Considering South Africa’s richness in aquatic species, very little knowledge exists
regarding copepods that are symbiotic on hosts ranging from invertebrates to marine
mammals. In order to have any indication of the existing biodiversity of this group of
organisms in South African waters, a thorough investigation of all possible hosts
needs to be conducted, which in turn will most likely increase the number of
recorded symbiotic copepods considerably. The current descriptive study was done
in an effort to contribute to a larger study of metazoan parasites of elasmobranch
hosts along the KwaZulu-Natal coast of South Africa. A total of 40 (31 Mobula kuhlii;
two Mobula eregoodootenkee and seven Manta alfredi) mobulids were examined for
infection by symbiotic copepods at the KwaZulu-Natal Sharks Board (KZNSB). More
than 90% of all examined hosts were infected with different types of symbiotic
siphonostomatoids. Collected copepod specimens were fixed and preserved in 70%
ethanol and studied with both the stereo- and light microscopes using the wooden
slide technique. Some selected specimens were further studied using Scanning
Electron Microscopy (SEM) to elaborate on ill-defined features. A total of 13 different
species of the order Siphonostomatoida distributed over five families were identified.
The five families include Eudactylinidae (Eudactylina oliveri, Eudactylina diabolophila
and Nemesis sp.); Caligidae (Caligus crysophrysi, Pupulina sp. 1, Pupulina sp. 2;
Pupulina sp. 3, Unidentified sp. 1, Unidentified sp. 2 and Unidentified sp. 3);
Kroyeriidae (Kroeyerina mobulae); Dichelesthiidae (Anthosoma crassum) and
Cecropidae (Entepherus laminipes). Two of the 13 species (E. laminipes and A.
crassum) are monotypic and were therefore easily identified. Eudactylina oliveri
exhibited a prevalence of 75% and 100%; mean intensity of 42 and 130 parasites
per host and a mean abundance of 32 and 130 individuals per host while Pupulina
sp. 1 exhibited a prevalence of 61.29% and 100%; mean intensity of 41 and 5
individuals per host and a mean abundance of 2 and 5 individuals per host on M.
kuhlii and M. eregoodootenkee respectively. Component populations of E. oliveri and
Pupulina sp. 1 exhibited an aggregated distribution pattern on their examined hosts.
The phylogenetic relationship between nine caligid species (three known Pupulina
species, three collected Pupulina species and three Unidentified sp. species as ingroup)
with Caligus glandifer as out-group was determined and analysed using a
morphological dataset (40 characters) from previous and current descriptions. The
ii
exhaustive search with PAUP* retained a single most parsimonious tree with a tree
length (TL) = 85; consistency index (CI) = 0.7; retention index (RI) = 0.7; homoplasy
index (HI) = 0.3 and a rescaled consistency index (RCI) = 0.5. Bootstrap support for
the estimated clades was mostly low with values less than 95%. The phylogenetic
hypothesis of the 10 caligid species presented in the current study was derived from
the phylogenetic analysis of the information for adult females and is therefore not
intended to be a definitive theory but should be treated as a testable hypothesis that
can be further analysed using more data. The current study provides the first record
of C. chrysophrysi, Pupulina sp. 1, Pupulina sp. 2, K. mobulae and E. laminipes on
M. kuhlii; E. oliveri, Pupulina sp. 1, Pupulina sp. 2 and Pupulina sp. 3 on M.
eregoodootenkee; and E. diabolophila, Nemesis sp., C. chrysophrysi, E laminipes, A.
crassum and the three Unidentified species on M. alfredi frequenting the east coast
of South Africa and thus contributes to the knowledge of our marine biodiversity.
Mobulid hosts were not carefully studied for copepod infection previously and the
copepods that were reported from the mobulids were probably found by chance.
Therefore future investigation into the symbiotic siphonostomatoids of more mobulid
hosts and other host species may result in more reports of symbiotic Copepoda from
South African waters. / Thesis (MSc. (Zoology)) -- University of Limpopo, 2013
Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:ul/oai:ulspace.ul.ac.za:10386/1006 |
Date | January 2013 |
Creators | Lebepe, Modjadji Concelia |
Contributors | Dippenaar, S. M. |
Source Sets | South African National ETD Portal |
Language | English |
Detected Language | English |
Type | Thesis |
Format | xiv, 164 leaves : ill. |
Relation | thesis |
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