Monogeneans on native and introduced freshwater fishes from Cuba with the description of a new species of Salsuginus Beverley-Burton, 1984 from Limia vittata (Poeciliidae)

During a parasitological survey carried out between March and September 2003 in Cuba, the following monogeneans were found on the gills of freshwater fishes: Salsuginus cubensis n. sp. on the Cuban molly Limia vittata Guichenot (Poeciliidae); Cichlidogyrus sclerosus Paperna & Thurston, 1969 and C. tilapiae Paperna, 1960 on the African cichlid Tilapia rendalli Boulenger (Cichlidae); Haplocleidus dispar Mueller, 1936 and Pterocleidus acer Mueller, 1936 (all Dactylogyridae) on the sunfish Lepomis macrochirus Rafinesque (Centrarchidae) (new geographical records); and Gyrodactylus sp. (Gyrodactylidae) on the biajaca Nandopsis tetracanthus Valenciennes (Cichlidae) (new host and geographical record). Salsuginus cubensis differs from all other species of the genus in the size and morphology of the copulatory complex. The occurrence of C. sclerosus, C. tilapiae, H. dispar and P. acer in their respective hosts is due to the introduction of these hosts to Cuba. A review of the species composition of the Monogenea in native and introduced freshwater fish from Cuba is presented and the zoogeographical distribution of the species found is briefly discussed.     

The feeding habits of Sargochromis Codringtonii in Lake Kariba, Zimbabwe

The food of adult Sargochromis codringtonii in Lake Kariba was dominated by prosobranch snails with pulmonate snails forming an insignificant dietary component. S. codringtonii does not show particular preference for any snail species, feeding on those species that are readily available. Morphometrical analysis of the feeding structures of S. codringtonii showed that the fish is well adapted to handling a molluscivorous diet. The pharyngeal jaws with their flat crowned teeth are well adapted to crushing molluscs. The daily food consumption rate of S. codringtonii was estimated over different seasons. Estimates of food consumption indicate that the fish consumed 13.96% of their dry body weight per day in summer falling to 4.46% in winter. The low consumption of pulmonate snails suggests that S. codringtonii can not be a successful biological control agent against the vectors of schistosomiasis.     

Redescription of <Emphasis Type="Italic">Cichlidogyrus tiberianus</Emphasis> Paperna, 1960 and <Emphasis Type="Italic">C. dossoui</Emphasis> Douëllou, 1993 (Monogenea: Ancyrocephalidae), with special reference to the male copulatory organ

The flatworms of the genus Cichlidogyrus Paperna, 1960 (Monogenea: Ancyrocephalidae) are gill parasites of freshwater fish, affecting predominantly the family Cichlidae. Cichlidogyrus tiberianus Paperna, 1960 and Cichlidogyrus dossoui Douëllou, 1993 are among the most widely distributed species of the genus, occurring in several African river basins and infecting many different host species, including the economically important Nile tilapia Oreochromis niloticus (Linnaeus) and redbreast tilapia Coptodon rendalli (Boulenger). Despite their wide distribution, C. tiberianus and C. dossoui have so far been studied only by light microscopy. In this paper they are redescribed on the basis of scanning electron microscopy of newly-collected material. The new material was obtained from redbreast tilapia caught in the Luapula River (D. R. Congo). The haptoral sclerites and genitalia are redescribed and illustrated in detail. Special attention is given to the complex morphology of the male copulatory organ.     

Two new species of Cichlidogyrus Paperna, 1960 (Monogenea, ancyrocephalidae) gill parasites on Hemichromis fasciatus (Pisces, Cichlidae) in Africa, with remarks on parasite geographical distribution

The examination of gill parasites from Hemichromis fasciatus Peters, 1858 (Pisces, Cichlidae) in Africa revealed the presence of nine species of Monogenea, three belong to Onchobdella Paperna, 1968 and the others to Cichlidogyrus Paperna, 1960. Seven have been previously described (O. aframae Paperna, 1968; O. bopeleti Bilong Bilong & Euzet, 1995; O. voltensis Paperna, 1968; C. dageti Dossou & Birgi, 1984; C. euzeti Dossou & Birgi, 1984; C. falcifer Dossou & Birgi, 1984 and C. longicirrus Paperna, 1965); two, belonging to the latter genus, are considered as new species: C. sanseoi n. sp. and C. teugelsi n. sp. As parasitic species are not present in all the host distribution area, we think that H. fasciatus is made up of two distinct populations (or even sister species).     

