<Emphasis Type="Italic">Gyrodactylus thlapi</Emphasis>n. sp. (Monogenea) from <Emphasis Type="Italic">Pseudocrenilabrus philander philander</Emphasis> (Weber) (Cichlidae) in the Okavango Delta,Botswana

A new species of Gyrodactylus von Nordmann, 1832 and the first monogenean reported from Botswana is described from the cichlid Pseudocrenilabrus philander philander,bringing the number of gyrodactylids described from the African Continent to 18. Gyrodactylus thlapi n. sp. can be readily discriminated from the other described species almost exclusively by the shape of its hamuli, which have short roots and large, elongate ventral bar attachment points with the dorsal bar attachment point, demarcating the junction between the hamulus shaft and the root, positioned at the anterior terminus of the attachment plane. The marginal hooks of G. thlapi n. sp., which most closely resemble those of G. groschafti Ergens, 1973, are compared and discussed.     

Description of Gyrodactylus banmae n. sp. (Monogenea,Gyrodactylidae) parasitic on zebrafish,Danio rerio

A new species of Gyrodactylus was described on the body surface of zebrafish (Danio rerio) in China. Basing on morphological characteristics and ITS sequence, we identified the parasite as a new member of the Gyrodactylus-wageneri group. Morphologically, Gyrodactylus sp. nov. is greatly similar to “G. zebrae”, another species parasitic on zebrafish: both have moderately stout hamulus, marginal hook sickle with a prominent heel and toe, as well as a curved blade. However, distinct haptoral shape differences were detected between these two species. The dorsal bar is straight in Gyrodactylus sp. nov. but strongly curved in “G. zebrae”, and the sickle shaft in Gyrodactylus sp. nov. is approximately perpendicular to the base, but in “G. zebrae” it is slanted downwards. The ITS1-5.8S-ITS2 sequence also indicate that Gyrodactylus sp. nov. exhibits the highest similarity to “G. zebrae”: 95.7% sequence identity suggests interspecific differentiation. Phylogenetic analysis of the ITS1-ITS2 sequence showed that Gyrodactylus sp. nov. formed a sister clade with “G. zebrae”, and exhibited a relatively close phylogenetic relationship with G. kobayashii, G. gurleyi, and G. longoacuminatus, all of which parasitise on goldfish, Carassius auratus. To test the susceptibility of zebrafish and goldfish to the Gyrodactylus sp. nov., ten gyrodactylids were inoculated to the caudal fin of zebrafish and goldfish. The gyrodactylids exhibited the ability to attach themselves to the goldfish, and some gyrodactylids reproduced a few days after the inoculation. On day 9, however, the mean abundance sharply decreased to zero on goldfish and increased to more than 30 on zebrafish. The result suggested that golfish is an unsuitable host for Gyrodactylus sp. nov. Therefore, on the basis of morphology, molecular sequence similarity, and host susceptibility, we conclude that the gyrodactylid found on the zebrafish is a new species, which we named Gyrodactylus banmae.     

Taxonomy and host-specificity of Gyrodactylus aideni n. sp. and G. pleuronecti (Monogenea: Gyrodactylidae) from Pseudopleuronectes americanus (Walbaum) in Passamaquoddy Bay, New Brunswick, Canada

Wild and cultured winter flounder Pseudopleuronectes americanus (Walbaum) from Passamaquoddy Bay were surveyed for species of Gyrodactylus Nordmann, 1832. Two species were found: G. pleuronecti Cone, 1981 and G. aideni n. sp, both members of Malmberg’s ‘groenlandicus group’. Although the hard parts in the haptor are very similar in the two species, hamuli of G. aideni are consistently shorter than those of G. pleuronecti. The two species differed by 35 base pairs in the ITS 1, 5.8 and ITS 2 region. A BLAST search identified a variety of species of Gyrodactylus from marine fishes in the Atlantic Ocean as closest matches, indicating the ‘groenlandicus group’ is part of a major marine lineage within Gyrodactylus (sensu lato) that has successfully radiated among coastal percid, pleuronectid, cottid and anarhichadid fishes. Exposure experiments suggested that winter flounder is the primary host of both species of parasites and that three other pleuronectid species in the bay may potentially serve only as occasional transport hosts.     

