Euvola perula (Olsson, 1961)
OLSSON, A. A. 1961. Mollusks of the Tropical Eastern Pacific, Particularly from the southern half of the Panamic-Pacific Faunal Province (Panama to Peru). Panamic-Pacific Pelecypoda. 574 p., pls. 1-86. Paleontological Research Institution. New York , USA. [p. 158, pl. 20. figs. 3-3c; pl. 21, figs. 3, 3a]
1961 Pecten (Pecten) perulus Olsson, 1961
A. A. Olsson, 1961, plates 20, 21.
|
«The shell is small or of medium size, seldom exceeding 40 mm. in height, thin. The right valve is strongly convex, its curvature nearly that of a half circle whose greatest convexity lies just above the middle, the surface of the umbone sloping downward to an appressed beak. Ribs of the right valve number about 22, almost obsolete near the beak, strengthening across the middle zone and generally mesially grooved on the ventral portion, their interspaces concave and flattened. The left valve is smaller, rather deeply depressed or flattened in the middle, its lateral submargins elevated, flaring and smoothish. Ribs on the left valve are fewer in number, usually 17 or 18; these are narrow, simple above, widening a little ventrally and separated by much wider interspaces, each of which generally carries an intercalary riblet. Surface of both valves, if well preserved, is uniformly covered with close-set, raised concentrics which loop up and down across the ribs and their interspaces. In the interior, the external ribbed sculpture is shown in the reverse, mostly around the margin but the flutings of the ribs are shallow and do not indent the margin. Color of the valves is mostly wine-red, the umbones, especially of the right valve much lighter, sometimes white. Left valve is generally maculated more strongly than that of the right. The interspaces on the right valve generally finely speckled with white dots. Interior mostly white, except in the umbonal cavity which may be yellow and for a small, narrow, colored margin in the right valve; not developed in the left.
Length 34.6 mm., height 3L5 mm., diameter 10.7 mm. double valves, length of hinge line 18 mm. Venado Beach, Canal Zone. Length 40.05 mm., height 37.8 mm., diameter 24.3 mm. right valve. Santa Elena, Ecuador. Length 38.7 mm., height 34.1 mm., diameter 5 mm. left valve. Manglaralto, Ecuador. This small species has often been confused with the much larger Pecten vogdesi Arnold and perhaps most, if not all, records of P. vogdesi from Panama southward may be based on this species. In addition to its much smaller size and lighter texture, Pecten perulus differs by its lower convexity of the right valve, its lower umbone which does not rise above the hinge margin and by its sulcated or mesially grooved ribs. The left valve differs by its wider, more flaring submargins and especially by its narrower ribs, and much wider interspaces, each carrying an intercalary riblet. Local but well distributed from Panama southward to northern Peru. Range — Panama south to northern Peru. Panama: Guanico. Canal Zone: Venado Beach. Ecuador: Santa Elena; Manglaralto; Canoa; Manta. Peru: Mancora; Caleto Mero; Lobitos.» AXEL ADOLPH OLSSON, 1961
|
«Two other extant species of Euvola occur in the eastern Pacific. One, the well-known E. vogdesi (Arnold, 1906), ranges throughout the Gulf of California and from the Pacific side of Baja California at about 28N southward to Ecuador (1S) in depths from 4 to 220 m (Bernard, 1983; Coan et al., 2000). The other, E. perula (Olsson, 1961), ranges from about 28N on the west side of Baja California (LACM 71-158) southward to northernmost Peru (4S) and extends into the southern Gulf of California as far north as Las Animas Bay (28N, USNM 818577). Depth records range from intertidal to 73 m (Bernard, 1983, and data from USNM and LACM collections).»
WALLER, T. R. 2007. The evolutionary and geographic origins on the endemic Pectinidae (Mollusca: Bivalvia) of the Galápagos Islands. Journal of Paleontology, 81 (5): 929–950, figs. 1-9. [p. 938]
|
Euvola perulus (Olsson, 1961); B. K. Raines & G. T. Poppe, 2006, A Conchological Iconography, The Family Pectinidae, plate 115.
|