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Nico J. Smit - One of the best experts on this subject based on the ideXlab platform.

  • molecular insights into the identification and phylogenetics of the cosmopolitan marine fish blood parasite Haemogregarina bigemina adeleorina haemogregarinidae
    International journal for parasitology. Parasites and wildlife, 2019
    Co-Authors: Polly M. Hayes, Nico J. Smit
    Abstract:

    Abstract Haemogregarina bigemina is one of the most prevalent haemogregarines of marine fishes and has long been considered an enigmatic and cosmopolitan species. However, to determine whether H. bigemina truly represents a single global species, or whether it should be partitioned into several species or subspecies, and to confirm its taxonomic status among the Haemogregarina, molecular analysis is required. Here, we provide the first molecular characterisation of H. bigemina from one of its type hosts, Lipophrys pholis, in the UK using 18S rDNA sequences. Phylogenetic and p-distance comparisons of the newly generated H. bigemina sequences with those published from other haemogregarine taxa and related apicomplexans suggest that H. bigemina falls outside of the “Haemogregarina” clade as well as the Adeleorina altogether, forming a separate apicomplexan marine clade, and appears to be in fact more closely related to other non-haemogregarine Apicomplexa genera. Further work including sequences of H. bigemina and H. bigemina-like parasites observed from fishes in other localities is now needed to investigate this further.

  • Molecular insights into the identification and phylogenetics of the cosmopolitan marine fish blood parasite, Haemogregarina bigemina (Adeleorina: Haemogregarinidae)
    'Elsevier BV', 2019
    Co-Authors: Polly M. Hayes, Nico J. Smit
    Abstract:

    Haemogregarina bigemina is one of the most prevalent haemogregarines of marine fishes and has long been considered an enigmatic and cosmopolitan species. However, to determine whether H. bigemina truly represents a single global species, or whether it should be partitioned into several species or subspecies, and to confirm its taxonomic status among the Haemogregarina, molecular analysis is required. Here, we provide the first molecular characterisation of H. bigemina from one of its type hosts, Lipophrys pholis, in the UK using 18S rDNA sequences. Phylogenetic and p-distance comparisons of the newly generated H. bigemina sequences with those published from other haemogregarine taxa and related apicomplexans suggest that H. bigemina falls outside of the “Haemogregarina” clade as well as the Adeleorina altogether, forming a separate apicomplexan marine clade, and appears to be in fact more closely related to other non-haemogregarine Apicomplexa genera. Further work including sequences of H. bigemina and H. bigemina-like parasites observed from fishes in other localities is now needed to investigate this further. Keywords: Haemogregarina bigemina, Blood parasites, Apicomplexa, Lipophrys pholis, 18S rDNA, Phylogenetic tree

  • nov. parasitising three Amietophrynus species
    2016
    Co-Authors: Edward C Netherl, Courtney A. Cook, Nico J. Smit
    Abstract:

    DOI 10.1186/s13071-014-0552-0Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africastages, and molecular findings, supported all three haemogregarine isolates from all three Amietophrynus species to be the same, a species of Hepatozoon, and furthermore different morphologically from other previously recorded bufonid Hepatozoon species. The haemogregarine fell within a clade comprising other anuran Hepatozoon species and furthermore, within a monophyletic sub-clade along with H. theileri and are described as Hepatozoon ixoxo sp. nov. (Continued on next page

  • Redescription, molecular characterisation and taxonomic re-evaluation of a unique African monitor lizard haemogregarine Karyolysus paradoxa (Dias, 1954) n. comb. (Karyolysidae)
    Parasites & vectors, 2016
    Co-Authors: Courtney A. Cook, Edward C. Netherlands, Nico J. Smit
    Abstract:

    Background Within the African monitor lizard family Varanidae, two haemogregarine genera have been reported. These comprise five species of Hepatozoon Miller, 1908 and a species of Haemogregarina Danilewsky, 1885. Even though other haemogregarine genera such as Hemolivia Petit, Landau, Baccam & Lainson, 1990 and Karyolysus Labbe, 1894 have been reported parasitising other lizard families, these have not been found infecting the Varanidae. The genus Karyolysus has to date been formally described and named only from lizards of the family Lacertidae and to the authors’ knowledge, this includes only nine species. Molecular characterisation using fragments of the 18S gene has only recently been completed for but two of these species. To date, three Hepatozoon species are known from southern African varanids, one of these Hepatozoon paradoxa (Dias, 1954) shares morphological characteristics alike to species of the family Karyolysidae. Thus, this study aimed to morphologically redescribe and characterise H. paradoxa molecularly, so as to determine its taxonomic placement.