Gyrodactylus gemini n. sp. (Monogenea: Gyrodactylidae), a parasite of Semaprochilodus taeniurus (Steindachner) from the Venezuelan Amazon

Gyrodactylus gemini n. sp. (Monogenea, Gyrodactylidae) is described from the surface of the body and fins of the fish Semaprochilodus taeniurus (Steindachner) imported into Britain from the Venezuelan Amazon. The new species differs from other species of the genus, including those described from South and Central America, by having: (i) stout hamuli with straight shafts and diverging roots; (ii) marginal hooks with the sickle length larger than the width; (iii) a dorsal bar without a medial constriction; (iv) a rectangular ventral bar with short processes; (v) a triangular ventral bar membrane; and, most obviously, (vi) at least two generations which can develop two embryos simultaneously. This is the first known species of the genus Gyrodactylus from the Venezuelan Amazon and the first record of the subgenus Gyrodactylus (Gyrodactylus) from South America.     

Parasites of the nine-spined stickleback Pungitius pungitius (L)

Eleven species of parasite are reported from the nine-spined stickleback Pungitius pungitius (L). Nine of these, namely, Trichodina domerguei, T. tenuidens, Vorticella sp., Epistylis?, Diplostomum spathaceum, Cryptocotyle lingua, Proteocephalus filicollis, Schistocephalus solidus and glochidia of Anodonta cygnea, are new host records for Great Britain. Gyrodactylus spp. and Thersitina gasterostei were also found.     

Two new species of Gyrodactylus von Nordmann, 1832 from Profundulus oaxacae (Pisces: Profundulidae) from Oaxaca,Mexico, studied by morphology and molecular analyses

In the present study, two new species of Gyrodactylus are described from Profundulus oaxacae, a fish endemic to the Pacific slope of Oaxaca State, Mexico. Fishes were collected within their distribution range in 5 localities in the Atoyac-Verde River. Gyrodactylus montealbani n. sp. and G. zapoteco n. sp. were erected and characterized morphologically (sclerites of the attachment apparatus and the male copulatory organ) and molecularly (sequences of the Internal Transcribed Spacer region of rDNA). The haptoral sclerites of the new species are similar to those of Gyrodactylus iunuri and Gyrodactylus tepari, both recently described from the goodeid fish Goodea atripinnis, from the Mexican States of Jalisco and Querétaro, respectively; and to Gyrodactylus xtachuna described from the poeciliid Poeciliopsis gracilis in Veracruz State, Mexico – nonetheless, these species can all be discriminated based on their marginal hook morphology. Specimens of G. montealbani n. sp. and G. zapoteco n. sp. were sequenced, and were aligned with sequences of 25 other Gyrodactylus spp. Both Maximum likelihood and Bayesian inference analyses indicated that the two new species are members of independent, well-supported lineages – these are the first Gyrodactylus species described from Profundulus oaxacae.     

Gyrodactylus quadratidigitus n. sp. (Monogenea: Gyrodactylidae), a parasite of the leopard-spotted goby Thorogobius ephippiatus (Lowe) from the south-western coast of the UK

Gyrodactylus quadratidigitus n. sp. (Monogenea, Gyrodactylidae) is described from the gills, fins and skin of Thorogobius ephippiatus (Lowe) (leopard-spotted goby) from Portland Castle Bay, Dorset, UK. G. quadratidigitus n. sp. most closely resembles the species ofGyrodactyluspreviously described by Geets from Pomatoschistus microps(Krøyer) in the approximate shape and size of the attachment hooks but can be readily distinguished from other species of the genus by the distinctive square shape of the toe region of the marginal hook sickle, the anteriorly positioned cirrus bulb and the unusually short intestinal crura which extend only as far as the level of the testes.     

