Zoology.'] NATURAL HISTORY OF VICTORIA. \Fiahes, 



Plate 115. 



LANIOPERCA MORDAX (Gunth.). 



The Skip-jack Pike. 



[Genus LANIOPERCA (Gunth.) = NEOSPHYRJENA (Castel.) = DINOLESTES 

 (Klunz.). (Sub-kingd. Vertebrata. Class Pisces. Sub-class Teleostei. Order Acan- 

 thopterygii. Family Sphyramidaj). 



Gen. Char. — Body compressed, elongate, covered with deciduous cycloid scales of moderate 

 size. Head sharp-pointed, covered with small scales ; cleft of mouth wide, lower jaw projecting 

 in front of upper one. Teeth in villiform bands on vomer, palatines, and jaws ; an outer series 

 of stronger, and one or two pairs of very large, lauiary, teeth in front of upper jaw. Tongue 

 smooth ; eyes lateral, moderate ; seven branchiostegal rays ; pseudobranchiae. Fins : Two 

 dorsal, anterior one short, of 5 spines ; anal with 2 spines ; ventrals nearly under pectorals. 

 No denticulation on plates of head; margins of opercular pieces thin and membranous. 

 Australia.] 



D. 5 + 2, 18; A. 3, 26; V. 1, 5j P. 16; C. 18; L.L. 67J r . 



Description. — Form semiovate; head pointed, with a slightly concave profile; 

 abdominal outline much more convex than the dorsal line. Height of body about 5 

 times in total length (without caudal) ; length of head, about 3^ in the same ; eye 

 nearer to end of operculum than to end of snout ; diameter of eye equal to interorbital 

 space, about f^ of length of head; maxillary not quite reaching vertical from front 

 margin of eye. Preoperculum with a wide obtuse sinus in posterior edge; lower angle 

 forming a rounded finely-serrated lobe. Teeth of lower jaw much larger than upper 

 jaw, 4 or 5 posterior ones large, distant, laniary ; outer row of upper jaw nearl} T equal, 

 small, and about their length apart. Pectoral fin ovate, less than half the length of 

 the head, of 16 rays; ventrals deltoidal, united below, slightly behind base of pectorals ; 

 1st dorsal of 5 slender spines, about 1* its length in front of 2nd dorsal, which is 

 high in front and of 2 simple and 18 branched rays; anal shaped like 2nd dorsal, 

 of 3 simple and 26 branched rays; caudal forked, lower lobe largest, of 18 long 

 rays and 7 or 8 short ones on upper and lower edges. Scales large, very deciduous, 

 lateral line very prominent, nearly straight from upper edge of operculum to middle 

 of tail ; 67 along lateral line, 6 above and 11 below it. Color: Top of head, back, 

 and sides dark purplish-grey, fading into whitish on throat and belly ; first dorsal, 

 pectoral, and ventrals nearly colorless ; 2nd dorsal pale yellowish-olive ; anal lighter ; 

 caudal yellowish-olive ; 2nd dorsal and anal fins with rows of minute dark dots 

 crossing the rays. Iris silvery white. Measurements : Total length of average 

 specimen from tip of snout to tip of caudal fin, 1 ft. 7 ins. 6 lines. Proportional 

 measurements (taking total length as 100) : From tip of snout to middle of caudal, 

 T 9 ^; to base of caudal, T W; to front edge of 1st dorsal, yVtt ? to front edge of 

 2nd dorsal, T 4 «^ ; to front edge of anal, f^- ; to base of pectoral, T 2 / - ; to front 

 edge of ventrals, T 2 ^ ; to front edge of orbit, T \rV ; to hind edge of orbit, ^ ; to 

 tip of operculum, -f^ ; length of pectoral, ^VV ? length of ventral, i*j>; width of 

 ventrals, y^ ; length of anal, $?■$ ; greatest depth at 2nd branched ray, , *-„ ; 

 length of 1st ray, tot 5 length of last ray, tou; length of 1st dorsal, T (; cr ; greatest 

 height at 2nd spine, ^^ ; length of 2nd dorsal, T £$ ; greatest height at 4th branched 



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