Implications of life history for genetic structure and migration rates of southern African coastal invertebrates: planktonic, abbreviated and direct development
- Authors: Teske, Peter R , Papadopoulos, Isabelle , Zardi, Gerardo I , McQuaid, Christopher D , Edkins, M T , Griffiths, C L , Barker, Nigel P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445447 , vital:74388 , https://doi.org/10.1007/s00227-007-0724-y
- Description: The amount of genetic structure in marine invertebrates is often thought to be negatively correlated with larval duration. However, larval retention may increase genetic structure in species with long-lived planktonic larvae, and rafting provides a means of dispersal for species that lack a larval dispersal phase. We compared genetic structure, demographic histories and levels of gene flow of regional lineages (in most cases defined by biogeographic region) of five southern African coastal invertebrates with three main types of larval development: (1) dispersal by long-lived planktonic larvae (mudprawn Upogebia africana and brown mussel Perna perna), (2) abbreviated larval development (crown crab Hymenosoma orbiculare) and (3) direct development (estuarine isopod Exosphaeroma hylecoetes and estuarine cumacean Iphinoe truncata). We hypothesized that H. orbiculare, having abbreviated larval development, would employ a strategy of larval retention, resulting in genetic structure comparable to that of the direct developers rather than the planktonic dispersers.
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- Date Issued: 2007
Morphological and genetic analyses suggest that southern African crown crabs, Hymenosoma orbiculare, represent five distinct species
- Authors: Edkins, M T , Teske, Peter R , Papadopoulos, Isabelle , Griffiths, C L
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445701 , vital:74415 , https://www.jstor.org/stable/20107852
- Description: The crown crab, Hymenosoma orbiculare, occurs all along the coast of southern Africa displays great morphological variation across this range. To determine whether the species c several distinct taxonomic units, H. orbiculare were collected from 18 estuaries and lagoons Walvis Bay in Namibia and Kosi Bay in north-eastern South Africa. Open ocean individua also obtained from False Bay in south-western South Africa. Morphological and genet mitochondrial DNA) comparisons were carried out between individuals from all locatio monophyletic clusters were identified on the basis of genetic data, each confined to specific of the distribution range. Morphological data supported the distinctness of each of these clus typical H. orbiculare, characterized by large size (maximum carapace width 28 mm) and of the characteristic ornamentations of other morphotypes, occurred in estuaries and lag along the west and south coasts. False Bay deep-water individuals were of two forms.
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- Date Issued: 2007