ROSENBLATT and BUTLER: THE RIBBONFISH GENUS DESMODEMA 



with rear end of pectoral base. Orientation of fin 

 bases and shape of rays as described for D. lorum. 

 Pelvics frayed in all specimens, but reaching 

 beyond end of caudal in one and to caudal base in 

 another. 



Color in alcohol pale, with a dusky area above 

 and behind head, extending over forehead and an- 

 terior to snout tip. Ventral parts of head dusky, a 

 dark streak below eye, running down behind 

 maxilla, a dusky streak along throat to pelvic 

 base. Body with conspicuous black spots which are 

 somewhat larger and more widely spaced poste- 

 riorly and above midline. No spots conspicuously 

 larger than others. A narrow dark streak on back 

 along dorsal base, running out to caudal base. 

 Probable life colors, based on two frozen speci- 

 mens, silver with black spots; iris silver and the 

 dorsal and caudal red; pectorals with pink tinge. 

 This coloration corresponds well with that of the 

 figure given by Tanaka (1908) except that the iris 

 is shown by him as green. Smaller individuals 

 differ (our smallest 32 mm SV) mainly in that the 

 body is less deep and the ventral profile nearly 

 straight, and there are no polka dots. The 37.5-mm 

 SV holotype of T. deltoideus was described as "uni- 

 form bright silvery." A 55-mm SL individual in 

 poor condition has traces of spots. 



Remarks. — Leapley (1953) figured and de- 

 scribed a Florida specimen of D. polystictum under 

 the name Trachipterus trachyurus Poey 1861. The 

 identification was based on the presence of 76 dor- 

 sal rays in Leapley's specimen, Poey's specimen 

 having been reported to have 82 dorsal rays. 



Leapley's photograph is of a Desmodema with a 

 large eye and a relatively deep tail, in agreement 

 with D. polystictum. No vertebral counts were 

 given, but Frank Schwartz (pers. commun.) has 

 supplied vertebral counts for Leapley's specimens, 

 as well as an additional individual from the west- 

 ern North Atlantic. Both have 18 precaudal ver- 

 tebrae, also in agreement with D. polystictum. 



If Leapley's identification were correct, Poey's 

 name would be a senior synonym of Desmodema 

 polystictum (Ogilby 1897). However, three charac- 

 ters indicate that D. polystictum cannot be iden- 

 tified with T. trachyurus. These are number of 

 ventral rays (6 in trachyurus, 8 or 9 in polystic- 

 tum), pectoral rays (15, vs. 12-14), and coloration 

 (silvery with a midlateral yellow band vs. polka- 

 dotted). In addition, T. trachyurus was described 

 as having vertebral processes piercing the skin 

 (probably an artifact caused by postmortem dry- 



ing) and lacking elongated anterior dorsal rays 

 (present in all juvenile trachipterids). 



The supposed agreement in low number of dor- 

 sal rays is invalid, since Leapley's specimen was 

 broken far in advance of the caudal. Using his 

 value for body depth of his specimen (141 mm) we 

 estimate the actual length to have been between 

 1,400 and 1,500 mm. Poey's description does not 

 allow the identification of T. trachyurus with any 

 known trachipterid. Zu cristatus is excluded be- 

 cause juveniles of that form are strongly barred 

 and have peculiar fleshy abdominal lobes that are 

 unlikely to go unmentioned in a description. 



The species of Trachipterus are not completely 

 understood, but juveniles of that genus have dark 

 markings, a dorsal pennant, and tubercles along 

 the venter. 



Material examined. — Western and Central 

 Pacific: CAS SU 23783, Sagami Bay 1(72.8, 102.5); 

 CAS 5532, Rurutu, Tubuai Islands 1(37.5, 49.9), 

 holotype of Trachipterus deltiodeus. Eastern 

 Pacific: UCLA W58-103, 96 km southwest of Cabo 

 San Lucas, Baja California, tuna purse seine, 2(66, 

 91 and 88, 125); SIO 70-142, 19°50'N, 106°15'W, 

 tuna purse seine, 1(260); SIO 68-33, 19°53'N, 

 1 10°46 ' W, "5 x 5" nekton net towed at 5 knots, 800 

 m wire out, 1(333, 1,040); SIO 63-915, 16°01.5'N, 

 100°54'W, "5 x 5" nekton net, 0-200 m, 1(277, 

 785); SIO 76-167, 12°55'N, 90°54'W, tuna purse 

 seine, 1(111.5); SIO 76-294, 12°35'N, 92°15'W, 

 tuna purse seine, 1(84.9, 126.5); SIO 76-67, 

 12°15'N, 92°25'W, tuna purse seine, 1(42); UCLA 

 W67-135, 11°48'N,88°25'W, 1(60 SL); SIO 73-392, 

 11°18'N, 91°31'W, tuna purse seine, 1(91.5); SIO 

 75-139, 10°00'N, 119WW, midwater trawl, 0-50 

 m, 2(74.3, 100.5 and 90 SL); SIO 76-325, 10°24'N, 

 107°46'W, midwater trawl, 225 m wire out, 

 1(25.5); SIO 73-400, 08°41'N, 85°03'W, dipnetted 

 at surface, 1(82); SIO 64-397, 03°18.4'N, 

 101°54.3'W, stomach of Alepisaurus ferox 1(55.5); 

 SIO 63-299, 04°03'N, 80°46'W, meter net, 400 m 

 wire out, 1(23); SIO 75-590, 00°00.2'S, 

 119°17.0'W, meter net, 0-200 m, 1(28.0, 36.0); SIO 

 52-334, 02°47'S, 112°13'W, meter net, 0-250 m, 

 1(29, 40.5); SIO 73-340 "Eastern N. Pacific," tuna 

 purse seine, 1(296, 835). 



Desmodema lorum n.sp. 



Figures 3, 4, 5, 6 

 Desmodema polysticta, not of Ogilby. Fitch 



851 



