LEIS: SYSTEMATICS AND ZOOGEOGRAPHY OF THE PORCUPINEFISHES 



Figure 5.— Head of Dwdon liturosus (CAS 

 30967) showing arrangement of spines in the re- 

 gion of the gill opening. Note that spines on an- 

 terior border of opening are short and flattened. 

 Also note the small dow-nward-pointing spine 

 below the anterior border of the eve. 



Longest Frontal Spine/ SL 



— I © 1 D. liturosus 



1 ® 1 D. hystrix 



1 1 D. eydouxii 



At! D. holocanthus ^ ^ — i 



la-Pac. D. holocanthus 1 1© — 



D nicthemerus 



^ H 



FlGURE 6. — Ratio of frontal spine length to standard length for 

 the five species of Diodon. Line indicates range, circle and bar 

 indicate mean, and vertical bars alone denote ±1 SD. Note dif- 

 ference of spine length between Atlantic and Indo-Pacific 

 specimens of Z). holocanthus . Number of specimens given in de- 

 scription for each species. 



I 1 1 r 



.04 .08 



.12 



-! 1 — 



.16 



.20 



— I — 

 .24 



4a Frontal spines 0.04-0.10 (Figure 6i, much shorter than pectoral axil spines; 17-22 S-A 

 spines; a small downward-pointing spine below the anterior margin of the eye present; 

 dorsal blotches with a distinct light border; a dark gular band from eye to eye under the 



lower jaw D. liturosus 



(Indo-Pacific) 



4b Frontal spines 0.13-0.28 (Figure 6), slightly shorter to much longer than pectoral axil 

 spines; 12-15 S-A spines; a small downward-pointing spine below the anterior margin of 

 the eye absent (Indo-Pacific specimens) or present (most Atlantic specimens); dorsal 



blotches without a distinct light border; no gular band D. holocanthus 



(circumtropical) 



541 



