Cavolinia gibbosa (d'Orbigny, 1836) forma flava d'Orbigny, 1836
Overview
This is a globular shelled pteropod, about 0.5 cm long. The transparent shell is reddish. The lateral spines are small, the caudal spine is pronounced as is the upper shell lip. The ventral side is vaulted, width is <70% of the length. A Cavolinia g. flava adult specimen in the colour photo shows the reddish colour of the shell. It lives in the surface layers of the Atlantic Ocean, and is a phytophagous mucus feeder.
Taxonomic Description
Hyaline shell with dark brown colour patches, lateral spines curved slightly caudad, the long caudal spine is curved strongly dorsal. The shell aperture is narrow, on the ventral surface a faint hammered structure is found. The shell is not as thick as in Cavolinia g. gibbosa, see the Cavolinia g. flava drawing. In young specimens of Cavolinia g. flava the body is relatively small. The Cavolinia g. flava radula formula is 1-1-1.
Shell length varies between 3.5 and 5.0 mm, its width varies between 3.0 and 4.5 mm.
Juveniles
A special description is not available.
Reproduction
This species is a protandric hermaphrodite.
Ecology
This species is phytophagous.
Distribution
This forma is found in the NW-Atlantic Ocean, see the Cavolinia g. flava map. It occurs subfossil in the Mediterranean where its first occurrence is from Holocene age (9000 BP) (Corselli and Grecchi, 1987).
Types
Hyalaea flava d'Orbigny, 1836: 97 (1846) pl. 5, fig. 21-25.
Holotype: BMNH 1854.12.4.13, 2 fragm. of one spec. (dry collection) u.s.
Type locality: Pacific Ocean 30°S 92°E. Coll.: CVAM.