Conus washingtonensis   (Van Winkle 1918)

 

 

Description: Shell minute; spire high, averaging between two-thirds and three-fourths of the length of the body whorl; whorls seven to seven and a half in number; suture linear and appressed; on the middle of the surface of each whorl, just above the shoulder, there is a revolving groove; between the groove and the suture there is a convex revolving fold. Ornamentation of the shell consists of very faintly developed flat topped revolving ribs with interspaces of equal width; outer lip thin; inner lip without callous; aperture narrow. This species differs from Conus ruckmani Dickerson, in the constancy of the greater length of the spire and in the entire absence on all specimens of nodes on the shoulder of the whorls (1).

 

Dimensions Altitude of shell 3.5 mm.; altitude of spire 1 mm.; maximum diameter of shell 2 mm.; angle of spire 60.

 

Occurrence At locality 330 (University of Washington Paleontological Collection) situated at the Greece ranch, four miles east of Vader, on the east bank of Cowlitz River, in Section 25. Township 11 North, Range 2 West.

 

Horizon Lower Oligocene; lower phase of Molopophorous lincolnensis Zone.

 

 

E’ una conchiglia minuta; la spira è elevata ed occupa in media 2/3 – ¾ dell’intera altezza della conchiglia. Le spire sono in numero di 7 – 7½; la sutura è lineare e depressa. In mezzo alla superficie di ciascuna spira, proprio sopra alla spalla, si trova una linea spirale: tra questa linea e la sutura la superficie è convessa. La superficie della conchiglia è ornata con piccoli rigonfiamenti separati da spazi della medesima dimensione.

 

 

 

 

 

Conus washingtonensis

Plate VII, fig. 9

mm. 3,5 x 2,0

 

Località 330 (Greece ranch, 4 miglia ad est di Vader)

Chehalis Valley, Washington

Lower Oligocene

 

 

Conus washingtonensis

Holotype CAS-GEO 7540.00

 

 

 


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