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Conus cercadensis (Maury, 1917)
Conus kitteredgei (Maury, 1917)
Conus porcellus (Pilsbry & Johnson, 1917)
Description of Conus cercadensis (2)
Shell
short, broad, solid, ficiform; nuclear whorls two; first four
post-nuclear whorls with a well-defined, slightly overhanging carina
; subsequent four or five whorls broadly channeled, the channeling
being most apparent on the summit of the last whorl; spire with
no trace of spiral striae, but sharply marked by
arcuate growth-lines; body whorl markedly convex below the
shoulder carina, giving the shell its characteristic fig-shaped
form; the sculpture of the last whorl consists of a varying
number of spiral ridges, strongest anteriorly, fading out more
or less posteriorly; some adult shells have the upper half of the
body whorl nearly or quite smooth, while in others it is striate
to the shoulder; aperture rather wide, posterior sinus deep. The
relative proportion of breadth to height varies as follows: 27x16,
28x18, 29x20, 35x23 mm.
Our specimens are identical with some labelled by Gabb C. cedonulli? , but they are not the true C. cedonulli of Hwass.
Locality.
— (Exp'd '16) Bluff 3, Cercado de Mao. (Abundant and
characteristic).
Conasprella cercadensis and C. kitteredgei (Maury, 1917) have similar overall shell morphologies, but their preserved coloration patterns exhibit subtle differences: C. kitteredgei shows evidence of axial streaks and spiral dashes on the last whorl, in addition to dots on the sutural ramp, none of which are observed in C. cercadensis. Both taxa appear to be closely related to the Recent western Atlantic species C. puncticulata (Hwass in Bruguière, 1792) (Fig. 7I,J), which—with its axial streaks and rows of discontinuous spiral lines—has a coloration pattern that is most similar to that of C. kitteredgei. Conasprella puncticulata is the sister species of C. perplexa (Sowerby II, 1857), a Recent eastern Pacific taxon. Tucker and Tenorio assigned both C. cercadensis and C. kitteredgei to the genus Perplexiconus Tucker and Tenorio, 2009, which was considered by Puillandre et al. a synonym of Ximeniconus Emerson and Old, 1962, a name that they applied at the subgeneric level and which is followed here (4).
Description of Conus kitteredgei (2)
Shell with a short, acute, very concave spire, one-seventh the length of the shell, which is less than twice the width; earliest two post-nuclear whorls faintly crenulate, the following three of the spire and on the last becomes well marked; spiral striae absent, the spire being smooth except for arcuate growth-lines; convexly to a rather broad base; upper two-fifths of the last whorl typically nearly smooth, showing only faint, obsolete ridges; aperture wide; outer lip sharp; posterior notch deep.
Length of the shell 31, greatest width 17 mm.
We have specimens with the ridges extending almost or quite to the shoulder of the body whorl (fig. 6). These appear to be a variety. They were found in the same zones as the typical shells.
This species is closest to C. cercadensis, from which it can be distinguished by the concave spire and the much less convexity of the body whorl below the shoulder. They were analogous species, C. cercadensis being characteristic of the Mao and C. Kitteredgei of the Cana Rio. I take great pleasure in naming this species in honor of Mr. and Mrs. Kitteredge of Hastings-on-the-Hudson.
Localities. — (Exp'd ' 19) Zones H and I, Rio Cana at Caimito.
Description of Conus porcellus (3)
The shell is broad, the diameter about two-thirds of the length. The spire is low-conic with slightly concave outlines, composed of about 10 whorls, the later two or three concave above, earlier ones flat, a few showing a slightly projecting angle above the suture; lightly sculptural with arcuate growth-lines. The shoulder of the last whorl is well rounded; lateral slope convex in the upper part, then straight. A siphonal fasciole is defined by an oblique, spiral ridge, below which there are four spiral curds. Above the ridge there are about 10 narrow, widely spared spiral cords, each bordered above by a slight gutter which id striated vertically. The upper third of the last whorl is nearly smooth, but muter a lens it, shows faint, widely spaced spirals, either slightly raised or indicated by gray lines.
Length 29.3, diam. 19 mm.; length of aperture 25 mm. (type).
" 38.0, " 24 " (largest specimen)
Type No. 2510.
A series of several hundred specimens in the collection, the type being contained in No. 2550, A. N. S. P. We are utterly at a loss to account for Clabb's reference of the shell to C. cedonulli, which is entirely different.
The sculpture is rather variable, as usual in Conus some individuals showing raised spirals nearly up to the shoulder, while in other the upper half may be smooth.
The authors have had a revision of the fossils of Santo Domingo and Haiti, chiefly contained in the William M. Gabb collection, in preparation for some years. The work is now completed; but as some months must elapse before the illustrations can be published, advance deseriptions are here given of most of the new forms. The age of the Santo Domingan beds covered by the collections of Heneken and Gabb has been the subject of some uncertainty; but it appears that the lower bed or beds, containing Orthaulax, are nearly or quite equivalent to the Orthaulax pugnax zone of the Oligocene of Tampa Bay, while the upper beds, furnishing most of the fossils, are uppermost Oligocene, synchronous with the upper beds (Gatun formation from 12 to 8.5 Ma ) of the Canal Zone.
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Bibliografia
Consultata
