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1.
Brachycaudus divaricatae (Hemiptera: Aphididae), a recent invader to Europe, has already reached Czech Republic. Partial sequences of mitochondrial COI and nuclear EF-1α genes have been analysed across the sixteen Czech samples of B. divaricatae, together with morphometric analysis of the same samples based on eighteen morphological characters of the apterous viviparous females. For comparative studies, thirteen samples from the Eastern Baltic region of Europe (Latvia, Lithuania and Poland) were used. All sampled populations appeared similar in their genetic and morphological characters studied. One haplotype of mitochondrial COI gene was predominant; it was characteristic for all samples from Czech Republic and 8 out of 13 samples from Eastern Baltic region. Two other haplotypes were found in the Eastern Baltic region only. Four different haplotypes of EF-1α gene were detected. Most of the samples (except one sample from the Eastern Baltic region and two samples from Czech Republic) had the same haplotype. Out of remaining three haplotypes, one was unique for the Eastern Baltic region, whilst two were found in Czech Republic only. For the present, Moravia is the southernmost region in Europe, where B. divaricatae has been already reported. Presumably, this invasive aphid species has entered the Czech Republic from the north via the Moravian Gate, a natural pass formed by the depression between the Western Carpathians and Eastern Sudetes.  相似文献   

2.
This study investigated the effects of a strain of the fungus Lecanicillium lecanii (Zimm.) Zare and Gams (Hypocreales: Ascomycota) on the aphid Schizaphis graminum (Rondani) (Hemiptera: Aphididae). The fungus was administered to fourth instar nymphs and to alate and apterous adult morphs as a ground rice-kernel formulation. This study showed that L. lecanii formulation affected the survival of the aphids and interacted differently with the studied morphs, the Lethal Time values being lower for alate compared to apterous morphs and nymphs. The treatment also caused a significant reduction in the fecundity of the three treated aphid groups. Histological analysis revealed that the hyphae invaded the host hemocoel of a limited number of alate and apterous morphs: the fungus only entered through the spiracles. Scanning Electron Microscope observations revealed that L. lecanii adhered to the body surface of both adults and nymphs without differentiation. In conclusion, the present study suggests that this strain might be a good candidate for a programme of biological control of S. graminum and other aphid species.  相似文献   

3.
Johnius (Johnius) majan sp. nov. is described on the basis of 8 specimens (117–158 mm in standard length) from Oman, Indian Ocean. The new species is distinguished from its congeners by the following combination of characters: black axillary spot on upper pectoral fin base; dorsal soft rays 29–32; anal soft rays 8; scales above lateral line 6, below 11; eye diameter 22.9–28.9% HL; interorbital width 32.0–38.0% HL; gill rakers 5–6 + 15–18 = 21–24; no mental barbel; last well developed pleural rib on 7th vertebra; swim bladder appendages 11; vertebrae 10 + 14 = 24.  相似文献   

4.
One new species each is proposed in Chalybea and Huilaea (Melastomataceae: Blakeeae). Chalybea peruviana has elliptic, 5-plinerved leaves with entire, revolute margins, inflorescences with 33–39 flowers, and is endemic to Peru. Huilaea calyptrata has inflorescences with 15–17, irregularly calyptrate flowers, anthers with a warty connective in the shape of an inverted hand fan, and is endemic to Ecuador. A key to the eight species of Huilaea is provided.  相似文献   

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Paraliparis adustus sp. nov., a snailfish species from the Bering Sea near the Aleutian Island Archipelago, Alaska, is described based on a single mesopelagic specimen. This new species is clearly distinguished by a combination of several morphological features and meristic counts, including long pointed gill rakers with 0–3 spinules at or near the tip, anus positioned forward near the pectoral symphysis, and color uniform brown. Paraliparis bullacephalus sp. nov. from Shelikof Strait, Gulf of Alaska, is also described. This new species is very similar in meristic characters and general body shape and size to P. holomelas Gilbert, but differs primarily in morphological features of the head, particularly in the shape of the dorsal contour of the head, snout, and opercular flap, mouth size, and eye position.  相似文献   

7.
Five isolates of a species of Colletotrichum were collected from Japanese barnyard millet (Echinochloa utilis) in Japan. Although the fungus had once been identi-fied as C. graminicola sensu lato, it was clearly different from C. graminicola isolated from maize (Zea mays) in its falcate and short conidia, 18.0–22.2 μm in length, cultural characteristics, and specific pathogenicity to E. utilis. Moreover, molecular phylogenetic analyses using sequences of rDNA-ITS, HMG, and SOD2 indicated a monophyly of the isolates. A new species, Colletotrichum echinochloae, is then proposed based on the morphological, pathological, and molecular characteristics.  相似文献   