  • INTRAERYTHROCYTIC MEROGONY IN Haemogregarina KOPPIENSIS
    2015
    Co-Authors: Apicomplexa Adeleorina Haemogregarinidae, Nico J. Smit, Angela J. Davies
    Abstract:

    Abstract. During October 2003, a specimen of Ambly-rhynchotes honckenii (Bloch, 1795) was captured at low tide, with a hand net, in a rock pool at Koppie Alleen, De Hoop Nature Reserve, South Africa. This fish was heavily para-sitized by unidentified gnathiid praniza larvae, caligid cope-pods identified as Caligus tetrodontis Barnard, 1948, cymothoid isopods identified as Cinusa tetrodontis (Schioedte et Meinert, 1884), and the blood protozoan Haemogregarina koppiensis Smit et Davies, 2001. Giemsa-stained blood smears from this fish revealed new and unusual stages of merogony for H. koppiensis that included small, rounded, likely intra-erythrocytic merozoites arranged in circles of eight around the host nucleus. Host cells appeared ghost-like and enlarged compared with normal erythrocytes. Identical merozoites, usually in clusters of up to 16, were also observed free of host cells. The pattern of merogony seen in H. koppiensis is un-usual for a fish haemogregarine. Haemogregarina (sensu lato) koppiensis Smit et Davies, 2001 from the evileye pufferfish Amblyrhynchotes honckenii (Bloch, 1795) was only the second valid species of haemo-gregarine to have been named from marine fish in South Africa (see Smit and Davies 2001), the first being Haemo-gregarina (s.l.) bigemina Laveran et Mesnil, 1901 (see Smi

Angela J. Davies - One of the best experts on this subject based on the ideXlab platform.

  • the Patos Lagoon Estuary, Southern Brazil
    2016
    Co-Authors: Angela J. Davies, Lílian Lund Amado, Richard T. Cook, Adalto Bianchini, Jorge C. Eiras
    Abstract:

    Potential environmental and host gender influences on prevalence of Haemogregarina platessae (Adeleorina: Haemogregarinidae) and suspected Haemohormidium terraenovae (incertae sedis) in Brazilian flounder fro

  • INTRAERYTHROCYTIC MEROGONY IN Haemogregarina KOPPIENSIS
    2015
    Co-Authors: Apicomplexa Adeleorina Haemogregarinidae, Nico J. Smit, Angela J. Davies
    Abstract:

    Abstract. During October 2003, a specimen of Ambly-rhynchotes honckenii (Bloch, 1795) was captured at low tide, with a hand net, in a rock pool at Koppie Alleen, De Hoop Nature Reserve, South Africa. This fish was heavily para-sitized by unidentified gnathiid praniza larvae, caligid cope-pods identified as Caligus tetrodontis Barnard, 1948, cymothoid isopods identified as Cinusa tetrodontis (Schioedte et Meinert, 1884), and the blood protozoan Haemogregarina koppiensis Smit et Davies, 2001. Giemsa-stained blood smears from this fish revealed new and unusual stages of merogony for H. koppiensis that included small, rounded, likely intra-erythrocytic merozoites arranged in circles of eight around the host nucleus. Host cells appeared ghost-like and enlarged compared with normal erythrocytes. Identical merozoites, usually in clusters of up to 16, were also observed free of host cells. The pattern of merogony seen in H. koppiensis is un-usual for a fish haemogregarine. Haemogregarina (sensu lato) koppiensis Smit et Davies, 2001 from the evileye pufferfish Amblyrhynchotes honckenii (Bloch, 1795) was only the second valid species of haemo-gregarine to have been named from marine fish in South Africa (see Smit and Davies 2001), the first being Haemo-gregarina (s.l.) bigemina Laveran et Mesnil, 1901 (see Smi

  • REVIEW ARTICLE Haemogregarina bigemina (Protozoa: Apicomplexa: Adeleorina)
    2015
    Co-Authors: Angela J. Davies, Nico J. Smit, Polly M. Hayes, Alan M Seddon, David Wertheim
    Abstract:

    Abstract. This paper reviews past, current and likely future research on the fish haemogregarine, Haemogregarina bigemina Laveran et Mesnil, 1901. Recorded from 96 species of fishes, across 70 genera and 34 families, this broad distribution for H. bigemina is questioned. In its type hosts and other fishes, the parasite undergoes intraerythrocytic binary fission, finally forming mature paired gamonts. An intraleukocytic phase is also reported, but not from the type hosts. This paper asks whether stages from the white cell series are truly H. bigemina. A future aim should be to compare the molecular constitution of so-called H. bigemina from a number of locations to determine whether all represent the same species. The transmission of H. bigemina between fishes is also considered. Past studies show that young fish acquire the haemogregarine when close to metamorphosis, but vertical and faecal-oral transmission seem unlikely. Some fish haemogregarines are leech-transmitted, but where fish populations with H. bigemina have been studied, these annelids are largely absent. However, haematophagous larval gnathiid isopods occur on such fishes and may be readily eaten by them. Sequential squashes of gnathiids from fishes with H. bigemina have demonstrated development of the haemogregarine in these isopods. Examination of histological sections through gnathiids is now underway to determine the precise development sites of the haemogregarine, particularly whether merozoites finally invade the salivary glands. To assist in this procedure and to clarify the internal anatomy of gnathiids, 3D visualisation of stacked, serial histological sections is being undertaken. Biological transmission experiments should follow these processes. Haemogregarines are apicomplexan protozoa

  • reassignment of the land tortoise haemogregarine Haemogregarina fitzsimonsi dias 1953 adeleorina haemogregarinidae to the genus hepatozoon miller 1908 adeleorina hepatozoidae based on parasite morphology life cycle and phylogenetic analysis of 18s rd
    Parasitology, 2014
    Co-Authors: Courtney A. Cook, Angela J. Davies, Scott P Lawton, Nico J. Smit
    Abstract:

    SUMMARY Research was undertaken to clarify the true taxonomic position of the terrestrial tortoise apicomplexan, Haemogregarina fitzsimonsi (Dias, 1953). Thin blood films were screened from 275 wild and captive South African tortoises of 6 genera and 10 species between 2009-2011. Apicomplexan parasites within films were identified, with a focus on H. fitzsimonsi. Ticks from wild tortoises, especially Amblyomma sylvaticum and Amblyomma marmoreum were also screened, and sporogonic stages were identified on dissection of adult ticks of both species taken from H. fitzsimonsi infected and apparently non-infected tortoises. Parasite DNA was extracted from fixed, Giemsa-stained tortoise blood films and from both fresh and fixed ticks, and PCR was undertaken with two primer sets, HEMO1/HEMO2, and HepF300/HepR900, to amplify parasite 18S rDNA. Results indicated that apicomplexan DNA extracted from tortoise blood films and both species of tick had been amplified by one or both primer sets. Haemogregarina  fitzsimonsi 18S rDNA sequences from tortoise blood aligned with those of species of Hepatozoon, rather than those of species of Haemogregarina or Hemolivia. It is recommended therefore that this haemogregarine be re-assigned to the genus Hepatozoon, making Hepatozoon fitzsimonsi (Dias, 1953) the only Hepatozoon known currently from any terrestrial chelonian. Ticks are its likely vectors.

  • gnathia aureamaculosa a likely definitive host of Haemogregarina balistapi and potential vector for Haemogregarina bigemina between fishes of the great barrier reef australia
    International Journal for Parasitology, 2013
    Co-Authors: Lynda M Curtis, Nico J. Smit, Angela J. Davies, Alexandra S Grutter
    Abstract:

    Investigations to determine whether juvenile gnathiid isopods are vectors of haemogregarines between coral reef fishes were undertaken at Lizard Island, Australia. Haemogregarina balistapi parasitaemias in triggerfish, Rhinecanthus aculeatus, decreased under gnathiid-free, laboratory conditions, compared with those in tagged R. aculeatus returned to the reef. Gnathia aureamaculosa juveniles were common ectoparasites of reef R. aculeatus and laboratory reared specimens of this gnathiid were fed on R. aculeatus infected with H. balistapi. Subsequent squashes of this gnathiid contained haemogregarine gamonts similar to those seen in blood films of R. aculeatus, and haemogregarine developmental stages, including oocysts, sporozoites, meronts and merozoites. Biological transmission of H. balistapi and a second haemogregarine species, Haemogregarina bigemina, using laboratory reared gnathiids to several species of triggerfishes and surgeonfishes raised from larvae was then attempted. Investigations involved recipient fish ingesting, or being bitten by, G. aureamaculosa juveniles fed on donor fish with haemogregarines; control fish were exposed to gnathiids fed on uninfected donor fish. Subsequently, no haemogregarines were detected in recipient triggerfishes and controls were negative. However, a recipient surgeonfish, Acanthurus xanthopterus, which had ingested gnathiids likely infected with donor fish H. balistapi, carried H. bigemina-like stages. A second recipient surgeonfish, which had ingested gnathiids presumed to be infected with H. bigemina, also carried haemogregarine stages. Finally, a third surgeonfish apparently carried haemogregarines after gnathiids presumed to be infected with H. bigemina had bitten this fish, although not all gnathiids were recovered during the trials and the third infected surgeonfish may have also ingested gnathiids. The study provides strong evidence that G. aureamaculosa is the definitive host of H. balistapi, to our knowledge the first such observation from a coral reef environment. Although transmission of H. balistapi has not yet been demonstrated, laboratory trials tend to support the view that G. aureamaculosa is also a potential vector of H. bigemina between surgeonfish.

Courtney A. Cook - One of the best experts on this subject based on the ideXlab platform.

  • nov. parasitising three Amietophrynus species
    2016
    Co-Authors: Edward C Netherl, Courtney A. Cook, Nico J. Smit
    Abstract:

    DOI 10.1186/s13071-014-0552-0Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africastages, and molecular findings, supported all three haemogregarine isolates from all three Amietophrynus species to be the same, a species of Hepatozoon, and furthermore different morphologically from other previously recorded bufonid Hepatozoon species. The haemogregarine fell within a clade comprising other anuran Hepatozoon species and furthermore, within a monophyletic sub-clade along with H. theileri and are described as Hepatozoon ixoxo sp. nov. (Continued on next page

  • Redescription, molecular characterisation and taxonomic re-evaluation of a unique African monitor lizard haemogregarine Karyolysus paradoxa (Dias, 1954) n. comb. (Karyolysidae)
    Parasites & vectors, 2016
    Co-Authors: Courtney A. Cook, Edward C. Netherlands, Nico J. Smit
    Abstract:

    Background Within the African monitor lizard family Varanidae, two haemogregarine genera have been reported. These comprise five species of Hepatozoon Miller, 1908 and a species of Haemogregarina Danilewsky, 1885. Even though other haemogregarine genera such as Hemolivia Petit, Landau, Baccam & Lainson, 1990 and Karyolysus Labbe, 1894 have been reported parasitising other lizard families, these have not been found infecting the Varanidae. The genus Karyolysus has to date been formally described and named only from lizards of the family Lacertidae and to the authors’ knowledge, this includes only nine species. Molecular characterisation using fragments of the 18S gene has only recently been completed for but two of these species. To date, three Hepatozoon species are known from southern African varanids, one of these Hepatozoon paradoxa (Dias, 1954) shares morphological characteristics alike to species of the family Karyolysidae. Thus, this study aimed to morphologically redescribe and characterise H. paradoxa molecularly, so as to determine its taxonomic placement.

  • first hemolivia from southern africa reassigning chelonian Haemogregarina parvula dias 1953 adeleorina haemogregarinidae to hemolivia adeleorina karyolysidae
    African Zoology, 2015
    Co-Authors: Courtney A. Cook, Edward C. Netherlands, Nico J. Smit
    Abstract:

    To date, only a single species of Hemolivia, Hemolivia mauritanica (Sergent & Sergent, 1904), has been described from African terrestrial tortoises. Although various haemogregarines have been described from southern African terrapins and tortoises, including species from the genus Haemogregarina and one from the genus Hepatozoon, no species of Hemolivia have been identified previously from southern Africa. Since its morphological redescription, the taxonomic placement of one of these species, Haemogregarina parvula Dias, 1953, was in doubt. Hence, research was undertaken to resolve the true taxonomic position of this haemogregarine. Blood smears from nine wild tortoises of two species, Stigmochelys pardalis and Kinixys zombensis, from South Africa were screened, with the focus on H. parvula. Parasite DNA was extracted from ethanol-preserved blood samples, and fragments of the 18S rDNA gene were amplified by PCR using the primer sets HepF300/HepR900 and 4558/2733. Maximum likelihood and maximum parsimony a...

  • hepatozoon species adeleorina hepatozoidae of african bufonids with morphological description and molecular diagnosis of hepatozoon ixoxo sp nov parasitising three amietophrynus species anura bufonidae
    Parasites & Vectors, 2014
    Co-Authors: Edward C. Netherlands, Courtney A. Cook, Nico J. Smit
    Abstract:

