Conus ancylus (Woodring, 1928)

 

 

Description (1)

 

Conus (Lithoconus) ancylus, new species (Plate 9, Figure 5)

 

Shell medium-sized, stout, crudely conical, spire moderately high. Shoulder abruptly truncated. Aperture distinctly wider at base. Siphonal notch moderately wide, shallow. Siphonal fasciole bulging. Outer lip rather strongly retractive as it approaches anal notch. Anal notch moderately deep. Anal fasciole narrow, deeply concave, bordered by shoulder, which on spire whorls forms a broad rounded ridge. Sculpture consisting of weak, obscurely beaded narrow spiral threads on anterior half of body whorl.

Length 46.6 mm.; diameter 28.5 mm. (holotype).

 

C. ancylus has essentially the same apertural features as proteus, but the anal fasciole is more concave. It is represented by three specimens, all in the Henderson collection.

At first it was identified as C. yaquensis Gabb (see Pilsbry, Proc. Acad. Nat. Sci. Philadelphia, vol. 73, p. 331, pl. 21, fig. 6, 1922; “modified” Cercado and Gurabo faunas), but the outline of the body whorl is too convex and the granulated spirals at the base of the body whorl are too numerous and too closely spaced. The type of yaquensis has a well-preserved color pattern that is the reverse of proteus.

 

C. proteus humerosus Pilsbry (Proc. Acad. Nat. Sci. Philadelphia, vol. 73, p. 332, pl. 21, fig. 4, 1922) probably is more similar to yaquensis than to proteus, but has a different color pattern.

 

I am greatly indebted to L. R. Cox, of the British Museum, for a cast of the holotype of C. solidus Sowerby (Quart. Jour. Geol. Soc. London, vol. 6, p. 45, 1850; not C. solidus Sowerby 1841). It is a young shell having a length of 39.5 millimeters and a diameter of 23 millimeters. In shape it resembles proteus, but the anal fasciole is too deeply concave. It seems to represent Gabb's yaquensis, and it is very much like a small shell from U. S. G. S. station 8739 (Rio Gurabo), though its anal fasciole is more concave. Guppy (see under C. apium) renamed this species C. recognitus, so that recognitus seems to be the name for both solidus and yaquensis. It has already been pointed out that Maury's C. “recognitus” is a pyriform species found in the Baitoa and Cercado formations.

Pilsbry's C. "recognitus" is williamgabbi Maury.

 

Two additional specimens of ancylus in the collections of the United States National Museum are incorrectly labeled Curaçao, Dutch West Indies.

 

Type material. Holotype (U. S. Nat. Mus. No. 135280).

 

 

 

 

Conus ancylus (1a)

Holotype USNM 135280

Plate 9 fig. 5

mm. 46,6 x 28,5

 

Conus yaquensis (Gabb 1873)

mm. 42,9 x 25,0

Pliocene – Tamiami Formation (Pinecrest Beds)

[AZFC N. 166-01]

Conus sewalli

Plate 5 – Fig. 3

 

 

 

 

 

 

 

 

Bibliografia Consultata

 

·         (1) - Woodring, W. P., 1928. Miocene mollusks from Bowden, Jamaica, pt. 2

·         (1a) - Miocene mollusks from Bowden, Jamaica, by Wendell Woodring