8.
The bathyal genus Penopus (Ophidiidae) is revised based on 23 specimens. One specimen from the Ryukyu Trench represents a new species, Penopus japonicus. The remaining 22 specimens were found on both sides of the Atlantic Ocean, and neither 28 meristic and morphometric characters nor several morphological characters show any differences between the two populations. This supports Séret (1988), who considered Penopus macdonaldi Goode and Bean 1896 a junior synonym of Penopus microphthalmus (Vaillant 1888). The new Japanese species can be separated from the Atlantic species by having fewer rays in the dorsal (117 vs. 135–158) and anal (89 vs. 106–122) fins, the squamation of the head restricted to the middle part of the preopercle versus the squamation covering the dorsum, preopercle and the opercle in part, a distinct spine behind the posterior nostril versus the spine hardly visible and 9 spines on the hind margin of the preopercle versus 4–7 spines.  相似文献   

9.
Sexual reproduction of Rhopaloeides odorabile, a common Great Barrier Reef sponge, was quantified using histological sections from samples collected over two reproductive seasons. Rhopaloeides odorabile is viviparous and gonochoristic with a male biased sex ratio (2.5:1). Commencement and cessation of gametogenesis coincides with rising and falling sea surface temperatures (≈24–29°C). Spermatogenesis occurs from October until January. Females initiate oogenesis in September with the asynchronous development of oocytes, embryos and larvae occurring within the brood chambers. A larval release period of 5–6 weeks occurs during January and February. The minimum size of reproductive individuals was 176 cm3 for females and 192 cm3 for males. The total reproductive output for both sexes shows a positive correlation with size. A relative reproductive output index quantified the maximum reproductive investment at approximately 1 and 3% of the total choanoderm for females and males, respectively, which represents a lower range of reproduction in comparison to other viviparous sponges. Low reproductive output in R. odorabile may be offset by an extended spawning period, alleviating the risk of releasing larvae in potentially adverse conditions via one synchronised spawning event and increasing overall larval survival.  相似文献   

10.
Echinorhynchus hexagrammi Baeva, 1965 is redescribed on the basis of specimens collected from the saffron cod Eleginus gracilis (Tilesius) in Akkeshi Bay (western North Pacific) off Hokkaido, Japan. Eighteen museum specimens deposited as E. salmonis Müller, 1784 from Japanese coastal waters were also re-examined and re-identified as E. hexagrammi. Hexagrammos stelleri Tilesius, Hemitripterus villosus (Pallas), Podothecus sachi (Jordan & Snyder), Sebastes oblongus Günther and Verasper moseri Jordan & Gilbert are recognised as new hosts for E. hexagrammi. This acanthocephalan can be distinguished from three morphologically similar species, E. gadi Zoega in Müller, 1776, E. laurentianus Ronald, 1957 and E. salmonis, by the possession of the following characters: 12–16 (usually 14) rows of hook on the proboscis, a proboscis width of 170–240 μm in males and 195–270 μm in females, a hook root length of 35–45 μm in males and 40–50 μm in females, and linearly or almost linearly arranged cement glands in males.  相似文献   

11.
Three new species of the Brazilian genus Luetzelburgia Harms (Leguminosae, Papilionoideae, Sophoreae sensu lato (Vataireoid clade)) are described and illustrated under the names Luetzelburgia harleyi D. Cardoso, L. P. Queiroz &; H. C. Lima, L. neurocarpa D. Cardoso, L. P. Queiroz &; H. C. Lima and L. purpurea D. Cardoso, L. P. Queiroz &; H. C. Lima. All three occur in the caatinga vegetation of the State of Bahia, Eastern Brazil. A discussion of the morphological characters distinguishing the new species from their close relatives, as well as an identification key to all known species of Luetzelburgia, are presented.  相似文献   

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14.
Summary   Linaria khalkhalensis Hamdi & Assadi is described as a new species from Azerbaijan and Guilan provinces (northern Iran), belonging to Linaria sect. Linaria. It is close to Linaria lineolata Boiss. and L. elymaitica (Boiss.) Kuprian., which it resembles in habit and vegetative features. However, floral and seed characters together with a distinctive geographical distribution, warrant recognition at the species rank. An illustration of the new species, a distribution map, scanning electron micrographs of seed and capsule surfaces, and an identification key are also included.  相似文献   

15.
Apterous viviparous females of Neoamphorophora ledi (Wahlgren, 1938) living on Rhododendron degronianum Carr. (Ericaceae) on Honshu island, Japan, are redescribed and the hitherto unknown alate viviparous females are here described. Rhododendron degronianum is a new host plant species for this aphid. This species is recorded for aphid fauna of Eastern Palearctic for the first time. Keys to species of Neoamphorophora based on apterous and alate viviparous females are given. A key to aphid genera with swollen siphunculi living on species of Rhododendron worldwide based on apterous viviparous females is also provided.  相似文献   