    Haemogregarines comprise a large group of apicomplexan blood parasites. In 1996 all anuran haemogregarines still in the genus Haemogregarina Danilewsky, 1885 were reassigned to the genus Hepatozoon Miller, 1908. Most (11/15, 73%) African anuran Hepatozoon species have been recorded from the family Bufonidae, however, all these are recorded from only two host species, Amietophrynus mauritanicus (Schlegel, 1841) and Amietophrynus regularis (Reuss, 1833) from Northern and central Africa. To the authors’ knowledge the only description of an anuran haemogregarine from South Africa is Hepatozoon theileri (Laveran, 1905), parasitising Amietia quecketti (Boulenger, 1895). Thin blood smears for morphometrics and whole blood for molecular work, were collected from 32 Amietophrynus garmani (Meek, 1897), 12 Amietophrynus gutturalis (Power, 1927), and nine Amietophrynus maculatus (Hallowell, 1854), in Ndumo Game Reserve and Kwa Nyamazane Conservancy, KwaZulu-Natal, South Africa. Smears were Giemsa-stained, screened for haemogregarines, parasite stages measured, compared to each other and to other described African bufonid haemogregarines. Parasite 18S rDNA was amplified using two apicomplexan-specific primer sets, HepF300/HepR900 and 4558/2733. Resulting sequences of the haemogregarine isolates from the three Amietophrynus species were compared with each other and to comparative haemogregarine sequences selected from GenBank. Morphological characteristics of parasite stages, in particular characteristically capped mature gamont stages, and molecular findings, supported all three haemogregarine isolates from all three Amietophrynus species to be the same, a species of Hepatozoon, and furthermore different morphologically from other previously recorded bufonid Hepatozoon species. The haemogregarine fell within a clade comprising other anuran Hepatozoon species and furthermore, within a monophyletic sub-clade along with H. theileri and are described as Hepatozoon ixoxo sp. nov. This is the first morphological and molecular account of Hepatozoon species within the family Bufonidae from South Africa, a study hoped to encourage the redescription and molecular analysis of those Hepatozoon species described in the past from Amietophrynus species, as well as to promote the use of both morphological and molecular characteristics in Hepatozoon species descriptions. This will aid in comprehensive Hepatozoon descriptions, which along with the use of phylogenetic analysis will give a better indication of these parasites possible vectors and life cycle dynamics.

  • redescription and molecular diagnosis of hepatozoon theileri laveran 1905 apicomplexa adeleorina hepatozoidae infecting amietia quecketti anura pyxicephalidae
    Folia Parasitologica, 2014
    Co-Authors: Edward C. Netherlands, Courtney A. Cook, Nico J. Smit, Louis H Du Preez
    Abstract:

    Blood smears prepared from the peripheral blood of 20 wild caught Amietia quecketti (Boulenger) from the North-West University Botanical Gardens, North West Province, South Africa, were examined for the presence of haemogregarines. A haemogregarine species comparative in morphology, host and geographical locality to that of Haemogregarina theileri Laveran, 1905 was detected. The original description of H. theileri was based solely on frog peripheral blood gamont stages. Later, further parasite stages, including trophozoites and merogonic liver stages, were recorded in a related Amietia sp. from equatorial Africa. This species was originally classified as a member of the genus Haemogregarina Danilewsky, 1885, but due to the close life cycle and morphological resemblance to those of Hepatozoon species, H. theileri was later transferred from Haemogregarina to Hepatozoon Miller, 1908. In the present study, meront and merozoite stages not described before, along with previously observed trophozoite, immature and mature gamont stages, are described from the peripheral blood of hosts. In addition, comparative phylogenetic analysis of the partial 18S rDNA sequence of Hepatozoon theileri to those of other haemogregarine species, including those of species of Hepatozoon and a Haemogregarina, support the taxonomic transfer of H. theileri to Hepatozoon, nesting H. theileri within a clade comprising species parasitising other amphibians. This is the first molecular and phylogenetic analysis of an African anuran species of Hepatozoon.

Edward C. Netherlands - One of the best experts on this subject based on the ideXlab platform.

  • Redescription, molecular characterisation and taxonomic re-evaluation of a unique African monitor lizard haemogregarine Karyolysus paradoxa (Dias, 1954) n. comb. (Karyolysidae)
    Parasites & vectors, 2016
    Co-Authors: Courtney A. Cook, Edward C. Netherlands, Nico J. Smit
    Abstract:

    Background Within the African monitor lizard family Varanidae, two haemogregarine genera have been reported. These comprise five species of Hepatozoon Miller, 1908 and a species of Haemogregarina Danilewsky, 1885. Even though other haemogregarine genera such as Hemolivia Petit, Landau, Baccam & Lainson, 1990 and Karyolysus Labbe, 1894 have been reported parasitising other lizard families, these have not been found infecting the Varanidae. The genus Karyolysus has to date been formally described and named only from lizards of the family Lacertidae and to the authors’ knowledge, this includes only nine species. Molecular characterisation using fragments of the 18S gene has only recently been completed for but two of these species. To date, three Hepatozoon species are known from southern African varanids, one of these Hepatozoon paradoxa (Dias, 1954) shares morphological characteristics alike to species of the family Karyolysidae. Thus, this study aimed to morphologically redescribe and characterise H. paradoxa molecularly, so as to determine its taxonomic placement.

