Aspects of ecology and development of Chirocephalus diaphanus Prevost (crustacea Anostraca) in the New Forest
Aspects of ecology and development of Chirocephalus diaphanus Prevost (crustacea Anostraca) in the New Forest
The natural occurrence of the fairy shrimp Chirocephalus diaphanus Prevost in two temporary freshwater ponds was investigated. There was only one generation in each wet period. There are four factors which may determine the life span. These are (a) predation, (b) low oxygen concentration, (c) temperature and (d) desiccation. The growth curve had three distinct phases. The rate of g-.covlth viaS rapid in both the first and the third phases. In the second phase the rate was very slow and may be associated with the maturing of the gonads. The maximum body length was 36 rom. The maximum life span in a predator free pond was nearly eight months o Records of the liLmology of the hro ponds for the period of the study are given. Under natural conditions the eggs sink to the bottom of the pond after laying, vlhere 1m-I oxygen concentrations exist. Eggs either develop a little ~'or no development takes place~ under these conditions. Then the eggs are exposed to moist soil when the pond dries up. This provides aerobic moist conditions which are the most favourable conditions for the embryonic development. Then hatching occurs after they are inundated vIi th rainwater. The complete escape of the nauplius from its three membranes takes place in hJO stages.
University of Southampton
Khalaf, Azwar Noaman
a72e271b-3b01-4d0f-871a-0335cd0955fc
1973
Khalaf, Azwar Noaman
a72e271b-3b01-4d0f-871a-0335cd0955fc
Khalaf, Azwar Noaman
(1973)
Aspects of ecology and development of Chirocephalus diaphanus Prevost (crustacea Anostraca) in the New Forest.
University of Southampton, Doctoral Thesis.
Record type:
Thesis
(Doctoral)
Abstract
The natural occurrence of the fairy shrimp Chirocephalus diaphanus Prevost in two temporary freshwater ponds was investigated. There was only one generation in each wet period. There are four factors which may determine the life span. These are (a) predation, (b) low oxygen concentration, (c) temperature and (d) desiccation. The growth curve had three distinct phases. The rate of g-.covlth viaS rapid in both the first and the third phases. In the second phase the rate was very slow and may be associated with the maturing of the gonads. The maximum body length was 36 rom. The maximum life span in a predator free pond was nearly eight months o Records of the liLmology of the hro ponds for the period of the study are given. Under natural conditions the eggs sink to the bottom of the pond after laying, vlhere 1m-I oxygen concentrations exist. Eggs either develop a little ~'or no development takes place~ under these conditions. Then the eggs are exposed to moist soil when the pond dries up. This provides aerobic moist conditions which are the most favourable conditions for the embryonic development. Then hatching occurs after they are inundated vIi th rainwater. The complete escape of the nauplius from its three membranes takes place in hJO stages.
Text
395047.pdf
- Version of Record
More information
Published date: 1973
Identifiers
Local EPrints ID: 467175
URI: http://eprints.soton.ac.uk/id/eprint/467175
PURE UUID: b9ebf4a0-86fb-453c-8b6a-9befce588364
Catalogue record
Date deposited: 05 Jul 2022 08:15
Last modified: 16 Mar 2024 21:02
Export record
Contributors
Author:
Azwar Noaman Khalaf
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics