Notobranchaea valdiviae Meisenheimer, 1905c
Overview
This is a small naked pelagic snail, up to 0.6 cm long, with an opaque body, the visceral organs may be seen through the body wall. The anterior tentacles are small and there are no buccal cones. The posterior gill has three well developed crests. It is a good swimmer that hunts zooplankton, and lives in the Indian Ocean (Notobranchaea valdiviae).
Taxonomic Description
Head rounded, without clear neck constriction. The body is gray and more whitish anteriorly. The posterior gill with two long lateral crests, one shorter dorsal crest shows no clear fringes. The crests meet at the posterior body pole (Notobranchaea valdiviae gills). A lateral gill is absent. The median footlobe is short, while the lateral two are rather long. The laterals are only fixed to the body by their anterior most portion. Buccal cones are absent. The jaw has no central cusp but there are 7 lateral cusps at each side. There are 9 hooks, each with a broad base and curved top, in each sac (Notobranchaea valdiviae hooks and jaw). The Notobranchaea valdiviae radula formula is 6-1-6. The median plate shows a central group of small denticles and two lateral groups of somewhat larger denticles. The lateral plates have the enormous basal plates typical of this genus. A median foot tubercle is present.
Body length up to 5.5 mm.
Juveniles
A special description is not available.
Reproduction
This species is a protandric hermaphrodite.
Ecology
This species is a carnivore.
Distribution
This species is is only known from the Central Indian Ocean, see the Notobranchaea valdiviae map.
Types
Notobranchaea valdiviae Meisenheimer, 1905: 55, pl. 27, figs. 1-2, 4-7.
Holotype: not present in HMEB, u.s.
Type locality: 4°6'S 73°25'E. Coll.: CVDE, stat. 221.