16.
Five new species, Petrobius caucasicus sp. n., Trigoniophthalmus presimplex sp. n., T. divnogorski sp. n., T. kislovodski sp. n., and T. adigei sp. n. (Machilidae), are described from the Caucasus. A key to all the known species of the genus Trigoniophthalmus is given. Two subgenera (Trigoniophthalmus s. str., Trigoniocellus subgen. n.) in the genus Trigoniophthalmus are described. 2 + 2 retractile vesicles are present on abdominal segments II–IV in the species of Trigoniocellus subgen. n. and on II–V abdominal segments in Trigoniophthalmus s. str. Analysis of the evolution and phylogenetic relations between the species of the genus Trigoniophthalmus is performed for the first time. The formation of bristletails of the genus Trigoniophthalmus appears to occur in the Caucasian mountain province of the European area, from where they penetrated to the Central European mixed province and the Mediterranean subarea. Among the described species of the genus, T. kislovodski is distinguished by the greatest number of plesiomorphic states of morphological characters.  相似文献   

17.
Nitraria retusa and Atriplex halimus (xero-halophytes) plants were grown in the range 0–800 mM NaCl while Medicago arborea (glycophyte) in 0–300 mM NaCl. Plants were harvested after 120 days of salt-treatment. The present study was designed to study the effect of salinity on root, stem and leaf anatomy, water relationship, and plant growth in greenhouse conditions. Salinity induced anatomical changes in the roots, stems and leaves. The cuticle and epidermis of N. retusa and A. halimus stems were unaffected by salinity. However, root anatomical parameters (root cross section area, cortex thickness and stele to root area ratio), and stem anatomical parameters (stem cross section area and cortex area) were promoted at 100–200 mM NaCl. Indicating that low to moderate salinity had a stimulating effect on root and stem growth of these xero-halophytic species. At higher salinities, root and stem structures were altered significantly, and their percentages of reduction were higher in A. halimus than in N. retusa whereas, in M. arborea, they were strongly altered as salinity rose. NaCl (100–300 mM) reduced leaf water content by 21.2–56.2% and specific leaf area by 51–88.1%, while increased leaf anatomical parameters in M. arborea (e.g. increased thickness of upper and lower epidermis, palisade and spongy mesophyll, entire lamina, and increased palisade to spongy mesophyll ratio). Similar results were evidenced in A. halimus leaves with salinity exceeding 100 mM NaCl. Leaves of N. retusa were thinner in salt-stressed plants while epidermis thickness and water content was unaffected by salinity. The size of xylem vessel was unchanged under salinity in the leaf’s main vein of the three species while we have increased number in M. arborea leaf main vein in the range of 200–300 mM NaCl. A longer distance between leaf vascular bundle, a reduced size and increased number of xylem vessel especially in stem than in root vascular system was evidenced in M. arborea treated plants and only at (400–800 mM) in the xero-halophytic species. The effects of NaCl toxicity on leaf, stem and root ultrastructure are discussed in relation to the degree of salt resistance of these three species. Our results suggest that both N. retusa and A. halimus show high tolerance to salinity while M. arborea was considered as a salt tolerant species.  相似文献   

18.
Chaetomium is a fungus species that inhabits different cellulose substrates. Some species of this genus destroy books, textile, and wood. This genus is of particular interest due to its antagonistic and enzyme peculiarities. Studies on morphological and cultural features of Chaetomium species have both theoretical and practical output. Growth rates and development of C. globosum, C. funicola, C. elatum, and C. spirale were studied under different temperatures (17–20°C, 25°C, 27°C, 30°C, and 33–35°C) and carbon source media (glucose, saccharose, mannite, lactose, amylum, and cellulose). The optimal growth temperature was 25–27°C for all the studied species, while the temperature range of 33–35°C inhibited the colonies’ growth. Growth dynamics and colony shape and morphology, as well as development of overhead mycelium and ascocarps, varied greatly in different Chaetomium species in regard to the carbon source media. When comparing the destructive effect of four studied species and C. murorum on craft paper, the highest activity was registered for C. globosum, C. funicola, and C. elatum.  相似文献   

19.
A new Dactylella species, Dactylella alba was isolated from the ascospores of Orbilia alba collected in Wenshan County, Yunnan Province, China. Conidiophores were either not branched or occasionally branched, bearing divergent sterigmata on the tip with single conidium on each. Conidia were elongated ellipsoids, 1–2 septate, mostly 1 septate. By combining the ITS sequence with morphological characteristics, a new anamorphic species is described and illustrated together with its teleomorph.  相似文献   

20.
This is the report of a new species of catfish, Kryptoglanis shajii nov. gen. and nov. sp., distinguished from all other genera of siluriform fishes by the combination of the following morphological characters: viz. the absence of dorsal fin; the presence of four pairs of barbels; an upwardly directed mouth, with a distinctly projecting lower jaw; subcutaneous eyes; anal fin completely confluent with the caudal fin; anal and caudal fins together carry 70–74 fin rays; and no spines in any of the fins. Kryptoglanis, which has a maximum recorded size of 59.1 mm in standard length, was collected from a well fed by subterranean springs. The type locality is a well located at the extreme western part of Western Ghats, near Chalakudy in Thrissur district, Kerala State, India.  相似文献   

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