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D I Gibson

Publications and source records attributed to D I Gibson.

At least 19 recordsLinked to original sources
PubMed2006

Diplectanocotyla Yamaguti, 1953 (Monogenea: Diplectanoidea) from Megalops cyprinoides (Broussonet) (Teleostei: Megalopidae) off Peninsular Malaysia.

Two known and two new species of Diplectanocotyla Yamaguti, 1953 (D. gracilis Yamaguti, 1953, D. megalopis Rakotofiringa & Oliver, 1987, D. langkawiensis n. sp. and D. parva n. sp.) were collected from Megalops cyprinoides (Megalopidae) off Langkawi, Kedah and Matang, Perak, Peninsular Malaysia. All four species possess similar types of sclerotised male and female reproductive structures and similar soft anatomical features. The squamodisc sclerites of all four species have spine-like projections with varying degrees of visibility and shapes (sharp-pointed to triangular). In D. megalopis and D. langkawiensis n. sp. the spines are sharp-pointed and distinct on sclerites from rows 5-6 onwards. In D. gracilis and D. parva n. sp. the sclerite spines are triangular, lightly sclerotised and occur on almost all of the sclerites. D. parva n. sp. has comparatively the smallest set of anchors, bars, squamodiscs and squamodisc suckers. The anchors and bars of the other three species are almost similar in overall size, and the main distinguishing feature is the relative lengths of the inner and outer roots of the ventral anchors. In D. gracilis the outer root is very much smaller than the inner root and they are disposed almost at a right angle to each other. In D. megalopis the outer root is usually about half the length of the inner root and the roots are inclined at c.60 degrees to each other. In D. langkawiensis n. sp. the roots are inclined at c.40 degrees degrees and the outer root is of a similar length or only slightly shorter than the inner root. The openings of the two squamodisc suckers of all four Diplectanocotyla species are surrounded by tiny scale-like spines. Bifid tegumental spines are found in the posterior region of all four species, differing only in their extent: in D. parva n. sp. the tegumental spines are only distributed in the peduncular region and not beyond, whilst in the other three species the tegumental spines extend from the posterior level of the testis to the end of the peduncle. An amended diagnosis of Diplectanocotyla and a key to its species are appended.

Animals↗
PubMed2006

Saturnius minutus n. sp. and S. dimitrovi n. sp. (Digenea: Hemiuridae) from Mugil cephalus L. (Teleostei: Mugilidae), with a multivariate morphological analysis of the Mediterranean species of Saturnius Manter, 1969.

Three species of the bunocotyline genus Saturnius Manter, 1969 are described from the stomach lining of mugilid fishes of the Mediterranean and Black Seas. Two of the species are new: S. minutus n. sp. occurs in Mugil cephalus off the Mediterranean coast of Spain; and S. dimitrovi n. sp., a parasite of M. cephalus off the Bulgarian Black Sea coast and the Spanish Mediterranean coast, was originally described as S. papernai by Dimitrov et al. (1998). In addition, S. papernai Overstreet, 1977 is redescribed from M. cephalus off the Spanish Mediterranean coast and from Liza aurata and L. saliens off the Bulgarian Black Sea coast. The three species are distinguished morphometrically using univariate and multivariate analyses. These results were verified using Linear Discriminant Analysis which correctly allocated all specimens to their species designations based on morphology (i.e. 100% successful classification rate) and assigned almost all specimens to the correct population (locality). The following variables were selected for optimal separation between samples: the length of the forebody, ventral sucker and posterior testis, the length and width of the posteriormost pseudosegment, and the width of the muscular flange at ventral sucker level.

Animals↗
PubMed2006

Robinia aurata n. g., n. sp. (Digenea: Hemiuridae) from the mugilid Liza aurata with a molecular confirmation of its position within the Hemiuroidea.

