12 BULLETIN ISO, UNITED STATES NATIONAL MUSEUM 



Family OPHICHTHYIDAE 



KEY TO THE OPHICHTHYID EELS FROM THE PHOENIX AND SAMOAN ISLANDS 

 IN THE NATIONAL MUSEUM 



la. Origin of dorsal before gill openings, usually in front half of head ; posterior 

 nostrils below front of eye in upper lip and directed downward ; tip of lower 

 jaw barely reaching to rear base of tubular anterior nostrils, which are on 

 under side of snout. 

 2a. Pectorals developed, as long as or longer than diameter of eye; teeth 

 granular, in two rows on dentary and intermaxillary plate, also two 

 rows anteriorly on maxillary and vomer, forming a single row posteri- 

 orly Myrichthys Girard 



3o. Color pattern consisting of about 26 to 30 black rings that completely 

 encircle trunk and tail and extend on dorsal and anal fins; greatest 

 width of dark bar at gill opening, is contained 0.9 to 1.9 times in 

 width of next pale interspace; there may or may not be round black 

 spots between dark bars that encircle body mostly posteriorly; anus 

 occurs at the twelfth to fifteenth black ring. Following proportions 

 indicate shape of this eel: Head 18 to 20; depth 48 to 62; tip 

 of snout to anus 2.1 to 2.2, all in total length. Eye 1.9 to 2.2 

 in snout. Depth 2.5 to 3.3; tip of snout to origin of dorsal 2.0 to 

 2.3 ; tip of snout to rictus 3.7 to 4.0 ; length of snout 5.5 to 0.5 ; length 

 of pectoral 17 to 28 ; end of dorsal fin to tip of tail 1.2 to 1.7 ; all in 

 length of head. Anal fin gradually disappears some distance in advance 

 of rear end of dorsal fin. Teeth as in figure. 



Myrichthys colubrinus (Boddaert) 

 3&. Color pattern consists of about 47 or 48 pairs of alternating black spots 

 as counted along dorsal half of body ; black spots are smaller ven- 

 trally. Following proportions indicate sh.-ipe of this species : Head 14 to 

 18 ; depth 39 and 44 ; snout to anus 2.4 and 2.5, all in total length. Eye 

 1.5 in snout. Depth 2.6 and 2.8 ; tip of snout to dorsal 16.4 and 16.5 ; 

 snout to rictus 3.3 and 3.5 ; snout 5.2 and 5.7 ; rear end of dorsal fin to 

 tip of tail 4.6 to 7.2; length of pectoral 9 and 10.8; all in the head. 



Teeth as shown in figure Myrichthys maculosus (Cuvior) 



Be. Color pattern consisting of about 28 to 31 black rings that do not 

 completely encircle trunk and tail, these rings not nearly meeting 

 along ventral side but extending on dorsal fin ; greatest width of 

 dark bar or ring at gill opening is contained 2.5 to 4 times in 

 width of next pale interspace; there may or may not be large 

 round dark spots between blackish body rings; proportional meas- 

 urements essentially same as for Myrichthys coluhrinus. 



Myrichthys semicincta (Bleelcer)'" 



21). Pectorals undeveloped, gill openings somewhat ventral in position; teeth 



caniuelike or conical, in one series on maxillary and dentary, and in one 



or two rows on vomer, and one median tooth followed by a pair of 



similar conical ones on intermaxillary plate Callechelys Kaup 



4a. Color pattern of a single wide band along middle of body with pale 

 above and l)olow it ; margin of dorsal blackish iintil two head 



'» This speoics is distinct from M. coluhrinufi, and acrnin Blooljor must receive credit for 

 havin.cr distinguished the three forms of this type of eel, tlirown together by Fowler and 

 others in recent years. 0;;/(j.s»r((.s- fnxcintus var. latifasciatn r.l'eel«>r (.\tlas ichtiiyoloffiii'ie 

 . . ., vol. 4, p. 64. pi. 1C.5. fig. ]. 1864) is the species currently recognized with the \Yide 

 blacl; bands around the body and here called M. coluhrinus. The other form, Ophisurus 

 fasciatus var. oculata Bleeker. Ii;is narrow bands around the body and is undoubtedly the 

 species described by Fowler as C'/f^cros/f.s clops (Proc. -Acad. Nat. Sci. Philadelphia. 1012. 

 p. 13, fig. 3. and Fishes of Oceania, fig. lOL All specimens of If. semicincta (Blocker) 

 observed by me come from the Palmyra Islands. 



