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1.

Cucullanus tunisiensis sp. nov., (Nematoda: Cucullanidae), collected from the intestine of the white grouper Epinephelus aeneus from waters off the coast of Tunisia is described based on light and scanning electron microscopic observations. The new species is characterized by the presence of lateral alae, ventral sucker, long unequal spicules (left spicule 2474-2789 μm long, right spicule 2357-2518 μm long). This is the sixth nominal species of the genus Cucullanus Müller, 1777 and the first representative of this genus infecting fishes of Serranidae family reported from Tunisian waters.

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2.
Goezia moraveci n. sp. is described from light microscope and scanning electron microscope studies of the specimens recovered from the freshwater fish Mastacembelus armatus from West Bengal, India. G. moraveci differs from other species of the genus in having a small body size, the excretory pore posterior to the level of the nerve-ring, a very short, wide intestinal caecum and a long ventricular appendage (ratio 1: 6–15), a different number and arrangement of caudal papillae, and cuticular spines surrounding the bases of the caudal papillae. This represents the first species of the genus from a piscine host in India.  相似文献   

3.
The leptocerid trichopteran genus Notalina is recorded from the South American continent for the first time. Seven new species are described in it and placed in a new subgenus, Neonotalina: N.brasiliana, N.morsei, N.cipo and N.hamiltoni from southeastern Brazil, comprise the brasiliana species-group, and N.roraima from Venezuela, N.nanay from Peru and N.matthiasi from Colombia form the roraima species-group. Notalina (Neonotalina) is identifiable by the presence of a long, slender baso-mesal process on the male inferior appendage. The two species-groups may be distinguished by the morphology of the male phallus. The historical biogeography of the genus in South America is discussed.  相似文献   

4.
The bembrid genusBembras Cuvier is reviewed. Five species,B. japonica Cuvier,B. adenensis Imamura & Knapp and three undescribed species, were assigned to the genus. Type species of the genus,Bembras japonica is redescribed on the basis of 36 specimens including the holotype, and three new species,B. macrolepis, B. longipinnis andB. megacephala, previously misidentified asB. japonicus, are also described on the basis of specimens collected from Australia and Indonesia.Bembras macrolepis differs from its congeners by having large body scales, a long pectoral fin with 17–19 rays and a dark blotch on slightly upper portion to middle of margin, 14–15 anal-fin rays, small head and orbit, and caudal fin with a broad vertical dark band near posterior margin.Bembras longipinnis is distinguished from other members of the genus by having a slightly long pectoral fin with 17–19 rays and lacking a small black blotch near tip of upper rays, caudal fin with a large dark spot most intense in lower lobe, 1–2 gill rakers on upper gill arch, 13–14 anal-fin rays, slightly elong ated head and small orbit.Bembras megacephala is characterized by the following combination of characters: caudal fin with several irregular narrow vertical dark bands, small orbit, pectoral fin with 19–20 rays and lacking a small black blotch near tip of upper rays, head elongate, 2–4 gill rakers on upper gill arch, 15 anal-fin rays and small body scales. A key separating the five species ofBembras is given.  相似文献   

5.
A new Heterorhabditis species was isolated from nymphal stages of the seasonal cicada Diceroprocta ornea (Walker) in an asparagus field in the state of Sonora, Mexico. Concomitantly, another isolate of the same nematode species was also collected from an oak woodland habitat in the Chiricahua mountain range in southeastern Arizona. Morphological and molecular studies together with cross-hybridization tests indicate these two isolates are conspecific and represent a new undescribed Heterorhabditis sp. This new species is distinguished from other species in this genus by a combination of several qualitative and quantitative morphological traits. Key diagnostic features include: presence of a pronounced post-anal swelling in the hermaphrodite; male with nine pairs of bursal rays, with pairs 4 and 7 bent outwards and one pair of papillae placed on the cloacal opening, value of D% (average: 79); infective juveniles with a well developed cuticular tooth, long tail (average: 105 μm) and values of D% (average: 90) and E% (average: 99). In addition to these diagnostic characters, cross-hybridization tests between the new species with H. bacteriophora and H. mexicana yielded no fertile progeny. Comparison of ITS rDNA sequences with other available sequences of described species depicted the two isolates as a new species. Phylogenetic analysis of these sequence data placed H. sonorensis n. sp. as a member of the indica-group.  相似文献   