Morphology and molecular taxonomy of Gyrodactylus jennyae n. sp. (Monogenea) from tadpoles of captive Rana catesbeiana Shaw (Anura), with a review of the species of Gyrodactylus Nordmann, 1832 parasitising amphibians

Gyrodactylus jennyae n. sp. is described from the body surface and mouthparts of tadpoles of the bullfrog Rana catesbeiana Shaw imported presumably from Missouri, USA, into a federal government facility in Moncton, New Brunswick, Canada. Its morphology resembles most closely that of G. chologastris Mizelle, Whittaker & McDougal, 1969 described from two amblyopsids (blind cave fishes) in Kentucky and North Carolina. Both species have long slender hamuli, a ventral bar with a relatively long membrane and small anterolateral processes, a cirrus with two rows of small spines and marginal hooks with a well-developed sickle heel and short handle. The two species differ morphologically; G. jennyae has a marginal hook sickle with a more pronounced heel than that found in G. chologastris. A BLAST search using a 945 base pair sequence that included the nuclear ribosomal DNA internal transcribed spacers 1 and 2 and the 5.8S rRNA gene from G. jennyae n. sp. showed that the overall similarity with other Gyrodactylus sequences on GenBank was relatively low. The ITS1 region was similar to that of G. misgurni Ling, 1962; however, no ITS2 and 5.8S rRNA sequences are available for that species. A separate search using 5.8S sequences revealed that G. markakulensis Gvosdev, 1950 and G. laevis Malmberg, 1957 were the closest to G. jennyae (1 and 2 bp differences, respectively). These species are parasites of cyprinids (or their predators) and are similar to G. jennyae and G. chologastris in having a double row of small hooks on the cirrus and overall similar morphologies of the haptoral hard parts. There are now five species of Gyrodactylus described exclusively from amphibians and this appears to have involved at least three separate host-switches from fishes.     

Goussia girellae N. Sp. (Apicomplexa: Eimeriorina) in the Opaleye,Girella nigricans1

ABSTRACT Goussia girellae n. sp. is described from the opaleye fish, Girella nigricans. Merogonic stages were observed in the apices of intestinal epithelial cells, in the lamina propria, and in extra-intestinal sites including liver, gills, and spleen. Gamonts were observed in the intestinal epithelial cells. Only unsporulated oocysts were detected in the intestine, and sporulation occurred when feces containing oocysts were incubated for 48 h in seawater at 21°C. Oocysts are elongated (24.8 × 14.7 μm) with a wall about 200 nm thick and have no residuum, micropyle, or polar granule. Sporocysts are ellipsoid (8.5 × 4.5 μm), have a thin two-layered wall approximately 30 nm thick, and consist of two valves joined by a suture. Although moribund opaleye were also infected with Gyrodactylus sp., Cryptobia sp., Cardicola sp., and epitheliocystis organisms (chlamydia), all fish were heavily infected with G. girellae and morbidity was thus attributed to the coccidium.     

Multivariate analyses of morphometrical features from Gyrodactylus spp. (Monogenea) parasitising British salmonids: Light microscope based studies

Species determination within the genus Gyrodactylus Nordmann, 1832 is based upon subtle differences in marginal hook morphology and has long posed taxonomic problems. This study uses univariate and multivariate analyses in an attempt to elucidate the Gyrodactylus species parasitising British salmonids. A total of 389 parasites were collected at 69 of 227 localities sampled throughout the British Isles from four salmonid host species, Salmo salar, Salmo trutta, Oncorhynchus mykiss and a limited number of Salvelinus alpinus. A small number of known species of Gyrodactylus from outside the UK were also added to the data set. Morphometric data on the sclerites were collected from slide preparations of Gyrodactylus using light microscopy. Univariate statistics were used to select 11 of the 18 useful morphometric features defined by Malmberg (1970) on the basis of those with the smallest natural variability and/or measurement error. The data, relating to the 11 variables chosen, were then analysed using principal components analysis (PCA) to describe the forms present. Initial outliers included foreign species of Gyrodactylus and an accidental infection by a gasterosteid form. Two major groups were resolved: one on S. salar and O. mykiss, the specimens from which resembled G. derjavini Mikailov, 1975 and G. caledoniensis Shinn et al. in press; and one on S. trutta, which was identified as G. truttae Gläser, 1974. The analysis, in addition to showing which were useful morphometric features, also demonstrated the limitations of data obtained from the smallest features when using the light microscope.     