  • first hemolivia from southern africa reassigning chelonian Haemogregarina parvula dias 1953 adeleorina haemogregarinidae to hemolivia adeleorina karyolysidae
    African Zoology, 2015
    Co-Authors: Courtney A. Cook, Edward C. Netherlands, Nico J. Smit
    Abstract:

    To date, only a single species of Hemolivia, Hemolivia mauritanica (Sergent & Sergent, 1904), has been described from African terrestrial tortoises. Although various haemogregarines have been described from southern African terrapins and tortoises, including species from the genus Haemogregarina and one from the genus Hepatozoon, no species of Hemolivia have been identified previously from southern Africa. Since its morphological redescription, the taxonomic placement of one of these species, Haemogregarina parvula Dias, 1953, was in doubt. Hence, research was undertaken to resolve the true taxonomic position of this haemogregarine. Blood smears from nine wild tortoises of two species, Stigmochelys pardalis and Kinixys zombensis, from South Africa were screened, with the focus on H. parvula. Parasite DNA was extracted from ethanol-preserved blood samples, and fragments of the 18S rDNA gene were amplified by PCR using the primer sets HepF300/HepR900 and 4558/2733. Maximum likelihood and maximum parsimony a...

  • hepatozoon species adeleorina hepatozoidae of african bufonids with morphological description and molecular diagnosis of hepatozoon ixoxo sp nov parasitising three amietophrynus species anura bufonidae
    Parasites & Vectors, 2014
    Co-Authors: Edward C. Netherlands, Courtney A. Cook, Nico J. Smit
    Abstract:

    Haemogregarines comprise a large group of apicomplexan blood parasites. In 1996 all anuran haemogregarines still in the genus Haemogregarina Danilewsky, 1885 were reassigned to the genus Hepatozoon Miller, 1908. Most (11/15, 73%) African anuran Hepatozoon species have been recorded from the family Bufonidae, however, all these are recorded from only two host species, Amietophrynus mauritanicus (Schlegel, 1841) and Amietophrynus regularis (Reuss, 1833) from Northern and central Africa. To the authors’ knowledge the only description of an anuran haemogregarine from South Africa is Hepatozoon theileri (Laveran, 1905), parasitising Amietia quecketti (Boulenger, 1895). Thin blood smears for morphometrics and whole blood for molecular work, were collected from 32 Amietophrynus garmani (Meek, 1897), 12 Amietophrynus gutturalis (Power, 1927), and nine Amietophrynus maculatus (Hallowell, 1854), in Ndumo Game Reserve and Kwa Nyamazane Conservancy, KwaZulu-Natal, South Africa. Smears were Giemsa-stained, screened for haemogregarines, parasite stages measured, compared to each other and to other described African bufonid haemogregarines. Parasite 18S rDNA was amplified using two apicomplexan-specific primer sets, HepF300/HepR900 and 4558/2733. Resulting sequences of the haemogregarine isolates from the three Amietophrynus species were compared with each other and to comparative haemogregarine sequences selected from GenBank. Morphological characteristics of parasite stages, in particular characteristically capped mature gamont stages, and molecular findings, supported all three haemogregarine isolates from all three Amietophrynus species to be the same, a species of Hepatozoon, and furthermore different morphologically from other previously recorded bufonid Hepatozoon species. The haemogregarine fell within a clade comprising other anuran Hepatozoon species and furthermore, within a monophyletic sub-clade along with H. theileri and are described as Hepatozoon ixoxo sp. nov. This is the first morphological and molecular account of Hepatozoon species within the family Bufonidae from South Africa, a study hoped to encourage the redescription and molecular analysis of those Hepatozoon species described in the past from Amietophrynus species, as well as to promote the use of both morphological and molecular characteristics in Hepatozoon species descriptions. This will aid in comprehensive Hepatozoon descriptions, which along with the use of phylogenetic analysis will give a better indication of these parasites possible vectors and life cycle dynamics.