Crustacean parasites of fishes in Lake Kariba,Zimbabwe, preliminary results

During a survey of fish ectoparasites in Lake Kariba (Zimbabwe), two crustaceans were often encountered. Dolops ranarum (Branchiura), parasite of the body, mouth and gill chamber, infected mostly cichlids, the catfish Clarias gariepinus, Synodontis zambezensis and two Mormyrids. Among cichlids clear host preferences were shown. No seasonal variations could be detected in the infections. D. ranarum parasitized predominantly fish above 15 cm in standard length. Lamproglena monodi (Copepoda) parasitized only the gills of cichlids with a preference for Serranochromis codringtonii, S. macrocephalus and Tilapia rendalli. Small fish were seldom infected. Seasonal variations of the prevalence occurred, the hot season being the less favourable. Few other crustaceans were found during the survey: a single specimen of Lamproglena hemprichii on the gills of the tigerfish, Hydrocynus vittatus; three specimens of Afrolernaea longicollis, one found on the gills of Hippopotamyrus discorhynchus and two on the gills of Mormyrops deliciosus; a hundred of Ergasilus mirabilis in a specimen of H. discorhynchus.     

Gill parasites of the genus Cichlidogyrus Paperna, 1960 (Monogenea,Ancyrocephalidae) from Tilapia guineensis (Bleeker, 1862), with descriptions of six new species

A study of gill parasites of Tilapia guineensis (Bleeker, 1862) (Cichlidae) from different locations in West Africa (Senegal, Guinea, the Ivory Coast and the Congo) revealed the presence of twelve species of Cichlidogyrus Paperna, 1960 (Monogenea). Six have been recorded previously from T. zillii (Gervais, 1848) or Tristamella simonis (Günther, 1864) and six are considered new species: C. agnesi n. sp., C. bilongi n. sp., C. gallus n. sp., C. flexicolpos n. sp., C. louipaysani n. sp. and C. vexus n. sp. In the first three species cited, we report the presence of an auxiliary plate in the male copulatory complex which is characteristic of the species C. aegypticus Ergens, 1981, a parasite of Tilapia zillii.     

A review of fur-mites of the genus <Emphasis Type="Italic">Dubininetta</Emphasis> Fain &amp; Lukoschus, 1978 (Acariformes: Listrophoridae), ectoparasites of moles (Soricomorpha: Talpidae)

The fur mite genus Dubininetta Fain & Lukoschus, 1978 (Acariformes: Listrophoridae) represented by ectoparasites of moles (Soricomorpha: Talpidae) is revised. An amended diagnosis of this genus is provided. Two new species are described from moles in Vietnam: Dubininetta euroscaptor n. sp. from Euroscaptor parvidens (Miller) and Dubininetta abramovi n. sp. from Euroscaptor subanura Kawada, Son & Can. The insufficiently described D. taiwanensis (Fain & Lukoschus, 1978) from Mogera insularis (Swinhoe) (type-host) is redescribed based on the type-specimens and numerous newly collected in the Russian Far East specimens from Mogera robusta Nehring. The host ranges are considered for all species of Dubininetta. A key to the five species presently known in this genus is provided.     