Robinia aurata n. g., n. sp. is described from Liza aurata (Mugilidae), the golden grey mullet, from the Ebro Delta, Spanish Mediterranean. The new genus differs from all other hemiurid genera in the combined possession of muscular flanges and a vestigial ecsoma. Within the Bunocotylinae, which currently accommodates 2 genera, Bunocotyle and Saturnius, the new genus exhibits a unique combination of blind caeca, Juel's organ, post-ovarian bulk of the uterus in the hind-body, and tegumental papillae surrounding the oral and ventral sucker apertures. Furthermore, Robinia n. g. differs from both Bunocotyle and Saturnius in the nature of the muscular extensions around the oral sucker, with the shape of a muscular belt in the latter and numerous muscular papillae in the former. The phylogenetic hypothesis for the Bunocotylinae developed from sequence data analyses based on partial lsrDNA and complete ssrDNA combined (22 species) and V4 domain of the ssrRNA gene (37 species) supports the erection of the new genus and confirms its position within the Hemiuroidea. Both molecular analyses confirmed the monophyly of the Hemiuroidea, its division into 2 major clades and the polyphyly of the Derogenidae, as in previous studies, and suggest that the Gonocercinae (with 2 genera, Gonocerca and Hemipera), may require a distinct familial status. Finally, there was poor support for the distinct status of the Lecithasteridae and Hemiuridae, following previous suggestions based on different sequence data sets. A key to genera of the Bunocotylinae is presented.

Animals↗
PubMed2004

A new species of Nasicola Yamaguti, 1968 (Monogenea: Capsalidae) from the nasal cavities of Thunnnus obesus and a redescription of N. klawei (Stunkard, 1962) from T. albacares off Brazil.

Two species of Nasicola Yamaguti, 1968 are described from the nasal cavities of tunas ( Thunnus spp.) from off the coast of Brazil: N. brasiliensis n. sp. from T. obesus (Lowe) and the type-species, N. klawei (Stunkard, 1962), from T. albacares (Bonn.). The new species is differentiated from N. klawei on the basis of the large number of testes and from N. hogansi Wheeler & Beverley-Burton, 1986 by its greater body-size, proportionately smaller haptor and smaller number of marginal spines. The host-specificity of Nasicola spp. is commented upon.

Animals↗
PubMed2001

Redescriptions of two echinostomes from freshwater fishes, with comments on Singhia Yamaguti, 1958 and Caballerotrema Prudhoe, 1960 (Digenea: Echinostomatidae).

The type-species of Singhia and Caballerotrema (Digenea: Echinostomatidae), parasites of freshwater fishes which have previously been assigned to the subfamily Singhiinae Yamaguti, 1958, are redescribed. One of the specimens of the type-series of Caballerotrema brasiliense Prudhoe, 1960 was identified as C. aruanense Thatcher, 1980. C. arapaimense Thatcher, 1980 is considered a species inquirenda. Himasthla piscicola Stunkard, 1960 is transferred to Caballerotrema as C. piscicola n. comb. The generic diagnoses of Singhia and Caballerotrema are redefined and Singhia is re-allocated to the Echinostomatinae Looss, 1899, the Singhiinae becoming a synonym of the latter.

Animals↗
PubMed2001

Metadena phoceae n. sp. (Digenea: Cryptogonimidae), a rectal parasite of the shore rockling Gaidropsarus mediterraneus (Teleostei: Lotidae) in the western Mediterranean.

Metadena phoceae n. sp. is described and figured in detail from the rectum of the shore rockling Gaidropsarus mediterraneus (Lotidae) in the Gulf of Marseilles and off Corsica. It is compared with other cryptogonimids occurring in Mediterranean and Black Sea fishes and is distinguished from its closest relatives, M. depressa (Stossich, 1883) and M. pauli (Vlassenko, 1931), which occur in sparid and sciaenid fishes, respectively, by both morphometrical and biological features. The host-specificity of cryptogonimids occurring in Mediterranean and Black Sea fishes is commented upon.

Animals↗
PubMed2001

Dactylogyridean monogeneans of the siluriform fishes of the Old World.