6.
Elasmobranch fossils recovered from the Fishburne Formation (lower Eocene/Ypresian) of Berkeley County, South Carolina, USA, include species from four genera of sharks and six genera of rays. Of particular interest was the recovery of multiple isolated teeth from a new genus and species of the cownosed ray family Rhinopteridae, which is the focus of this study. The unique crown morphology separates this genus and species from Rhinoptera. Eorhinoptera grabdai, gen. et sp. nov., is represented by small, bar-shaped teeth in the shape of greatly elongated hexagons. These teeth are the isolated elements of a dental plate. The holotype, with 12 wide root lobes, is the most elongated in the sample being 1 cm long and 1.5 mm wide, indicating an origin in the central region of the plate. Paratypes are less elongated, have 4–8 root lobes and are from more lateral rows. The crown is smooth and has a distinctly convex occlusal surface. Eorhinoptera is only the second genus of cow-nosed ray. Its distinctive crown morphology may have allowed it to exploit different kinds of prey than those favoured by rays that lacked convex tooth crowns.  相似文献   

7.
A new Category 1 species of Acanthobothrium van Beneden, 1850 is described from the cowtail stingray Pastinachus atrus (Macleay) collected from the Gulf of Carpentaria near Weipa, Queensland, Australia. This species is unique among Acanthobothrium Category 1 species in that it retains gravid proglottids on its strobila. It differs further from the 34 other Category 1 species in total length, proglottid number and testis number. The host identities of other Acanthobothrium species reported from Pastinachus are revised based on recent taxonomic work on rays of this genus. Given the revised host taxonomy, according to which P. atrus is the only member of its genus occurring off Australia, this should be considered to be the fifth species of Acanthobothrium reported from this Australian endemic species.  相似文献   

8.
The genus Anicetus includes economically important biocontrol agents that are introduced for control of soft and wax scale insect agricultural pests (Ceroplastes spp.). Understanding of host–parasitoid associations is critical to the successful outcome of their utilization in biological control projects. However, identification of these parasitoids is often difficult because of their small size and generally similar morphological features, and hence, studies on the host–parasitoid associations. Here, nucleotide sequence data were generated from the mitochondrial COI gene and the D2 region of 28S rRNA to assess genetic variation within and between species of Anicetus occurring in China. The results of this study support the use of the COI and the D2 region of 28S rRNA gene as useful markers in separating species of Anicetus, even in cases where morphological differences are subtle. On the other hand, the COI gene is also useful in recognizing species with much variation in morphology. DNA barcoding reveals high levels of host specificity of endoparasitoids wasps in the genus Anicetus. Our results indicate that each Anicetus species is adapted to a limited set of host species, or even are monospecific in their host choice.  相似文献   

9.
Empruthotrema chisholmae n. sp. is described from specimens recovered from a bull ray Pteromylaeus bovinus (Geoffroy Saint-Hilaire, 1817) at the Oceanogràfic Aquarium in Valencia, Spain. The bull ray was caught in the Spanish Mediterranean (Puerto de Mazarrón, Murcia). The new species resembles 4 others of the same genus ( Empruthotrema dasyatidis Whittington and Kearn, 1992, Empruthotrema kearni Whittington, 1990, Empruthotrema stenophallus Chisholm and Whittington, 2005, and Empruthotrema tasmaniensis Chisholm and Whittington, 1999) in having a haptor with 13 marginal loculi, the posteriormost loculus single and medial. The new species can be distinguished from these other species of the genus by the morphology of the sclerotized male copulatory organ, which is the shortest described. The new species also differs from the other species by the following combination of features: haptor with 13 marginal loculi, the presence of eyespots, the absence of an accessory piece associated with the male copulatory organ, and a long egg appendage (more than 150 μm). Empruthotrema chisholmae is the first species of the genus reported from the Mediterranean.  相似文献   

10.
Documenting patterns of host specificity in parasites relies on the adequate definition of parasite species. In many cases, parasites have simplified morphology, making species delimitation based on traditional morphological characters difficult. Molecular data can help in assessing whether widespread parasites harbour cryptic species and, alternatively, in guiding further taxonomic revision in cases in which there is morphological variation. The duck louse genus Anaticola (Phthiraptera: Philopteridae), based on current taxonomy, contains both host‐specific and widespread species. Mitochondrial and nuclear DNA sequences of samples from this genus were used to document patterns of host specificity. The comparison of these patterns with morphological variations in Anaticola revealed a general correspondence between the groups identified by DNA sequences and morphology, respectively. These results suggest that a more thorough taxonomic review of this genus is needed. In general, the groups identified on the basis of molecular data were associated with particular groups of waterfowl (e.g. dabbling ducks, sea ducks, geese) or specific biogeographic regions (e.g. North America, South America, Australia, Eurasia).  相似文献   

