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Conus significatus (Nomura, 1935)
Descrizione (1).
Shell medium in size, obconical: test moderately thick. Spire very low; apex acute, decidedly concave in general outline. Whorls 12, apical ones embryonal, smooth and globular; post-embryonal ones shouldered and spirally striated; angle of shoulder minutely granulated on earlier whorls, more or less undulate on later ones; striae 4-5 in number, crossed by rather distinct, oblique, growth lines, making surface appear more or less granular. Body-whorl large, outline straight, peripheral angle acute; spirally grooved throughout; grooves about 45, rather unequal, wider on lower part than on upper. Outer lip fractured; aperture apparently narrow, straight, parallel sided as in C. sieboldi.
One specimen; 47 mm. in height, 22 mm. in diameter, and 42 mm. in the length of aperture.
Compared with the preceding species, this shell has a spire less elevated and more concave in outline; revolving grooves and ridges are more extensively marked upon its body-whorl. C. decollatus martin from the Neogene of Java somewhat resembles the Formosan fossil, but differs in its much smaller shell with a different sculpture.
Fossil occurrence: Byoritu Beds.—Wangwa: station 24; Reg. No. 52394.
Pliocene, Taiwan.
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Bibliografia