Evolutionary relationships,host range and geographical distribution of Camallanus Railliet & Henry, 1915 species (Nematoda: Camallaninae) from clawed toads of the genus Xenopus (Anura: Pipidae)

Representatives of the genus Camallanus Railliet & Henry, 1915 occur mainly in teleost fishes, although a significant number of species have also been recorded from anuran amphibians. The taxonomy, host range, geographical distribution and phylogenetic relationships of Camallanus spp. from African clawed toads (Xenopus spp.) are reviewed. Besides C. kaapstaadi Southwell & Kirshner, 1937, which shows a widespread distribution in sub-Saharan Africa and occurs in X. laevis subspecies, X. wittei, X. fraseri-like toads, X. borealis and X. muelleri, three new species were found: C. siluranae n. sp. from X. tropicalis in west Africa, C. macrocephalus n. sp. from X. borealis in Kenya, and C. xenopodis n. sp. from X. laevis laevis in South Africa and X. borealis in Kenya. C. johni Yeh, 1960 described from Xenopus sp. in Tanzania is considered a species inquirenda. C. kaapstaadi and C. macrocephalus are very closely related and both occur in the oesophagus of their hosts, unlike other Camallanus spp. which are found in the intestine or more rarely the stomach. Some of the unusual morphological features of these species may be an adaptation to attachment in the oesophagus. The host of C. siluranae, X. tropicalis, belongs to a separate species group (as has been established by recent molecular and cytological studies) to those of C. kaapstaadi, C. macrocephalus and C. xenopodis. Morphological affinities suggest that Camallanus spp. from clawed toads are not monophyletic with those from other amphibians and that C. siluranae is distantly related to, and probably not monophyletic with the remaining species from clawed toads. The Camallanus fauna of Xenopus spp. may thus be derived from at least two independent colonisations, of different host clades, by parasite lineages occurring in teleost fishes.     

Cichlidogyrus Paperna, 1960 (Monogenea, Ancyrocephalidae): gill parasites from West African Cichlidae of the subgenus Coptodon Regan, 1920 (Pisces), with descriptions of six new species

A study of gill parasites from fishes of the subgenus Coptodon Regan, 1920 (Cichlidae), namely Tilapia coffea Thys van den Audenaerde, T. dageti Thys van den Audenaerde, T. guineensis (Bleeker), T. louka Thys van den Audenaerde, T. walteri Thys van den Audenaerde and T. zillii (Gervais), from different locations in West Africa (Burkina Fasso, Congo, Ivory Coast, Guinea, Mali and Senegal), revealed the presence of 19 species of Cichlidogyrus Paperna, 1960 (Monogenea, Ancyrocephalidae). Six are considered new species: C. amphoratus n. sp., C. levequei n. sp., C. microscutus n. sp., C. ornatus n. sp., C. ouedraogoi n. sp. and C. yanni n. sp. The host-specificity of these parasites is discussed.     

A complex of the blood fluke genus Psettarium (Digenea: Aporocotylidae) infecting tetraodontiform fishes of east Queensland waters

Seven species of Psettarium (Digenea: Aporocotylidae), including four new species, are reported from tetraodontiform fishes from off coastal east Queensland. Psettarium pandora n. sp. infects the yellow boxfish, Ostracion cubicus (Ostraciidae), the first known aporocotylid to infect this family of fishes. Three new species are reported from pufferfishes of the genus Arothron (Tetraodontidae): Psettarium yoshidai n. sp. infects the map puffer (Arothron mappa), Psettarium hustoni n. sp. infects the black-spotted puffer (A. nigropunctatus) and Psettarium martini n. sp. infects the starry puffer (A. stellatus). We also report three species of Psettarium from Australian waters for the first time. Paracardicola hawaiensis Martin, 1960, the sole species of Paracardicola, is redescribed based on specimens collected from the type-host, the stars-and-stripes puffer, Arothron hispidus. Paracardicola is synonymised with Psettarium and P. hawaiensis is recombined as Psettarium hawaiiense (Martin, 1960) n. comb. Psettarium pulchellum Yong, Cutmore, Bray, Miller, Semarariana, Palm & Cribb, 2016, described from the narrow-lined puffer (Arothron manilensis) from off Bali, Indonesia, is reported from the same fish species at two locations on the Queensland coast, significantly extending the range of this species. Psettarium nolani (Bray, Cribb & Littlewood, 2013), originally described from French Polynesia, is reported from A. hispidus, A. manilensis and A. stellatus, representing both new host and locality records for this species. Molecular phylogenetic analysis shows these species to all be closely related, such that they cannot be considered to represent separate genera despite their differing morphology. Analysis of 28S sequence data for Psettarium anthicum Bullard & Overstreet, 2006, a non-tetraodontiform-infecting species, shows it to be distantly related to all other species of Psettarium for which sequence data are available. The species is re-assigned to a new genus, Cardallagium n. gen., as Cardallagium anthicum (Bullard & Overstreet, 2006) n. comb. We think it likely that the host range of species of Psettarium is limited to tetraodontiform fishes. We assessed the infection biology of two species, P. nolani and P. hawaiiense n. comb. infecting A. hispidus, using histology to assess the pathways of egg release for these species. Eggs of both species were observed in both circulatory and visceral organs of infected hosts, often in high numbers. Eggs were seen trapped in the mucosal layer of the intestine and, in rare instances, causing lesions in the laminar epithelium, providing the strongest evidence yet that they pass through the gut wall and escape the host via the faeces. Lastly, we discuss the biogeographical implications of our findings, noting that some Psettarium species now show very wide geographical distributions.     