  • redescription and molecular diagnosis of hepatozoon theileri laveran 1905 apicomplexa adeleorina hepatozoidae infecting amietia quecketti anura pyxicephalidae
    Folia Parasitologica, 2014
    Co-Authors: Edward C. Netherlands, Courtney A. Cook, Nico J. Smit, Louis H Du Preez
    Abstract:

    Blood smears prepared from the peripheral blood of 20 wild caught Amietia quecketti (Boulenger) from the North-West University Botanical Gardens, North West Province, South Africa, were examined for the presence of haemogregarines. A haemogregarine species comparative in morphology, host and geographical locality to that of Haemogregarina theileri Laveran, 1905 was detected. The original description of H. theileri was based solely on frog peripheral blood gamont stages. Later, further parasite stages, including trophozoites and merogonic liver stages, were recorded in a related Amietia sp. from equatorial Africa. This species was originally classified as a member of the genus Haemogregarina Danilewsky, 1885, but due to the close life cycle and morphological resemblance to those of Hepatozoon species, H. theileri was later transferred from Haemogregarina to Hepatozoon Miller, 1908. In the present study, meront and merozoite stages not described before, along with previously observed trophozoite, immature and mature gamont stages, are described from the peripheral blood of hosts. In addition, comparative phylogenetic analysis of the partial 18S rDNA sequence of Hepatozoon theileri to those of other haemogregarine species, including those of species of Hepatozoon and a Haemogregarina, support the taxonomic transfer of H. theileri to Hepatozoon, nesting H. theileri within a clade comprising species parasitising other amphibians. This is the first molecular and phylogenetic analysis of an African anuran species of Hepatozoon.

Smit, Nico J. - One of the best experts on this subject based on the ideXlab platform.

  • First record of an intraleucocytic haemogregarine (Adeleorina: Haemogregarinidae) from South African tortoises of the species Stigmochelys pardalis (Cryptodira: Testudinidae)
    NISC (Pty) Ltd, 2017
    Co-Authors: Cook, Courtney A, Smit, Nico J., Davies, Angela J.
    Abstract:

    To date, four intraerythrocytic apicomplexans, namely the haemogregarines Haemogregarina fitzsimonsi and Haemogregarina parvula, and the haemoproteids Haemoproteus testudinalis and Haemoproteus natalensis, have been described from South African land tortoises. Recently, an intraleucocytic haemogregarine was observed in one species of tortoise, Stigmochelys pardalis, from the province of KwaZulu-Natal. Gamonts were identified in the monocytes and lymphocytes of 5/126 (4%) S. pardalis, but no additional stages were detected. Mixed infections with H. fitzsimonsi were observed for 2/5 (40%) of the parasitized S. pardalis, but the intraleucocytic gamont stages were larger than the intraerythrocytic gamont stages of both H. fitzsimonsi and H. parvula. The only other record of a chelonian intraleucocytic haemogregarine is of Haemogregarina pseudemydis, with stages described from the red and white blood cells of neotropical terrapins. Thus, the report of an intraleucocytic haemogregarine infecting a terrestrial tortoise from Africa is significant, although its taxonomic placement remains problematic at present.Key words: intraleucocytic, haemogregarine, tortoise blood parasite, SouthAfrican, apicomplexan taxonomy

  • Life cycle of Hepatozoon affluomaloti sp. n. (Apicomplexa: Haemogregarinidae) in crag lizards (Sauria: Cordylidae) and in culicine mosquitoes from South Africa.
    'Biology Centre AS CR', 2015
    Co-Authors: Van As Johann, Davies Angela, Smit, Nico J.
    Abstract:

    A new haemogregarine species Hepatozoon affluomaloti sp. n. is described from erythrocytes in the peripheral blood of crag lizards Pseudocordylus melanotus (Smith) and Pseudocordylus subviridis (Smith) (Sauria: Cordylidae) from mountainous regions in the Eastern Free State, South Africa. This species can be distinguished from all other congeners based on its large size, staining properties and life cycle development in its vector, Culex (Afroculex) lineata (Theobald) (Diptera: Culicidae). Mature gamonts stain mostly uniformly pinkish-purple with Giemsa, sometimes containing darker azurophilic granules anterior and posterior to the nucleus. The reflexed posterior extremity of the gamont stage sometimes stains slightly deeper purple and the nucleus is dense and placed in the posterior third of the parasite body. Merogonic stages of this haemogregarine occur in the liver tissues of P. melanotus with dizoic meronts. Macromeronts contains 2-7 macromerozoites and micromeronts contains 9-24 micromerozoites. Sporogonic developmental stages found in the proposed final host and vector, C. lineata, include large oocysts, measuring 54 × 48 µm on average. Sporulating oocysts with 8 nuclei are present in mosquitoes 6-7 days post-feeding on infected lizards. Sporocysts with mature sporozoites measure 31.0 × 21.8 µm on average and each contains 2-8 large sporozoites. It is suggested that transmission of infective sporozoites is achieved through predation of lizards on mosquitoes