The high‐Andean Jivarus Giglio‐Tos (Orthoptera,Acridoidea, Melanoplinae): systematics,phylogenetic and biogeographic considerations

The high‐Andean genus Jivarus Giglio‐Tos from Ecuador, Colombia and Peru is revised. Morphological cladistic analysis indicated that Jivarus montanus and the new species digiticercus sp.n. and rugosus sp.n. must be treated as a separate genus, Maylasacris gen.n. The remaining species included in the analysis are assigned to the genus Jivarus, for which the following six species groups are identified: americanus group, antisanae group, carbonelli group, cohni group, pictifrons group and jagoi group. Twenty‐nine species are recognized for Jivarus, with ten described as new: J. rectus sp.n. , J. megacercus sp.n. , J. spatulus sp . n. , J. auriculus sp.n. , J. riveti sp.n. , J. sphaericus sp.n. , J. discoloris sp . n. , J. profundus sp.n. , J. ronderosi sp.n. and J. guarandaensis sp.n. The following new synonymies are proposed: Jivarus albolineatus Ronderos with J. antisanae (Bolivar) syn.n. , J. cerdai Ronderos and J. osunai Ronderos with J. alienus (Walker) syn.n. , and J. rubriventris Ronderos with J. ecuadorica (Hebard) syn.n. ; the new combinations Jivarus ecuadorica (Ronderos) comb.n. and Maylasacris montanus (Ronderos) comb.n. are proposed. Keys to the species of the genera and a review of the morphological characters defining the taxa are provided. Patterns of distribution of the clades coincide with the geography of the northern Andes of Colombia and Ecuador. Areas of endemism of the Jivarus species groups and Maylasacris are delimited by both the high‐altitude curves, including transverse zones, and the drier climates of the intra‐Andean valleys, clearly indicating recent, post‐glacial palaeogeography, as shown also in vegetation distributions. This paper has been formatted with many embedded links to images of type and paratype specimens, maps based on geo‐referenced specimen data and species keys available on the Orthoptera Species file online ( http://orthoptera.speciesfile.org ).     

An SEM study of the haptoral sclerites of the genus Gyrodactylus Nordmann, 1832 (Monogenea) following extraction by digestion and sonication techniques

Techniques for the preparation of haptoral sclerites of Gyrodactylus species for scanning electron microscopy are described. Enzymatic digestion using pepsin allows fresh, frozen and alcohol-fixed material to be examined, but some sclerites, such as the dorsal and ventral bars, are lost. Sonication of fresh and frozen material retained these accessory bars, including the ventral bar membrane, the guard or sickle filament loop on the marginal hooks and even on some occasions ligaments associated with the sclerites. The sclerites of Gyrodactylus spp. from Gasterosteus aculeatus (L.) (three-spined stickleback), Oncorhynchus mykiss (Walbaum) (rainbow trout) and Salvelinus alpinus (L.) (charr) are described from SEM observations following the use of these preparation techniques, and the articulation between the hamuli and bars is commented upon.     

Lycophytes from the Middle Triassic (Anisian) locality Kühwiesenkopf (Monte Prà della Vacca) in the Dolomites (northern Italy)

Abstract: Generally, lycophytes are not well represented in Anisian floras. Nonetheless, four different genera, each with one species, have been distinguished in the Anisian flora from Kühwiesenkopf (Monte Prà della Vacca), Italy. They were well preserved and yielded leaf cuticles in all four taxa and in situ spores in two of them. Lycopia dezanchei gen. et sp. nov. is the most common form; it is characterized by a dichotomising creeping prostrate rhizome (representing the primary shoot axis) from which arise aerial axes, apically bifurcated and covered with bundles of long leaves. This taxon cannot be attributed to any of the lycophyte orders, but most resembles Lycopodiales. Two representatives of the Isoetales have been found, of which Isoetites brandneri sp. nov. is abundant. This species is characterized by a short stem, which is unusual for this genus. In situ immature microspores and megaspores were found in some specimens. Lepacyclotes bechstaedtii sp. nov. has a quadrilobe corm with fertile scales inserted in whorls or slightly helicoidally. Short sterile leaves arise distally from the corm in some specimens. Selaginellales are very rare in the flora; Selaginellites leonardii sp. nov. is represented by a strobilus that yielded both micro‐ and megaspores. Some sterile fragments have been found associated, but never in organic connection.     