New,known and unidentified species of Eulimdana (Nematoda): additional information on biologically unusual filarioids of charadriiform birds

Eulimdana spp. were found in 13 of 32 species of charadriiform birds from North America and Iceland; 88 of 636 adult birds and seven of 72 juvenile birds harboured infections. Described are: E. andersoni n. sp. from Chlidonias niger; E. metcalforum n. sp. from Sterna hirundo; E. sonini n. sp. from Charadrius hiaticula; E. wongae n. sp. from Limosa fedoa; and E. bainae n. sp. from Numenius phaeopus. Eulimdana asperum Bartlett, Anderson, & Bush, 1989 is reported for the second time in its type-host, Phalaropus tricolor. The emerging pattern of one parasite species to one host species suggests that most Eulimdana species are strongly host specific. However, E. florencae Bartlett & Anderson, 1990 is reported for the first time in a second species of Calidris (C. alba) and may be the unidentified species found in C. bairdii, C. alpina and C. pusilla. Other unidentified species were found in Larus pipixcan, Arenaria interpres and Recurvirostra americana. A key to species-groups (three are proposed) and species of Eulimdana in charadriiforms is given. Two pieces of evidence support an earlier suggestion that infections are acquired by neo-natal charadriiforms: (1) the presence of E. wongae in a bird captured as a chick and examined after two months in captivity; and (2) a greater frequency of mixed sex infections with microfilariae in infected juvenile birds (four of seven) than in infected adult birds (five of 88). The latter also supports an earlier suggestion that post-reproductive worms are ephemeral.     

Glyphidohaptor safiensis n. sp. (Monogenea: Ancyrocephalidae) from the white-spotted rabbitfish Siganus canaliculatus (Park) (Perciformes: Siganidae) off Oman,with notes on its phylogenetic position within the Ancyrocephalidae Bychowsky & Nagibina, 1968 (sensu lato)

A new ancyrocephalid monogenean is described from the gills of wild White-spottedrabbitfish Siganus canaliculatus (Park) based on morphological and molecular analyses. Glyphidohaptor safiensis n. sp. can be distinguished from other members of the genus by the shape of the accessory piece of the male copulatory organ (MCO). Unlike its congeners, the rod-shaped accessory piece of G. safiensis n. sp. is distally broad and flattened. The MCO of G. safiensis n. sp. is curved, enclosed in a heavy sheath with a terminal flap. Partial large subunit (LSU), partial small subunit (SSU) and the partial SSU, entire internal transcribed spacer region 1 (ITS1) and partial 5.8S rDNA of the new species and two species of Tetrancistrum Goto & Kikuchi, 1917 from the same host and locality were sequenced and subjected to phylogenetic analysis. The LSU rDNA analysis grouped G. safiensis n. sp. with Tetrancistrum sp. from the gills of Siganus fuscescens Houttuyn from Australia, indicating a possible misidentification of the latter. Sequences of the SSU rDNA of the new species were most similar to those for Pseudohaliotrema sphincteroporus Yamaguti, 1953, demonstrating the close relatedness of the genera Pseudohaliotrema Yamaguti, 1953 and Glyphidohaptor Kritsky, Galli & Yang, 2007 within the Ancyrocephalidae. The comparison of the partial SSU (424 bp) and entire ITS1 and partial 5.8S rDNA (246 bp) sequences obtained for G. safiensis n. sp. with the only available sequence of another member of Glyphidohaptor Kritsky, Galli & Yang, 2007, G. pletocirra Paperna, 1972 (HE601931-HE601933) yielded on average 1.08% dissimilarity (a difference of 7 bases), with a p-distance of 0.010 ± 0.004%. This is the first record of a species of Glyphidohaptor from S. canaliculatus and from the Persian Gulf, the Gulf of Oman and the Arabian Sea.

