Conus
(Hemiconus) lateralis (Tracey et al.,
2017)
Descrizione e caratteristiche (1):
Diagnosis of H. lateralis n.
sp. : Small, broadly biconical Hemiconus,
with a smooth profile and angular shoulder. Lacking subsutural beads (1).
Description of H. lateralis n.
sp. : Shell small, spire 32% of shell height ;
protoconch large, diameter 645 μm., paucispiral of 1.75
whorls ; Spire whorls flatsided, slightly extraconic at first, with a narrow
row of nodules imbricated over the lower suture, and a more or less smooth
subsutural collar ; upper part of whorl initially almost smooth, developing c.
5 weak, spiral threads on later whorls ; peripheral nodules divided by a
central sulcus on the last whorl, where they deteriorate to form a weakly
nodular shoulder overridden by a double spiral cord. Last whorl covered in
close, rounded spiral cords becoming more prominent towards the base. Sinus
wide and shallow, aperture narrow with parallel sides ; columella straight,
outer lip gently curved. Up to 10.8 x 5.4 mm (1).
Discussion of H. lateralis n.
sp.: The broad biconical aspect of the shell,
flattened whorl profile and subdued ornament are quite different from most Hemiconus
and recall the shapes of some living Conidae. However, the double
perphiperal cord and vestigial subsutural collar link it to Hemiconus. This
species most closely resembles H. tremletti Le Renard, 1994 but differs
in having no beads on the subsutural cord, a larger protoconch and a narrower
row of nodules placed lower on the spire whorls, becoming a narrow double cord
crossing the nodules on the last whorl. It differs from H. auriculatus n.
sp. by its smooth profile, lower and less prominent nodules and greater breadth (1).
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Figs. 85 – 86. Hemiconus lateralis n. sp. 85a-d. Holotype (85c protoconch, 85d apical) NHMUK PI TG
26914 (leg. S. TRACEY) Fresville 86. Paratype NHMUK PI G 15573(1)
(coll. PISSARRO as Conus parisiensis) Fresville |
Bibliografia Consultata