11.
The genus Chaenopsis presently includes 10 species, four in the eastern Pacific and six in the western Atlantic. Five individuals of an undescribed species of this genus were obtained at Gorgona Island in the eastern Pacific of Colombia, in depths between 3 and 5 m. This new species differs from all the Eastern Pacific species in an array of traits including meristic, coloration and morphometric characters. Chaenopsis celeste new species differs from its only sympatric species, C. deltarrhis, in having fewer pectoral rays, fewer dorsal spines and more dorsal-fin soft rays and anal-fin elements. This new species is found over shallow sandy, rubble and small rocks bottoms from Costa Rica to Colombia.  相似文献   

12.
A new Halosarpheia species, collected from driftwood from Hakkeijima beach, Yokohama, Japan, is described and illustrated and is compared with other species of the genus. The new fungus was growing together with its anamorph on a piece of decaying wood. SSU and LSU rDNA sequences for both morphs were 99% similar. Phylogenetic analyses of SSU and LSU rDNA sequences of the both morphs confirm their anamorph–teleomorph relationship and placed the new fungus in the Halosarpheia sensu stricto clade with high statistical support. Halosarpheia japonica is characterized by its polar appendage that is initially enclosed in a cellular sheath and dissolves in water, the appendage then swells to form a huge tree-like structure. The other three species currently included in Halosarpheia sensu stricto differ from H. japonica by having two polar appendages that uncoil in water to form long filaments.  相似文献   

13.
A new species of Manihot was discovered in the course of revising the taxonomy of some species of the genus occurring in the Midwest Region of Brazil. Its morphology resembles species which belong to different sections of the genus. However, a set of characters related to stem, leaves, inflorescences and flowers serves to differentiate it from the closest species, especially from M. falcata, to which it is most similar. The geographical distribution and conservation status of the new species as well as its flowering and fruiting period are also provided. Additionally, anatomical information about the aerial parts of the stem, a novelty regarding the wild species of the genus, is provided.  相似文献   

14.
In the African and Asian tropics, termites of the subfamily Macrotermitinae play a major role in the decomposition of dead plant material. Their ecological success lies in the obligate mutualism of the termites with fungi of the genus Termitomyces. Before the advent of molecular studies, the interaction with these fungi was poorly understood. Here, we combined available ITS sequence data from West, Central, and South Africa with data of 39 new samples from East Africa to achieve the most comprehensive view of the diversity and host specificity of Termitomyces symbionts across Africa to date. A high amount of sequence divergence in the ITS sequences was found; 11 different Termitomyces lineages in East Africa and >30 lineages across Africa were identified, and the expected diversity is estimated to be about 41 lineages. The fungal lineages belong to four major clades, each almost exclusively associated with one termite host genus. Analysis of molecular variance revealed that 40% of the ITS sequence variation occurred between host genera, indicating close co-evolution at this level. However, within host genera, fungal lineages and haplotypes were frequently shared among host species and sampling localities, except for fungal symbionts of Odontotermes. Horizontal transmission of fungal symbionts may facilitate the transfer of haplotypes and species among hosts. However, at present, we have little understanding of the maintenance of specificity at the genus level. Possible explanations range from substrate specificity of fungi to an active selection of fungi by termites.  相似文献   

15.
Two new tetraphyllidean species, Duplicibothrium cairae n. sp. and D. paulum n. sp., are described from Pacific cownose rays Rhinoptera steindachneri collected from the Gulf of California. D. cairae n. sp. differs from the only other known species in this genus, D. minutum, in its possession of two posteriorly bifurcating longitudinal septa on each bothridium and having a greater number of loculi per bothridium, wider bothridia and a greater number of segments per worm. D. paulum n. sp. differs from the above two species in being shorter, having two continuous longitudinal septa on each bothridium, rather than posteriorly bifurcating or absent longitudinal septa, having a greater number of loculi per bothridium and having fewer segments per worm. The generic diagnosis of Duplicibothrium is amended to reflect the inclusion of the two new species. Species of Duplicibothriumappear to be restricted to host species of the genus Rhinoptera. Systematic information gained from the study of these two new species supports the monophyly of the tetraphyllidean family Serendipidae and suggests that Duplicibothrium shares a phylogenetic heritage with species in the genera Glyphobothrium and Serendip, taxa that are also parasitic in cownose rays. Evidence for a phylogenetic relationship between serendipid species and species of Dioecotaenia is discussed, as are potential molluscan hosts for cestode species in Duplicibothrium and Dioecotaenia.  相似文献   

