|
Class Neritaemorphi Koken, 1896
Order Neritoidea Rafinesque, 1815
Family Neritidae Rafinesque, 1815
Genus: Clithon, Montfort 1810
Species: Clithon sowerbyana , Reculez 1842
Description:
Shell:
- spherical, ovoid, matte with pronounced growth lines
- apex often corroded, hidden by the next-to-the-last whorl.
- pattern and coloration variable
- yellowish green or olive-colored basic coloration, sometimes with red and white speckles
- Typical: intermittent black bands
- Aperture and septum: ash-colored to blueish-white
- Operculum: - greyish with a red line
- Size: - 13 – 16.5 mm, height 13 - 16 mm
MARTENS (1879) classified four color variants:
- Polysticta: White and red speckles, red color, sometimes shading off into black
- Lactiflua: yellow-white radial lines, sometimes on reddish or green-grey ground, the lines are very often interspersed with a zone of dots/speckles
- Maculafasciata: black longitudinal bands, with yellow-white dots/speckles
- Interruptis: black bands interrupted by white-yellowish lines,with yellow or red areas, speckled or banded
Range, habitat:
- Japan, China, Taiwan, Philippines, Indonesia, Malaysia and Thailand.
- It lives on sandy or rocky ground, mostly in brackish-water areas.
- It can mostly be found in lagoons and estuaries of small rivers.
- Tropical climate: 25 – 32 °C
Case study, parameters measured by Starmühlner
From fresh to sea water:
Temperature El. Conductance value pH Total Hardness (Na-ions) (Cl--ions)
27.3°-30° C 233-401 \i Siemens 7.4-7.6 3.6°-^° dH (1750 mg/1 3360 mg/1)
(bW: up to 9500 n Siemens ) (brackish water : up to 50° dH)
Development and Reproduction:
- disecious, no external distinguishment possible
- female attaches whiteish, hard, ovoid egg cocoons to various substrates
- from the eggs, veliger larvae hatch and wander from freshwater to brackish areas and from there on into the sea.
- On their journey back the veligers develop into snails.
- Thus reproduction in the tank should be impossible.
- There are no data about their life span. Individual specimens have been kept in a tanks for three years or longer.
Food:
- incessantly grazes on hard substrates (hard green algae)
- burrows in muck and eats there.
- Seems to eat powdered food, with a high vegetable protein content.
Socialization:
- It is not very vulnerable to attacks and can thus be kept together with various fish species. Dwarf shrimp and other gastropods with the exception of Anentome helena are unproblematic.
- They should be kept in small groups as they like company.
- Unobtrusive worker, only leaves the water when about to starve or when massively bothered in the tank.
- The tanks should have algae when this snail is put in, as these wild-caught gastropods do not eat artificial food at first.
Sources:
- Archiv für Molluskenkunde der Senckenbergischen Naturforschenden Gesellschaft, Band 105 Rolf A.M. Brandt, 1974
- The Freshwater Gastropods of the Andaman-Islands By FERDINAND STARMÜHLNER ' 1976
- University of Florida Malacology database www.conchology.be
- listserv.uga.edu Enterprise Information Technology Services The University of Georgia
- Taxonomy and Distribution of the Neritidae (Mollusca: Gastropoda) in Singapore Siong Kiat Tan, Reuben Clements
- Freshwater Molluscan Shells by Martin Kohl
Author: Alexandra Behrendt
Translator: Ulrike Bauer
This page was actualized on November 12, 2008
|
