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Sciadicleithrum juruparii n. sp. is described from the gills of the Neotropical cichlid fish Satanoperca jurupari (Heckel) caught in the Guamá River, in the delta of the Amazon River, at Belém, Pará State, Brazil. Diagnostic characters of the new species are a basally articulated male copulatory organ with clockwise coils and an accessory piece; a ventral bar with a median process; similar hooklets; vagina in the form of a sclerotised tube; and a sinistral vaginal aperture with a sclerotised papilla lying in a small surface depression. It is the only species of Sciadicleithrum Kritsky, Thatcher & Boeger, 1989 with a medial projection on the ventral bar.  相似文献   

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The Scarce Chaser (Libellula fulva) is widespread in Europe and in many regions is relatively common. It is also abundant in the lake districts of western and northern Poland. Although the species frequently occurs in large numbers its biology is poorly known. Emergence of L. fulva was investigated in this study as a contribution to the life history of the species. Studies were carried out in the vicinity of Chojno (52°41′ N, 16°12′ E) on the edge of the Notecka Forest in 2003 and 2004. The stem habitat of the population is a stream with the adjacent swamps. Libellula fulva belongs to the spring species sensu Corbet (1999). The emergence of the studied population lasted 19 days (between 18 May and 5 June) and 31 days (between 13 May and 12 June) in 2003 and 2004, respectively. It was characterised by synchronous and, especially in the first phase, mass emergence. The high synchronisation is reflected in the fact that 50% of the population had emerged by the seventh (in 2003) and the fifth (in 2004) days of the process. This is vital to the imagines, which mature and return to the water body as soon as possible to reproduce. Timing of the end of emergence depends on atmospheric conditions during its duration and the conditions preceding the start of emergence on a given day. In the daily course there is a tendency for emergence to finish as soon as possible. Extension of the emergence is synonymous with increased mortality in the dragonfly population caused by predators.  相似文献   

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Patrick Scaps 《Hydrobiologia》2002,470(1-3):203-218
The common ragworm Hediste diversicolor inhabits the shallow marine and brackish waters in the North Temperate Zone of the Atlantic. This infaunal species builds U or Y-shaped burrows in the soft sediments. H. diversicolor is gonochoristic and remains atokous throughout its life. Due to the facility of harvesting of individuals by hand and their maintenance, this species represents a good biological material for experimental studies. In consequence, the common ragworm served as a model for endocrine control of reproduction in Polychaeta and played a fundamental role in the study of immune defence in Polychaeta.Life history characteristics (longevity, spawning season, feeding tactics and growth) and population dynamics (sex ratio, density and biomass) vary greatly according to geographical location of the populations. In addition, inter-population morphological, biochemical and physiological differences have been noticed in individuals from different areas and different environmental conditions in the same areas and could be related to the limited dispersal capacity of the species. H. diversicolor interacts with its environment. The construction of burrows by individuals increases the sediment–water interface. When they ventilate their burrows, individuals verticalize oxic zones into the sediment and promote microbial and meiofaunal growth alongside their burrows. Moreover, the common ragworm is a species of commercial interest because of its use as bait in recreational fishing and as food in aquaculture. In order to alleviate environmental pressure caused by excessive demand over optimal sustainable yield of bait fisheries, intensive aquaculture has been proposed. The common ragworm could be also used as biomonitor of pollution in estuarine ecosystems.  相似文献   

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Oöcysts of Eimeria whitakeri n. sp. are described from the faeces of the least shrew, Cryptotis parva (Insectivora: Soricidae), from Texas, USA. The oöcysts are spherical to subspherical, 17.4 × 16.4 (15–19 × 13–18.5) μm, with a bi-layered wall; their shape-index (length/width) is 1.1 (1.0–1.2). A micropyle and oöcyst residuum are absent, but a large polar granule is present. The sporocysts are ovoidal, 11.2 × 7.5 (9.5–12 × 6.5–8) μm, with Stieda and substieda bodies; their shape-index is 1.5 (1.4–1.6). The sporozoites each possess both anterior and posterior refractile bodies.  相似文献   

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The timely characterization of high-altitude freshwater habitats allows an assessment of the diversity of its biota and provides the basis for monitoring community change. In this study, we investigate the Cladocera fauna of 29 water bodies (pools, freshwater lakes, and surrounding swamps sampled at various occasions between 2005 and 2009) in the Rwenzori Mountains (Uganda, D. R. Congo), which are part of the East African Sky Island Complex. All sites except one are located above 3700 m altitude. We include notes on the morphology, taxonomy, distribution, and ecology of each recorded taxon and describe a new species of the Alona rustica-group (Alona sphagnophila n.sp.; Chydoridae). We found 11 species of which seven are restricted to Lake Mahoma, the lowest lake in our study area (2990 m) (Alona affinis barbata, A. intermedia, Alonella exisa, Alonella nana, Daphnia cf. obtusa, Pleuroxus aduncus) and/or Lake Bujuku (Daphnia cf. curvirostris, P. aduncus) (3900 m). Two taxa (Ilyocryptus cf. gouldeni, A. sphagnophila n.sp.) are restricted to Carex/Sphagnum bogs surrounding lakes in the afroalpine zone. Pigmented populations of Chydorus cf. sphaericus occur in all the sites. It is the only cladoceran species surviving the extreme alpine and nival conditions in the Rwenzori. The species is joined by A. guttata at locations at lower altitudes (ca. 3000–4000 m), present in about half of the sites. The Rwenzori Cladocera fauna is characterized by a strong extratropical temperate component and a low level of speciation/endemism. Harboring an impoverished boreal cladoceran community, Lake Mahoma is given closer attention. At 2990 m, the lake is a cold-temperate aquatic island in the tropics and may function as a stepping stone for Palaearctic taxa. We introduce a new term for high-altitude, cold-water habitats in the tropics, which act as climatic islands for extratropical freshwater faunas, Löffler Islands, in honor of Dr Heinz Löffler. In comparison to surveys in 1961, we list five new records in Lake Mahoma, which could indicate cladoceran community changes over the past few decades at ca. 3000 m in the Rwenzori. Since the species distributions correlate to temperature and catchment properties of the lakes, the Rwenzori cladoceran fauna can be expected as sensitive indicators for local changes.  相似文献   

