Diacria rampali Dupont, 1979
Overview
This is a medium sized, pelagic snail with typical colour patterns, 0.9 cm broad. The slender shell is uncoiled but bilateral symmetrical with a long, sometimes broken off, caudal spine. The rim of the aperture and the middle of the dorsal ribs are brown. The colour pattern of the ventral lip is connected by a spot on the ventral side anterior to the lateral spines. The lateral spines are white and the lateral ribs are occasionally light brown. It feeds on small plankton mainly phytoplankton in the epi- and mesopelagic zone of all temperate and warm oceans (Diacria rampali 1).
Taxonomic Description
This is a relatively small species (Diacria rampali dorsal, Diacria rampali). The teleoconch, posterior to the lateral spines, is slender and the caudal spine is long (65% of the teleoconch length). The shell aperture is small. The rim of the aperture and the middle of the dorsal ribs is brown. The colour pattern of the ventral lip is connected by a spot on the ventral side anterior to the lateral spines (Diacria rampali line drawing). The lateral spines are white and the lateral ribs are occasionally light brown. Older specimens are slightly darker than young ones.
Shell (teleoconch) length 9.5 mm, width 9 mm, spine mark width 0.95 mm, aperture height 0.95.
Juveniles
The juvenile has a long, dorso-lateral flattened needle-like shell, with lateral sides diverging only anteriorly. The Diacria rampali protoconch I is globular. There is no sculpture on protoconch I or II. The lateral sides of protoconch II are thickened. A small ring may occur between protoconch I and II (Diacria rampali protoconch).
Reproduction
This species is a protandric hermaphrodite.
Ecology
This species is phytophagous and epipelagic. The shell is frequently covered by hydropolyps. It swims with two wings and sinks with retracted wings.
Distribution
This species shows a circum-global distribution between 40°N and 30°S in all oceans, see the Diacria rampali map.
Geological Record
This form was found in the Pliocene (Plaisancien) of the Mediterranean.
Types
Diacria rampali Dupont, 1979: 39, fig. 3.
Holotype: ZMUC. Paratypes 1 adult, 4 young specimens, ZMUC, 2 adults 6 young specimens ZMAN.
Type locality: 16°06'N 76°02'W, 300 metre wire, CDAE stat 1215iv, 27-1-1922.
Etymology: the name is given in honour of Dr. J. Rampal.