  • First Hemolivia from southern Africa: reassigning chelonian Haemogregarina parvula Dias, 1953 (Adeleorina: Haemogregarinidae) to Hemolivia (Adeleorina: Karyolysidae)
    SCOTTSVILLE, 2015
    Co-Authors: Cook, Courtney A, Netherlands, Edward Charles, Smit, Nico J.
    Abstract:

    To date, only a single species of Hemolivia, Hemolivia mauritanica (Sergent & Sergent, 1904), has been described from African terrestrial tortoises. Although various haemogregarines have been described from southern African terrapins and tortoises, including species from the genus Haemogregarina and one from the genus Hepatozoon, no species of Hemolivia have been identified previously from southern Africa. Since its morphological redescription, the taxonomic placement of one of these species, Haemogregarina parvula Dias, 1953, was in doubt. Hence, research was undertaken to resolve the true taxonomic position of this haemogregarine. Blood smears from nine wild tortoises of two species, Stigmochelys pardalis and Kinixys zombensis, from South Africa were screened, with the focus on H. parvula. Parasite DNA was extracted from ethanol-preserved blood samples, and fragments of the 18S rDNA gene were amplified by PCR using the primer sets HepF300/HepR900 and 4558/2733. Maximum likelihood and maximum parsimony analyses of 18S rDNA sequences showed that Haemogregarina parvula formed a monophyletic clade with species of Hemolivia within the Hepatozoon clade, not with species of Haemogregarina. It is thus recommended that this haemogregarine be reassigned to the genus Hemolivia, rendering Hemolivia parvula (Dias, 1953) the first species of the genus recorded from southern African tortoises.status: publishe

  • First Hemolivia from southern Africa: reassigning chelonian Haemogregarina parvula Dias, 1953 (Adeleorina: Haemogregarinidae) to Hemolivia (Adeleorina: Karyolysidae)
    'Informa UK Limited', 2015
    Co-Authors: Cook, Courtney A, Netherlands, Edward C., Smit, Nico J.
    Abstract:

    To date, only a single species of Hemolivia, Hemolivia mauritanica (Sergent & Sergent, 1904), has been described from African terrestrial tortoises. Although various haemogregarines have been described from southern African terrapins and tortoises, including species from the genus Haemogregarina and one from the genus Hepatozoon, no species of Hemolivia have been identified previously from southern Africa. Since its morphological redescription, the taxonomic placement of one of these species, Haemogregarina parvula Dias, 1953, was in doubt. Hence, research was undertaken to resolve the true taxonomic position of this haemogregarine. Blood smears from nine wild tortoises of two species, Stigmochelys pardalis and Kinixys zombensis, from South Africa were screened, with the focus on H. parvula. Parasite DNA was extracted from ethanol-preserved blood samples, and fragments of the 18S rDNA gene were amplified by PCR using the primer sets HepF300/HepR900 and 4558/2733. Maximum likelihood and maximum parsimony analyses of 18S rDNA sequences showed that Haemogregarina parvula formed a monophyletic clade with species of Hemolivia within the Hepatozoon clade, not with species of Haemogregarina. It is thus recommended that this haemogregarine be reassigned to the genus Hemolivia, rendering Hemolivia parvula (Dias, 1953) the first species of the genus recorded from southern African tortoise

  • Hepatozoon species (Adeleorina: Hepatozoidae) of African bufonids, with morphological description and molecular diagnosis of Hepatozoon ixoxo sp. nov. parasitising three Amietophrynus species (Anura: Bufonidae)
    BioMed Central Ltd., 2014
    Co-Authors: Netherlands, Edward Charles, Cook, Courtney A, Smit, Nico J.
    Abstract:

    Haemogregarines comprise a large group of apicomplexan blood parasites. In 1996 all anuran haemogregarines still in the genus Haemogregarina Danilewsky, 1885 were reassigned to the genus Hepatozoon Miller, 1908. Most (11/15, 73%) African anuran Hepatozoon species have been recorded from the family Bufonidae, however, all these are recorded from only two host species, Amietophrynus mauritanicus (Schlegel, 1841) and Amietophrynus regularis (Reuss, 1833) from Northern and central Africa. To the authors' knowledge the only description of an anuran haemogregarine from South Africa is Hepatozoon theileri (Laveran, 1905), parasitising Amietia quecketti (Boulenger, 1895).status: publishe