16.
Psoroptes mites are obligate ectoparasites of mammals that cause psoroptic mange in a number of domestic and wildlife species world-wide. Correct identification of species in this genus is important for eradication and quarantine programs. However, conflicting reports about species identity and host specificity within this morphologically conservative genus have raised questions regarding the usefulness of the taxonomic characters previously used to distinguish species. Records that rely only on host species do not provide accurate identification ofPsoroptes mites at the species level. This paper reviews the information available on life history, geographic distribution, and host specificity for this genus, with special reference to problems associated with identifying species in Australia.  相似文献   

17.
18.
The small genus Dialipsis Förster 1869 (Hymenoptera: Ichneumonidae) includes two known species, of which one is common in Central and Northern Europe. Here we describe the male and female of a new species, Dialipsis villahermosae Humala & Selfa, which was reared from mushrooms collected in Eastern Spain. The host fungus gnat, Mycetophila blanda Winnertz, is a new record for the whole genus, while the rate of parasitism seems very low. Based on environmental data of the collection localities and data available for other two species it is suggested that Dialipsis species occur preferably in cool temperatures habitats. A key of identification of the two known Palaearctic species is provided. D. villahermosae n. sp. differs from D. exilis Förster 1871 in the morphology of the first tergite, referred to the presence of dorsal keels and angle between petiole and postpetiole, and in the convexity of temples.  相似文献   

19.
The morphology of three remarkable genera of coccolithophores, Ophiaster, Michaelsarsia, and Calciopappus, is reviewed based on new images using field emission scanning electron microscopy. Each of these genera characteristically forms coccospheres with long appendages formed of highly modified coccoliths, which radiate from either the circum‐flagellar pole of the coccosphere (Calciopappus and Michaelsarsia) or the antapical pole (Ophiaster). For each genus, it is shown that the appendage coccoliths can also occur in an alternative orientation appressed to the main coccosphere. It is hypothesized that the appendage coccoliths are initially deployed in the appressed orientation and that extension of the appendages is a dynamic response to environmental stress. The observations suggest that coccoliths are more sophisticatedly adapted to specific functions than has been assumed and that the cytoskeleton plays more active roles in coccolith morphogenesis and deployment than has previously been inferred.  相似文献   

20.
The genus Liriomyza Mik (Diptera: Agromyzidae) is a diverse and globally distributed group of acalyptrate flies. Phylogenetic relationships among Liriomyza species have remained incompletely investigated and have never been fully addressed using molecular data. Here, we reconstruct the phylogeny of the genus Liriomyza using various phylogenetic methods (maximum likelihood, Bayesian inference, and gene tree coalescence) on target-capture-based phylogenomic datasets (nucleotides and amino acids) obtained from anchored hybrid enrichment (AHE). We have recovered tree topologies that are nearly congruent across all data types and methods, and individual clade support is strong across all phylogenetic analyses. Moreover, defined morphological species groups and clades are well-supported in our best estimates of the molecular phylogeny. Liriomyza violivora (Spencer) is a sister group to all remaining sampled Liriomyza species, and the well-known polyphagous vegetable pests [L. huidobrensis (Blanchard), L. langei Frick, L. bryoniae. (Kaltenbach), L. trifolii (Burgess), L. sativae Blanchard, and L. brassicae (Riley)]. belong to multiple clades that are not particularly closely related on the trees. Often, closely related Liriomyza species feed on distantly related host plants. We reject the hypothesis that cophylogenetic processes between Liriomyza species and their host plants drive diversification in this genus. Instead, Liriomyza exhibits a widespread pattern of major host shifts across plant taxa. Our new phylogenetic estimate for Liriomyza species provides considerable new information on the evolution of host-use patterns in this genus. In addition, it provides a framework for further study of the morphology, ecology, and diversification of these important flies.  相似文献   

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