     

A new species,new host records and life cycle data for lepocreadiids (Digenea) of pomacentrid fishes from the Great Barrier Reef,Australia

A new species of lepocreadiid, Opechonoides opisthoporus n. sp., is described infecting 12 pomacentrid fish species from the Great Barrier Reef, Australia, with Abudefduf whitleyi Allen & Robertson as the type-host. This taxon differs from the only other known member of the genus, Opechonoides gure Yamaguti, 1940, in the sucker width ratio, cirrus-sac length, position of the testes, position of the pore of Laurer’s canal, and relative post-testicular distance. The new species exhibits stenoxenic host-specificity, infecting pomacentrids from seven genera: Abudefduf Forsskål, Amphiprion Bloch & Schneider, Neoglyphidodon Allen, Neopomacentrus Allen, Plectroglyphidodon Fowler & Ball, Pomacentrus Lacépède and Stegastes Jenyns. Phylogenetic analyses of 28S rDNA sequence data demonstrate that O. opisthoporus n. sp. forms a strongly supported clade with Prodistomum orientale (Layman, 1930) Bray & Gibson, 1990. The life cycle of this new species is partly elucidated on the basis of ITS2 rDNA sequence data; intermediate hosts are shown to be three species of Ctenophora. New host records and molecular data are reported for Lepocreadium oyabitcha Machida, 1984 and Lepotrema amblyglyphidodonis Bray, Cutmore & Cribb, 2018, and new molecular data are provided for Lepotrema acanthochromidis Bray, Cutmore & Cribb, 2018 and Lepotrema adlardi (Bray, Cribb & Barker, 1993) Bray & Cribb, 1996. Novel cox1 mtDNA sequence data showed intraspecific geographical structuring between Heron Island and Lizard Island for L. acanthochromidis but not for L. adlardi or O. opisthoporus n. sp.

     

Molecular phylogeny and speciation patterns in host-specific monogeneans (Cichlidogyrus,Dactylogyridae) parasitizing cichlid fishes (Cichliformes,Cichlidae) in Lake Tanganyika

Cichlidogyrus (including Scutogyrus) is the most speciose dactylogyridean monogenean genus known from African and Levantine cichlid fishes (Cichlidae). While its taxonomy is well established, little is known about the phylogenetic relationships and evolutionary history of this ectoparasite, especially from hosts belonging to one of the most impressive vertebrate radiations, the cichlid fishes from the East African Great Lakes and surrounding hydrological systems. Phylogenetic inference based on DNA sequences of the nuclear 18S, internal transcribed spacer 1 and 28S rDNA genes revealed that Cichlidogyrus parasitizing mainly West African cichlid tribes is paraphyletic with respect to species parasitizing hosts belonging to the East African cichlid radiation, which constitute a well-supported monophylum. Members of Cichlidogyrus from tylochromine and oreochromine hosts that colonised Lake Tanganyika only recently, cluster with their non-Lake Tanganyika relatives, indicating that they colonised Lake Tanganyika with their current host species, and did not jump over from any of the many cichlid species already present in the lake. The diversification of Cichlidogyrus in Lake Tanganyika seems to be driven by failure to diverge in old lineages of cichlids, cospeciation in more recently evolved ones, and host switching followed by parasite duplication at the level of the various host tribes. Evaluation of host specificity and structural evolution of haptoral and reproductive organs in Lake Tanganyika Cichlidogyrus revealed that strict specialist species together with larval hook size represent the ancestral state of haptor configuration, suggesting that members of Cichlidogyrus in this system evolved from a very simple form to a more complex one similarly to their West African congeners. Generalist species among Cichlidogyrus with a sclerotized vagina parasitizing ancient Lake Tanganyika lineages seem to have developed a different hook configuration, most probably to ensure successful colonisation of new, phylogenetically unrelated hosts.     