An experimental test of antagonistic effects of competition and parasitism on host performance in semi‐natural mesocosms

The mechanisms by which parasites can mediate the interactions between species have received increased interest in recent years. Nonetheless, most research has focused on the role of shared parasites as mediators of interspecific competition. Here, we explore the relative effects of Gyrodactylus specialist ectoparasites of Trinidadian guppies Poecilia reticulata on competition between their host and juveniles of the killifish Rivulus hartii. In mesocosms that replicate natural streams, we exposed guppies to only competitors, to only parasites, to both parasites and competitors, or the absence of both. Consistent with previous studies, we found that female guppies grew significantly less where only Gyrodactylus were present, and this was regardless of infection status or parasite load. Surprisingly, this effect of Gyrodactylus on the growth of female guppies was greatly reduced when both parasites and competitors were present in the mesocosms. We conclude that guppies can mediate the effects of Gyrodactylus on competition with Rivulus, by adaptively fine‐tuning their phenotype when simultaneously facing multiple enemies.     

Trois nouvelles especes du genre mixtacandona (ostracoda,cyprididae, candoninae)

The authors describe Mixtacandona elegans n. sp.,M. pietrosanii n. sp., M. tabacarui n. sp. and present new data on the systematics and biogeography of the following Mixtacandona groups: ljovuschkini,hvarensis and riongessa. Mixtacandona elegans n. sp. belongs to the group ljovuschkini. The carapace is very elongated and has markedly assymetrical valves. The species has been found in a porous aquifer in southeastern Bulgaria. M. pietrosanii n. sp. belongs to the group hvarensis. The 3rd antennular segment and the 2nd endopodial segment of the cleaning leg have each two setae. The species lives in porous aquifers in the Danube plain in Roumania. M. tabacarui n. sp. (gr. riongessa) has a triangular left valve with a pointed dorsal protuberance. The species has been found in wells fed by karstic water in southern dobrodgea (Roumania), on the Black Sea coast.     

Morphological and molecular characterization of three new species of Gyrodactylus (Monogenea: Gyrodactylidae) infecting Sicydium salvini (Teleostei: Gobiidae) in Mexican rivers draining into the Pacific Ocean

The genus Gyrodactylus von Nordmann, 1832 is one of the most diverse within the class Monogenea; it contains mainly parasites of freshwater and marine teleost fishes. Around 40 species of Gyrodactylus have been described from gobiid fishes; mainly in Europe, as only two species are known from the Americas. In this study, we describe three new gyrodactylids from the body surface and fins of the goby Sicydium salvini (Gobiidae, Sycydiinae), which has a wide distribution on the Pacific coast, from Mexico to Panama. We describe Gyrodactylus oaxacae n. sp., G. atoyacensis n. sp. and G. salvini n. sp. collected from rivers draining to the eastern Pacific in the state of Oaxaca, Mexico. Morphologically, G. atoyacensis n. sp. and G. salvini n. sp. are very similar, and both are easily differentiated from G. oaxacae n. sp. Phylogenetic hypotheses based on sequences of the Internal Transcribed Spacers (ITS1–5.8S-ITS2 rDNA) and the D2 + D3 domains of the large ribosomal subunit (28S rDNA) support the erection of the three new taxa; and suggest that G. atoyacensis n. sp. and G. salvini n. sp. are sister species. These gyrodactylids are the first monogeneans described from gobies of the genus Sicydium in Mexico.     

Four new xarifiid copepods (Poecilostomatoida) associated with the scleractinian coral <Emphasis Type="Italic">Pavona</Emphasis><Emphasis Type="Italic">explanulata</Emphasis> (Lamarck) from off Taiwan

Four new xarifiid copepods are described. They were found in association with the scleractinian coral Pavona explanulata (Lamarck) occurring in shallow water reefs off Yenliao in northern Taiwan. The four species are: Xarifia capillata n. sp., X. parva n. sp., X. pavonae n. sp. and X. taiwanensis n. sp. They were found together in a single washing of the host coral. Previously, 13 species of copepods have been found in association with nine species of Pavona Lamarck. More than half (7/13) of these symbionts are members of Xarifia Humes, 1960.