PANAMIC-PACIFIC PELECYPODA S95 



Eorytellina (EurytelUna) rnbescens (Hanley) Plate 68, f'gure 8; 



Plate 71, figures 7, 7a 



Tellina rubescens Hanley, 1844, Proc. Zool. Soc. London, p. 60. Panama and Tumbez. — 

 Hanley, 18+6, Thes. Conch., vol. 1, Tellha. p. 242, No. 38, pi. 60, fig. 153.— 

 Sowerby, 1866, Conch. Icon., vol. 17, Tellina, pi. 18, fig. 93. 



Tellina (EurytelUna) rubrserns Hanley, Hertlein and Strong, 1949, Zoologica, vol. 34, 

 pt. 2, No. 9, pp. 78, 79. 



The shell is broadly ovate, its height nearly five-eighths of its length, 

 the beaks nearly median, the side subequal, the surface color white or light 

 pink. The posterior-dorsal area is of medium width, slightly furrowed in 

 the middle and marked off by a low, umbonal angle and a slightly coarser 

 sculpture. The valves are thin in texture and of low convexity, nearly equal, 

 the posterior end not flexed or only weakly so. Surface nearly smooth and 

 glossy but on closer examination, an obscure sculpture of rather wide, con- 

 centric ribbons is seen, most heavy on the rounded anterior end, and in 

 addition much finer growth lines which often are wrinkled; also faint radial 

 striations may be present. The most characteristic feature of the species is 

 the shape of the pallial sinus whose upper limb is attached directly to the 

 anterior adductor scar. There is no lunule or escutcheon. 



Length 34.5 mm., height 22 mm., diameter 7.8 mm. Venado Beach, 

 Panama Canal Zone. 



Length 45.7 mm., height 29.6 mm., semidiameter 3 mm. Rio Chepo 

 mouth, Panama. 



This is a small or medium-sized species as indicated by the dimensions 

 above. The surface of the valves is slightly convex, nearly smooth, the 

 principal concentric sulci fading out before they reach the umbonal angle. 

 The species is easily known by the contour of the pallial sinus as shown 

 in illustration. 



Range — Mexico southward to northern Peru. Panama: Pearl Islands 

 (Rey Island); mouth of the Rfo Chepo. Panama Canal Zone: Amador 

 Beach; Venado Beach. Colombia: Isla del Gallo. Ecuador: Cojimenes. Peru: 

 Zorritos; Tumbez. 



Eurjtellina (EurytelUna) ecuadoriana (P'ilsbry and Olsson) Plate 71, figures 5-5b 



Tellina {EurytelUna) ecuadoriana Pilsbry and Olsson, 1941, Proc. Acad. Nat. Sci. Phil- 

 adelphia, vol. 93, p. 67, pi. 15, figs. 6-8.— Hertlein and Strong, 1955, Bull. Amer. 

 Mus. Nat. Hist., vol. 107, No. 2, pp. 197, 198. 



Shell elongate-ovate, rich rose-pink, glossy, the beaks nearly median, 

 the posterior side is a little longer, narrower, its dorsal margin descending, 

 straight to a narrowly subtruncated end. Ventral margin is straight in the 

 mid-zone, curved or rounded towards the ends. Valves are of s'ight but 

 nearly equal convexity, the right valve is a little depressed across the 

 middle due to a weak flexing of the ventral margin. Posterior-dorsal area 

 similar in both valves, narrow, flattened or depressed, smooth ventrally but 

 with weak radial lines showing. Sculpture consists of flat, concentric ridges 

 or narrow ribbons which are uniformly developed over most of the disk 

 except on the posterior slope, ending rather sharply at the umbonal ridge 

 especially so on the right valve. No definable lunule or escutcheon except 

 for a narrow flattening of the margin along this zone. The pallial sinus is 

 long, its upper limb somewhat sinuous, almost reaching to the anterior 

 adductor scar, and enclosing a small, triangular area between the scar and 

 its rounded off end. 



