LEIS: SYSTEMATICS AND ZOOGEOGRAPHY OF THK PORCUPINEFISHES 



numerous. S-D spines 16-21, S-A spines 17-22. 

 Frontal spines 0.04-0.10, much shorter than pec- 

 toral axil spines. A short, fixed tribase spine im- 

 mediately above gill opening. A short, 

 downward-pointing spine below the front border of 

 eye. Five frontal spines. D 14-16, A 14-16, P 21-25. 

 Nasal tentacle normally with a pair of lateral 

 openings. Usually two small barbels on the chin. A 

 fleshy tentacle may be present over each eye. Color 

 pattern dominated by large, light-edged dorsal, 

 and dorsolateral blotches. The lateral postpectoral 

 surfaces with small spots associated with the spine 

 axils. A dark gular band starting from below the 

 eye and continuing under the chin. Fins without 

 spots except at bases. 



Description. — (27 specimens) D 14-16, A 14-16, 

 the first two rays undivided; P 21-25. Head width 

 0.33-0.42 (.r = 0.36; SD - 0.03), body width 

 0.35-0.51 Lv = 0.41; SD = 0.04); peduncle length 

 0.12-0.18 (.V = 0.15; SD = 0.01), eye 0.08-0.15 

 (X = 0.10; SD = 0.02). Dorsal, anal, and caudal 

 fins rounded, middle rays longest. Nasal tentacles 

 normally with a pair of lateral openings; occa- 

 sionally, the end of the tentacle is split, giving 

 rise to a bifid nasal tentacle without nostrils. 

 When split, the bifid arms tend to become thick- 

 ened and papillose. 



S-D spines 16-21. S-A spines 17-22, about 14 

 spine rows over the dorsum between pectoral fin 

 bases, about 26 spine rows over the ventrum be- 

 tween pectoral fin bases. Five frontal spines. 

 Longest frontal spine 0.04-0.10 ix = 0.07; SD = 

 0.02), pectoral axil spines 0.10-0.15 (.v =0.12; 



SD = 0.01). Pectoral axil spines longest on body, 

 0.40-0.78 (X = 0.61; SD = 0.09) in frontal spines. 

 Spines generally short. The only markedly elon- 

 gate dorsal spines are those above the pectoral fin 

 (ca. 0.60 in frontal spines). Frontal, middorsal, and 

 lateral (excluding pectoral axil spines) spines all 

 of about the same length. Ventral spines some- 

 what shorter (ca. 1.3 in frontal spines I. The spines 

 of the interorbital region and nape often reduced 

 or buried, especially in individuals larger than 

 150 mm, but, in any case, shorter than frontal 

 spines. The shaft extension is variably developed, 

 its size positively correlated with the size of the 

 lateral bases. No spines on caudal peduncle, but 

 along the base of both dorsal and anal fins there is 

 a spine whose shaft extends onto the peduncle. In 

 two of the specimens examined these spines were 

 on the peduncle, but they were still clearly as- 

 sociated with the fin bases. A short, fixed tribase 

 spine immediately above the pectoral base. Three 

 short, flat spines with broad lateral bases form the 

 anterior border of the gill opening. A short, 

 downward-pointing spine below the anterior bor- 

 der of the eye. 



Two small barbels on the chin. A fleshy tentacle 

 above each eye present in about one-third of the 

 specimens. Rarely, a more extensive set of tenta- 

 cles along the ventrolateral edge of the body simi- 

 lar to that described for D. holocanthus . 



Background color in preserved specimens varies 

 from dark brown to light buff. The color pattern is 

 dominated by several large dark brown to black 

 blotches on dorsal and lateral surfaces. These 

 blotches edged in a color lighter than background 



FIGURE \5.—Diodon liturosus. 142 mm SL, Ko Samet, Thailand (CAS 30967). 



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