This is a catalogue and discussion of the known dactylogyridean monogenean genera of siluriform fishes of the Old World. Of a total of 38 nominal genera, only 19 are considered valid. Seventeen of these 19 genera are currently in the Ancyrocephalidae (containing the Ancyrocephalinae and Ancylodiscoidinae), whilst the other two (Neocalceostoma and Neocalceostomoides) are in the Neocalceostomatidae. The 17 genera are Anchylodiscus, Ancylodiscoides, Bagrobdella, Bifurcohaptor, Bychowskyella, Chauhanellus, Cornudiscoides, Hamatopeduncularia, Mizelleus, Paraquadriacanthus, Pseudancylodiscoides, Protoancylodiscoides, Quadriacanthus, Schilbetrema, Schilbetrematoides, Synodontella and Thaparocleidus. Clariotrema Long, 1981 and Neobychowskyella Ma, Wang & Li, 1983 are considered synonyms of Bychowskyella Akhmerov, 1952, Anacornuatus Dubey, Gupta & Agarwal, 1992 is considered a synonym of Quadriacanthus Paperna, 1961, Mizellebychowskia Gupta & Sachdeva, 1990 is considered a synonym of Neocalceostoma Tripathi, 1959 and Hargitrema Tripathi, 1959 is treated as a synonym of Hamatopeduncularia Yamaguti, 1953. It is proposed that the Ancylodiscoidinae be raised to family status within the order Dactylogyridea to accommodate these 17 'ancyrocephalid' genera from siluriforms, together with Malayanodiscoides and Notopterodiscoides from notopterids. A key and the diagnostic characteristics of the 19 recognised dactylogyridean genera from catfishes plus two from notopterids, together with a list of species and synonyms, are included. New combinations made in this work are Thaparocleidus avicularia (Chen, 1987) n. comb., T. calyciflorus (Chen, 1987) n. comb., T. choanovagina (Luo & Lang, 1981) n. comb., T. dissimilis (Chen, 1988) n. comb., T. leiocassis (Reichenbach-Klinke, 1959) n. comb., T. meticulosa (Chen, 1987) n. comb., T. parasoti (Zhao & Ma, 1999) n. comb., T. persculpus (Chen, 1987) n. comb., T. valga (Chen, 1987) n. comb. and T. wulingensis (Yao & Wang, 1997) n. comb. [all from Silurodiscoides] and Bychowskyella glyptothoraci (Ma, Wang & Li, 1983) n. comb. [from Neobychowskyella].

Africa↗
PubMed2000

Pseudorhabdosynochus spp. (Monogenea: Diplectanidae) from the gills of Epinephelus spp. in Brazilian waters.

Pseudorhabdosynochus sulamericanus n. sp. from the gills of Epinephelus niveatus has a reniform proximal region of the cirrus-bulb which is divided in four chambers and contains a large, round reservoir of the male accessory glands, a partly sclerotised vagina which is enclosed in a muscular funnel cap and squamodiscs with 15-16 open concentric rows of elements. P. beverleyburtonae (Oliver, 1984) is redescribed from E. marginatus with additional morphological data. These are the first reports of Pseudorhabdosynochus spp. in South American Atlantic waters, where the potentiality for the mariculture of Epinephelus spp. is currently being evaluated. Pseudorhabdosynochus hargisi (Oliver & Paperna, 1984) n. comb. is proposed for Diplectanum hargisi.

Animals↗
PubMed2000

A quantitative approach to the evaluation of the morphological variability of two echinostomes, Echinostoma miyagawai Ishii, 1932 and E. revolutum (Frölich, 1802), from Europe.

A comparative morphometric analysis was conducted on two European species of Echinostoma in order to examine the degree of the variability in the metrical characteristics of the adults and to assess their value in discriminating species. Adult E. miyagawai and E. revolutum, obtained experimentally, were compared using univariate and multivariate statistical analyses of 35 and 25 metrical characters, respectively. All subsets of worms of different ages represented homogeneous samples with respect to their morphometric characteristics; however, univariate analyses revealed significant differences in 22 and 23 variables between the corresponding age subsets of the two species, and it was found that the different allometric growth patterns contribute to this. The variables, body width at the posterior border of the ventral sucker, pharynx length and width, ovary length, testes length and width and length of the pre-ovarian region, exhibited isometric or positive allometric growth in E. miyagawai and negative allometry in E. revolutum. A cluster analysis based on 61 specimens and 25 variables separated E. revolutum and E. miyagawai unambiguously, producing an exact ordering of the specimens with respect to their identity and age. A forward stepwise discriminant analysis identified five variables (body width at the posterior border of ventral sucker, head collar width, length of oesophagus, width of ventral sucker and length of the pre-ovarian region) which yielded a 100% accurate classification of the two species. We suggest, therefore, that the morphometric characteristics of the adult worms should be used in studies attempting the identification of species or isolates of Echinostoma spp. More comparative data need to be gathered in order that the species boundaries within the 'revolutum' group be defined more accurately.

Analysis of Variance↗
PubMed2000

Re-validation of Echinostoma miyagawai Ishii, 1932 (Digenea: Echinostomatidae) on the basis of the experimental completion of its life-cycle.