7.
Beveridge  Ian  Sukee  Tanapan  Jabbar  Abdul 《Systematic parasitology》2021,98(5-6):679-695
Systematic Parasitology - Rugopharynx australis (Mönnig, 1926) (Nematoda: Strongyloidea) is redescribed based on specimens from the type host, Osphranter rufus (Desmarest), together with...  相似文献   

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The genus Lasinus Sharp, 1874 of the Pselaphodes complex of genera (Pselaphitae: Tyrini: Tyrina) is revised. The three so far known species, Lasinus mandarinus Raffray, 1890, Lasinus monticola Sawada, 1961 and Lasinus spinosus Sharp, 1874 are redescribed. Eight new species, Lasinus sinicus sp. n. from China, Lasinus mikado sp. n., Lasinus yamamotoi sp. n., Lasinus inexpectatus sp. n., Lasinus yakushimanus sp. n., Lasinus amamianus sp. n., Lasinus saoriae sp. n., and Lasinus okinawanus sp. n. from Japan, are described. And all species are illustrated. Lectotypes are designated for Lasinus mandarinus and Lasinus spinosus. An identification key to species of the genus Lasinus is provided.  相似文献   

10.
Pharyngodon medinae García-Calvente, 1948 (Nematoda: Pharyngodonidae) is redescribed from Podarcis pityusensis (Bosca, 1883) (Sauria: Lacertidae) of the Balearic Islands (Spain) and confirmed as a member of the genus Skrjabinodon Inglis, 1968. A systematic review of S. medinae and closely related species is also given. Parathelandros canariensis is referred to Skrjabinodon as a new combination and Parathelandros Magzoub et al., 1980 is dismissed as a junior homonym of Parathelandros Baylis, 1930.  相似文献   

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Procamallanus (Spirocamallanus) chetumalensis n. sp. is described from the stomach and intestine of the Mayan sea catfish Ariopsis assimilis (Günther, 1864), from the Bay of Chetumal, Quintana Roo, México. It is characterized by bifurcate deirids; males have 3 pairs of preanal papillae, 6 pairs of postanal papillae, 2 pairs of transverse elongate adanal papillae surrounding the cloacal aperture, wide caudal alae, spicules of unequal length, and a gubernaculum, and females have a rounded tail bearing a digit-like process terminating in 2 spines. This is the seventh Procamallanus (Spirocamallanus) species reported from fishes in Mexico and the first one recorded in sea catfishes of the Ariidae.  相似文献   

13.
Two new species of Demidospermus Suriano, 1983 and a new genus, Pseudovancleaveus, and species are described from the gills of Iheringichthys labrosus (Pimelodidae). The fishes were collected from the upper Paraná River floodplain, Brazil. D. mandi n. sp. is characterised by the distal region of the copulatoty organ having an expanded bulb and D. labrosi n. sp. by the copulatory organ having a funnel-shaped proximal extremity. The latter species also has an accessory piece comprising a variable sheath enclosing the distal shaft of the copulatory organ and two anterolateral structures resembling irregular spheres. Pseudovancleaveus paranaensis. n. g., n. sp. is characterised by a sinistral vagina, overlapping gonads, a copulatory ligament, anchors without a fold on the base and hooks with slightly inflated shanks. A new combination, Pseudovancleaveus platensis, is proposed for Vancleaveus platensis Suriano & Incorvaia, 1995.  相似文献   

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Lutzomyia (Lutzomyia) falquetoi, sp. nov. (Diptera: Psychodidae, Phlebotominae) is described from the state of Espírito Santo, Brazil. This new species belongs to the series longipalpis and is easily distinguished from the other members of this taxon by the presence of five well-developed spines and a pre-apical spiniform bristle on the gonostyle as well as nine bristles on the basal tuft of the gonocoxite.  相似文献   

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Triloculotrema japanicae n. g., n. sp. (Monogenea: Monocotylidae: Merizocotylinae) is described. The parasite inhabits the olfactory sacs of the Japanese topeshark Hemitriakis japanica (Carcharhiniformes: Triakidae), and possesses a distinctive haptor with only three loculi. Some comments are made on the evolution of monocotylid monogeneans.  相似文献   

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Systematic Parasitology - Megalodoras uranoscopus (Eigenmann & Eigenmann) (Siluriformes, Doradidae) (the giant-talking catfish or the giant-raphael catfish), from the...  相似文献   

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