Paradiscogaster flindersi and P. oxleyi n. sp. (Digenea: Faustulidae): overlapping host and geographical distributions in corallivore chaetodontid fishes in the tropical Indo-west Pacific

A total of 2,868 individuals of 47 species of chaetodontids were examined for faustulids at seven major localities in the Tropical Indo-West Pacific (TIWP). Combined morphological and molecular analyses allowed us to describe Paradiscogaster oxleyi n. sp. from three localities in the TIWP and in three host species, Chaetodon lunulatus Quoy & Gaimard (type-host), C. ornatissimus Cuvier and C. meyeri Bloch & Schneider. Molecular analysis of the ITS2 region of rDNA from two host species and three localities supports the morphology-based conclusion that P. oxleyi n. sp. is the same species at the three localities. Paradiscogaster flindersi Bray, Cribb & Barker, 1994 is reported from three new localities in the TIWP and is now known from 13 chaetodontid species. Sequences from samples consistent with P. flindersi differed from those from P. oxleyi n. sp. in 11–12 base pairs. The host ranges of the two species overlap broadly. Neither species was found in French Polynesia but both were found at Swain Reefs on the Great Barrier Reef. Only one of the two species was found at each of the five other sites. Both species occur almost exclusively in specialist corallivores allowing the inference that the metacercariae occur in corals. Finally, a key to the species of Paradiscogaster is provided.     

The Hemiuroidea (Digenea) of pomacentrid fishes (Perciformes) from Heron Island,Queensland, Australia

The following species are described, figured and/or recorded from pomacentrid fishes from the vicinity of the southern Great Barrier Reef coral cay Heron Island, with some mention of comparative material from other host families and locations: Derogenes pearsoni n. sp. from Amblyglyphidodon curacao, Amphiprion akindynos, Plectroglyphidodon lacrymatus (type-host), Pomacentrus chrysurus, P. moluccensis, P. tripunctatus and Pomacentrus sp.; Derogenes pharyngicola n. sp. from Abudefduf whitleyi (type-host) and Plectroglyphidodon dickii; Lecithaster stellatus from Abudefduf sexfasciatus, A. whitleyi, Acanthochromis polyacanthus, Amblyglyphidodon curacao, Chrysiptera flavipinnis, Parma polylepis, Pomacentrus chrysurus, P. moluccensis, P. cf. nagasakiensis, P. cf. pavo, P. vaiuli, P. wardi, Seriola lalandi, Cheilinus diagrammus, Lethrinus miniatus and Choerodon cyanodus from Heron Island plus Acanthopagrus australis and Rhabdosargus sarba from Moreton Bay; Aponurus laguncula from Pomacentrus moluccensis plus Callionymus limiceps, Platycephalus endrachtensis and P. fuscus from Moreton Bay; Hysterolecitha nahaensis from Abudefduf bengalensis, A. sexfasciatus, A. whitleyi, Acanthochromis polyacanthus, Amblyglyphidodon curacao, A. leucogaster, Amphiprion akindynos, A. perideraion, Chromis atripectoralis, C. nitida, C. viridis, Chrysiptera flavipinnis, C. cf. rollandi, Dascyllus aruanus, D. reticulatus, Parma polylepis, Pomacentrus chrysurus, P. moluccensis, P. cf. nagasakiensis, P. nigromarginatus, P. cf. pavo, P. tripunctatus, P. wardi and Pomacentrus sp.; Hysterolecitha heronensis n. sp. from Pomacentrus philippinus (type-host), P. amboinensis, P. moluccensis, P. nigromarginatus and Pomacentrus sp.; Hysterolecitha sp. innom. from Parma polylepis; Thulinia microrchis n. comb. (new syns Hysterolecitha microrchis, H. xesuri, H. tinkeri, Thulinia tinkeri, H. sigani) from Abudefduf bengalensis, A. sexfasciatus, A. whitleyi, Acanthochromis polyacanthus, Amphiprion perideraion, Dascyllus aruanus, D. reticulatus, Dischistodus melanotus, Parma polylepis, Plectroglyphidodon dickii, Pomacentrus amboinensis, P. moluccensis, P. philippinus, P. taeniometopon, Pomacentrus sp. and Stegastes apicalis, plus Chaetodon citrinellus, C. kleinii, Chaetodontoplus meredithi, Lethrinus miniatus, Plectropomus leopardus, Siganus doliatus, S. lineatus and S. vulpinus; Leclthocladium sp. juv from Abudefduf whitleyi, Lecithochirium sp. (? ghanense-group) from Dascyllus aruanus; Lecithochirium sp. juv. from Abudefduf whitleyi; unidentified non-ecsomate hemiuroids from Chrysiptera cf. rollandi, Parma polylepis, Pomacentrus chrysurus, P. wardi and Stegastes apicalis.     