The life-cycle of Echinostoma miyagawai, a Eurasian species closely related to E. revolutum, was completed in the laboratory, and the morphology of the larval stages and the adults obtained experimentally was studied. Planorbis planorbis and Anisus vortex were the first intermediate hosts in the brackish Lake Durankulak on the Bulgarian Black Sea coast. Characteristic features of the cercaria include: a prominent collar with 37 spines; a tail as long as the body and with seven conspicuous fin-folds, the two ventral fin-folds being very close to each other; and a specific number and distribution of both the para-oesophageal gland-cell outlets and sensilla. The adult is characterised by: a very elongate body with a constriction at the posterior border of the ventral sucker; a large head collar with relatively small spines; a spherical ventral sucker which is only about half the maximum body width; a long cirrus-sac reaching posteriorly dorsal to the middle of the ventral sucker; indented subglobular testes; and a vitellarium forming two lateral fields of follicles which are almost confluent in the post-testicular space. The species described in this study resembles E. miyagawai, as described by Kosupko, in the morphology of larval stages and both the site and the general morphology of the adults. It differs from both E. revolutum, as described by both Kanev and Nasincová, and E. echinatum (also referred to as E. lindoense and E. barbosai by Kanev). The re-examination of Kanev's voucher specimens from his experimental studies used in his delimitation of E. revolutum and E. echinatum showed that the specimens identified by him as E. revolutum represent two distinct forms which consistently differ both from each other and from the redescription of E. revolutum which was based upon them. It also revealed that a number of specimens were wrongly identified and erroneously treated as E. echinatum by Kanev and co-workers; these include members of different genera (Hypoderaeum and Echinoparyphium) and an Echinostoma species of the group possessing 47 collar spines. The relative merits of the features used by Kanev and co-workers in discriminating the closely related Echinostoma spp. are discussed in detail with respect to the experimental evidence provided by these authors.

Animals↗
PubMed2000

Pseudoterranova decipiens species A and B (Nematoda, Ascaridoidea): nomenclatural designation, morphological diagnostic characters and genetic markers.

Five genetically distinct and reproductively isolated species have been detected previously within the morphospecies Pseudoterranova decipiens from the Arctic-Boreal, Boreal and Antarctic. Morphological analysis was carried out on male specimens identified by genetic (allozyme) markers, allowing the detection of significant differences at a number of characters between two members of the P. decipiens complex, namely P. decipiens A and B. On the basis of such differences, the nomenclatural designation for the two species is discussed. The names Pseudoterranova krabbei n. sp. and P. decipiens (sensu stricto) are proposed for species A and B, respectively. Morphological and genetic differentiation between the two species is shown using multivariate analysis. Allozyme diagnostic keys for routine identification of the four members of the P. decipiens complex, namely P. decipiens (s.s.), P. krabbei, P. bulbosa and P. azarasi, irrespective of sex and life-history stage, are provided.

Animals↗
PubMed1999

Cercarial emergence of Ichthyocotylurus erraticus (Rudolphi, 1809), I. variegatus (Creplin, 1825) and Apatemon gracilis (Rudolphi, 1819) (Digenea: Strigeidae): contrasting responses to light:dark cycling.

Many digenean cercariae have been shown to emerge from their molluscan hosts with distinct shedding patterns that have enabled the discrimination of morphologically similar species, or even strains. In this study the cercarial emission patterns of three strigeid species, Ichthyocotylurus erraticus, I. variegatus and Apatemon gracilis, from experimentally infected natural hosts were found to exhibit rhythms that correlated with the light:dark cycle. Both Ichthyocotylurus spp. exhibited a diurnal pattern of release in which cercariae emerged during the light period. Each demonstrated a latent period before the liberation of large numbers of cercariae and yielded similar numbers of cercariae daily. These rhythms offered no means for the discrimination of these two morphologically similar species. A. gracilis cercariae demonstrated a very different circadian rhythm in which the majority emerged at the onset of darkness with no latent period, whereas the cercarial numbers released daily were far greater. Differences could be related to piscine host behaviour.

Animals↗
PubMed1999

A redescription of Pseudobacciger harengulae (Yamaguti, 1938) (Digenea: Faustulidae) from Sprattus sprattus phalericus (Risso) and Engraulis encrasicholus ponticus Alexandrov off the Bulgarian Black Sea coast, with a review of the genus Pseudobacciger Nahhas & Cable, 1964.

