Amussiopecten churuguarensis (F. & H. Hodson, 1927)
HODSON, F., H. K. HODSON & G. D. HARRIS. 1927. Some Venezuelan, and Caribbean mollusks. Bulletins of American Paleontology, 13 (49). [p. 35, pl. 20, figs. 1, 3, 4; pl. 22, fig. 2]
1927 Pecten antiguensis churuguarensis F. & H. Hodson, 1927
F. Hodson, H. K. Hodson & G. D. Harris, 1927, plates 20, 22.
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«Shell is orbicular, inequivalve, translucent so that the internal lirae are frequently visible from the exterior. The altitude averages 50-70 mm. There are 13-14 undulating ribs which extend to the margin of each valve. The flat left valve in the younger stages has squarer ribs than the more convex valve; the flat valve tends to be a little concave in some specimens, although it is generally slightly convex. Both valves are ornamented with concentric growth lines which swing up over the rather low, undulating ribs, and down in the narrower interspaces. On each side of the interspaces, at the base of the ribs, are internal lirae, which usually are visible on the outside as radial dark lines separating the ribs and interspaces. The ears on the inflated right valve are pointed and produced above the hinge line as triangular projections on each side of the umbo. The lirae are about equally spaced in the younger stages, but on the margins of the adult shells the interspaces are a little wider than the intervals between the pairs of lirae. There is no contraction of the adjacent lirae toward the margin as mentioned in the description of P. antiguensis Brown.¹
This species is similar in some respects to P. antiguensis Brown, but does not show the tendency to become smooth towards the margin of one valve, nor do the adjacent pairs of lirae tend to contract toward the margin. The pointed ears, also, are very characteristic of our species, which is very common in its occurrence. Age: Oligocene. Locality: Districts of Petit, Miranda, Federación and Buchivacoa, State of Falcón, locality numbers 16, 30, 32, 33, 36, 40, 41, 47, 58, 59, 254, 429 (?), 489, 496, 500, 973, 1036, 1038, 1050, 1051, 1054, 1057, 1058, 1130, 1141, 1217, 1637, 1662, 1954, 1963, 1965, 1966 (?), 1987, 2002C, 2004, 2005, 2008.» ¹ Proc. Acad. Nat. Sci. of Philadelphia, 1913, p. 613, pl. 18, figs. 1-3, 5. FLOYD HODSON & HELEN K. HODSON, 1927
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