Conus
(Leptoconus) protofurvus (Noetling, 1901)
Description (3).
The shell is of
small size, double conical in shape, being composed of a high elevated spire and a long accuminate
body whorl.
Embryonic whorls not
observed.
The high elevated spire consists of at
least six whorls, separated by a deep suture;
the surface of the whorls forms a steep angle with the suture, which does not
seem to change much with advancing age; the profile line is therefore almost straight, but slightly step-like, because each
succeeding whorl does not fully reach
up to the preceding one.
The body whorl is
high, rather narrow at its posterior end, accuminate in front. A sharp keel sets off a small
posterior part which gently slopes towards the suture from a larger anterior one, sloping in opposite
direction. About one-half to two-thirds of the surface is smooth ; the anterior half or third is covered
with deeply engraved
revolving lines, separated by broad interstices which are almost raised into ribs near the anterior end.
Stripe of growth numerous, but somewhat irregular.
Aperture long, very narrow,
outerlip thin and sharp.
Two
specimens belonging to separate species have been figured under this name in
Noetling’s second monograph. The first specimen (pl. xxiii, fig. 25) represents
the type of C. ( Leptoconus ) protofurvus, the second corresponds with
the living Conus ( Leptoconus ) vimineus Reeve (1).
Oligocene.
Yenangyrat
(Sitsayan
stage, which is in a Rupelian marine horizon (Oligocene) in the Sitsayan
Formation of Myanmar)
Remarks :
The solitary example on direct comparison with GSI Type No. 7760 of Noetling
(1901) matches so well that it is identified as Conus (Leptoconus)
protofurvus Noetling. It also resembles the drawings of Conus marginatus
J. de C. Sowerby in Noetling (1985, p. 43, pl. X, figs. 8-8b). This species is
referred to the subgenus Leptoconus due to its biconic shell (2).
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Conus
(Leptoconus) protofurvus Noetling, 1901 (Pl.
XXXVII, Figs. 8, 9) (2) Gaj
Formstion, Ashapuramata Member, Middle Miocene 2.5 km
NE of Khatumba at Ashapuramata. Sp. No.
15/419, apical and
apertural views respectively. |
Conus (Leptoconus) protofurvus (3) Tav. XXIII fig. 26b |
- (1)
- Note on the Marine Fossils collected by Mr. Pinfold in the Garo Hills.
By E. Vredenburg, Superintendent, Geological Survey of India. (With Plates
8 and 9)
- (2) - Jain (2014) "Neogene Fossils
From Kathiawar, Gujarat, India With Special Emphasis on Taxonomic
Description of Molluscs and Corals" (Courtesy of Kanishka Bose on
20/11/2023)
- (3) – Noetling (1901) “FIGURES AND
DESCRIPTION OF THE ORGANIC REMAINS PROCURED DURING THE PROGRESS OF THE
GEOLOGICAL SURVEY OF INDIA”