Collette and Gillis Osteological differences between two species of Grammatorcynus 



15 



Figure 2 



Variations in lateral line pattern in Grammatorcynus. (a) 

 Usual pattern in G. bilineatus; (b-d) variations in pattern in 

 G. bilineatus; (b) Australia, 410mm FL; (c) Queensland, 

 ^16mm FL; (d) Queensland, 400mm FL; (e) usual pattern in 

 G. bicarinatus; (f) variation in pattern in G. hicarinatus. 

 Western Australia, 765 mm FL. 



shows the range and mean of all the characters as 

 thousandths of fork length, and eight of the characters 

 as thousandths of head length (Table 1). Scatter 

 diagrams, with regression lines, show two of the best 

 morphometric characters: G. hicarinatus has a smaller 

 orbit (Fig. 3), and a longer first dorsal fin base (Fig. 4). 



MerJstJc characters 



Numbers of fin rays (first dorsal spines, second dorsal 

 rays, dorsal fmlets, anal rays, anal finlets, and pectoral 

 rays), gill rakers, and teeth on the upper and lower jaws 

 are systematically valuable in Grammatorcynus. They 

 are discussed in the relevant osteological sections of 

 the paper. 



culum, and continue posteriorly to the anal fin. They 

 are found below the ventral lateral line on both sides 

 of the fish. No spots were present in the two smallest 

 specimens examined (AMS IB.5207-8, 306-315mm 

 FL). Spots are never present in G. bilineatus (Fig. lA). 



Morphometric characters 



In addition to fork length, 26 measurements were 

 routinely made on all specimens. Several morphometric 

 characters separate the two species. A summary table 



Soft anatomy 



Viscera Emphasis was placed on the appearance of 

 the viscera in ventral view, after removal of an oval 

 segment of the belly wall. Previous descriptions of the 

 viscera of Grammatorcynus include Kishinouye (1923), 

 Silas (1963), and Collette and Russo (1985b). 



The anterior end of the liver abuts the transverse 

 septum anteriorly in the body cavity. The liver has 

 three lobes. The right and left lobe are longer than the 

 middle lobe, with the right lobe being longest (Fig. 

 5c-d). The liver is similar in shape in Scomberomorus, 



