistant from tip of snout and eye, or nearer the latter. A. 3 8 -70 scales in a longitudinal series below the lateral line. 1. Maxillary extending beyond anterior margin of eye. 3 8 -4 6 scales in a longitudinal series below the lateral line; depth of body 3 -4 in the length. D. X V I -X V I I I 13-16. 1. lepidota. 50-62 scales in a longitudinal series below the lateral line; depth of body 3|-4J in the length. D. X V I I -X X 13-16. 2. saxatilis. 65-70 scales iu a longitudinal series below the lateral line; depth of body 4 f -5 ^ in the length. D. X I X -X X I 13-14. 3. lucius. 5 1 -5 7 scales in a longitudinal series below the lateral line; depth of body 5-5| in the length. D. X X -X X I I 11-12 . 4. geayi. 2. Maxillary extending to the vertical from anterior margin of eye; 63-70 scales in a longitudinal series below the lateral line. |