FISHES OF THE PHOENIX AND SAIVIOAN ISLANDS 71 



Order THORACOSTEI 

 Family SYNGNATHIDAE 



KEY TO THE PIPEFISHES FROM THE PHOENIX AND SAMOAN ISLANDS AS 

 REPRESENTED BY SPECIMENS IN THE NATIONAL MUSEUM ^ 



Ir;. Caudal fiii absent, tail prehensile ; pectoral present ; egg pouch of male in 

 front of anal fin ; body depressed with narrow dorsal sui-face and the 

 ventral surface much broadened ; dorsal 40 ; rings 17+50 ; pectoral 22 ; 

 anal 5 ; ix)Storbital length of head twice in snout ; eye 4 in snout. 



Syngnathoides biaculeatus (Bloch) 

 16. Caudal fin present, tail not prehensile; anal fin present. 



2a. Superior cristae of trunk and of tail discontinuous ; operculum with a 

 keel either confined to base of operculum or extending along its entire 

 length ; base of dorsal fin not elevated. 

 3a. Trunk rings more numerous than tail rings numbering lS+14 to 16; 

 dorsal rays 25 to 2S; anal 3 or 4; pectoral 20 or 21; egg pouch iu 

 front of anal fin; caudal fin IV^ times in head; length of caudal fin 

 equal to snout and eye ; median cristae of trunk continuous with 

 inferior cristae of tail ; inferior cristae of trunk ending on last 

 trunk ring; superior cristae of trunk ending on next to last ring 

 along dorsal fin base ; color brown ; on a specimen 52 mm. in stand- 

 ard length a black band extends from snout through eye, thence 

 along side of body ; tail fin blackish posteriorly, the basal Vi white, 

 margin of fin white, and a white area or spot in center of caudal 

 fin posteriorly ; middorsal line of snout with four or five small blunt 

 spines then a space and four or five more; anterior half of inter- 

 orbital space wiih a double ridge, the edges serrated 



Doryrhamphus melanopleura (Bleeker) 

 3&. Trunk rings about equal to or much fewer in number than tail rings. 

 4a. Trunk rings about 21+22 to 24; dorsal rays 39 or 40; anal 3; pectoral 

 21; anus closer to base of caudal fin than pectoral fin base; most 

 of dorsal fin on tail rings; median cristae of trunk continuous 

 with inferior cristae of tail, inferior cristae of trunk subcontinuous 

 ahnost continuous with inferior cristae of tail ; postorbital part of 

 head 2^/2 times in snout; eye 4i/4 to 5 in snout; ridges on head 

 not serrated, but keels of rings rough ; egg pouch of male abdominal 



Doryichthys brachyurus (Bleeker) 



4&. Trunk rings numbering about or at least half as numerous as tail 



rings, 15 or 16+30 to 40. 



5o. Tail rings with median cristae; egg pouch in front of anal fin; anus 



much closer to base of pectoral than base of caudal fin, the 



distance from base of pectoral to anus 1% in tail ; dorsal mostly 



on tail rings; rings 10+31 or 32; dorsal rays about 33; pectoral 



17 or 18 ; anal 3 ; postorbital part of head about equal to snout ; 



eye twice in snout; ridges of head smooth; median cristae of 



trunk continuous with inferior cristae of tail; caudal fin equal 



to postorbital part of head Doryichthys retzii (Bleeker) 



56. Tail rings without median cristae; egg pouch of male behind anal 

 fin ; dorsal fin mostly on tail rings. 

 6«. Snout shorter than postorbital part of Iiead and with a mid- 

 dorsal serrated keel ; keel on opcrcle confined to its base ; supra- 

 « Modified after Weber and De Beaufort, 1922. 

 424599—42 G 