Syringophilid mites (Acari: Syringophilidae) associated with the rails (Aves: Rallidae) and a key to the species of the genus Rafapicobia Skoracki, 2011

The fauna of quill mites of the family Syringophilidae Lavoipierre, 1953 (Acari: Prostigmata Cheyletoidea) parasitising birds of the family Rallidae Vigors (Gruiformes) is updated. A new species, Rafapicobia melzeri n. sp. (subfamily Picobiinae), is described from four host species: Rallus aquaticus Linnaeus (type-host) from Germany, Pardirallus sanguinolentus (Swainson) from Chile, Porzana porzana (Linnaeus) from France and P. parva (Scopoli) from Kirghizia. The new species is most similar to R. lepidocolaptesi Skoracki & Solarczyk, 2012 but differs in the absence of agenital plates and the length ratios of setae ag2:g1 and vi:ve:si in females and in the punctate ornament on the hysteronotal and the pygidial shields in males. A key to the species of the genus Rafapicobia is proposed. This is the first record of a representative of the subfamily Picobiinae on gruiform birds. Additionally, new rallid hosts are reported for Charadriphilus ralli Skoracki & Bochkov, 2010 (subfamily Syringophilinae): Gallinula melanops (Vieillot) from Chile, Laterallus melanophaius (Vieillot) from Paraguay, and P. parva (Scopoli) from Kirghizia.     

Aspects of the feeding ecology of Sargochromis codringtonii in Lake Kariba, Zimbabwe

Sargochromis codringtonii has always been considered a good candidate for the biological control of snails. However, there is lack of data on the feeding ecology of this species. The diet of S. codringtonii was examined by an analysis of stomach contents. The food of adult S. codringtonii in Lake Kariba is dominated by prosobranch snails. Pulmonate snails form a small insignificant component of the diet of S. codringtonii , and the reasons for this are discussed. Electivity indices were used to investigate prey selection. S. codringtonii does not show a particular preference for any snail species. It feeds on any snail species that is readily available. A morphometrical analysis of the feeding structures of S. codringtonii showed that the fish is well adapted to handling a molluscivorous diet. The daily food consumption of S. codringtonii was estimated over different seasons using the Elliot & Persson (1978 ) model [ J. Anim. Ecol. 47. 977–991]. Estimates of food consumption indicate that the fish consumed 14.0% of their dry body weight per day in summer and this falls to 4.5% in winter. The low consumption of pulmonates means that S. codringtonii cannot be a successful biological control agent against the vectors of schistosomiasis.