Pseudobacciger harengulae is recorded from the caeca of Sprattus sprattus phalericus and Engraulis encrasicholus ponticus (new host records) in the Black Sea (new geographical record) off the Bulgarian coast. This is the first record of a species of the genus Pseudobacciger in the Black Sea. An illustrated redescription on the basis of the Bulgarian material is presented. The specimens from the two hosts differ from one another in the shape of the arms of the excretory vesicle. A review of Pseudobacciger is presented; for each of the three species of the genus, data on their hosts, distribution, morphology and life-cycle (if known) are summarised.

Animals↗
PubMed1999

Echinorhynchus brayi n. sp. (Acanthocephala: Echinorhynchidae) from Pachycara crassiceps (Roule) (Zoarcidae), a deep-sea fish.

Echinorhynchus brayi n. sp. (Palaeacanthocephala: Echinorhynchidae) is described from Pachycara crassiceps (Roule) (Zoarcidae) from the Porcupine Seabight, Northeast Atlantic. The new species closely resembles E. canyonensis Huffman & Kliever, 1977, a parasite of a Pacific zoarcid, but has longer lemnisci, larger eggs and larger testes. E. brayi n. sp. can be readily differentiated from the ten other Echinorhynchus spp. recorded from deep-sea fishes (E. abyssicola, E. gadi, E. longiproboscis, E. malacocephali, E. melanoglaeae, E. muraenolepisi, E. petrotschenkoi, E. sebastolobi, E. trachyrinci and E. truttae), because it has fewer hooks per longitudinal row.

Acanthocephala↗
PubMed1999

Urotrematidae Poche, 1926 (Platyhelminthes: Digenea) in Chinese freshwater fishes.

The genera Sinineobucephalopsis and Sinogastromyzontrema are diagnosed and placed in the family Urotrematidae. Sinineobucephalopsis macrocirrus is redescribed from Glyptothorax fokiensis in Guangdong and Hunan provinces. Urotrema glyptothoraci is considered synonymous with Sinineobucephalopsis macrocirrus. The new combinations Sinineobucephalopsis postlecitha, Sinineobucephalopsis proeilecitha and Sinineobucephalopsis sinipercae are formed for species originally placed in Urotrema and Urotrematulum. Sinogastromyzontrema guangxiensis is redescribed from Sinogastromyzon wui in Guangxi Province. Urotrema parallelorchis is considered a synonym of Sinogastromyzontrema guangxiensis. A key to the species or species-complexes in the family Urotrematidae is given.

Animals↗
PubMed1999

Chalcinotrema thatcheri n. sp. (Digenea: Haploporidae) from Brazilian freshwater fishes, a redescription of C. ruedasueltensis Thatcher, 1978 and comments on the validity of the genus.

Chalcinotrema thatcheri n. sp. from the intestine of Schizodon knerii is described. It is most closely related in general morphology to C. salobrensis Freitas, 1947 and C. ruedasueltensis Thatcher, 1978, from which it differs, respectively, in: testis-size, the distribution of the vitelline follicles and the distance between the gonads; and body-size, egg-size, the extent of the caeca and the shape of the seminal vesicle. The holotype of C. ruedasueltensis is redescribed with original figures. Chalcinotrema Freitas, 1947, is considered a good genus distinct from Carassotrema Park, 1938, on the basis of the presence of uterine loops between the ovary and testis and its totally different geographical distribution. Carassotrema tilapiae Nasir & Gomez, 1976 is transferred to the former genus as Chalcinotrema tilapiae (Nasir & Gomez, 1976) n. comb.

Animals↗
PubMed1998

The application of chaetotaxy in the discrimination of Gyrodactylus salaris Malmberg, 1957 (Gyrodactylidae: Monogenea) from species of the genus parasitising British salmonids.

The chaetotaxy of argentophilic structures on three species of the monogenean genus Gyrodactylus was investigated in an attempt to distinguish species of this genus. Maps were prepared for Gyrodactylus salaris from Scandinavia and compared with two native species of Gyrodactylus parasitising salmonids in Britain, namely Gyrodactylus derjavini and Gyrodactylus truttae. The maps were subsequently refined and analysed for zones of homology and differentiation. The results demonstrate that G. salaris can be readily distinguished by this technique, which is, therefore, of great potential value in the identification of this notifiable pathogen. The key aggregations of sensilla discriminating G. salaris are, ventrally, the antero-ventral set, the medio-lateral set and the postero-lateral set, and, dorsally, the postero-dorsal set.

Animals↗